körforgásos gazdaság és környezetvédelemsolution on sacrificial polyurethane and zeolite foam...

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Volume 1, Issue 2, 2017

VVolume 3, Issue 1, 2019

Körforgásos Gazdaság és

Környezetvédelem

Circular Economy and Environmental Protection, vol. 3, issue 1 (2019)

Körforgásos Gazdaság és Környezetvédelem, 3. évfolyam, 1. szám (2019)

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EDITORIAL INFORMATION

Editor-in-Chief: Mizsey, Peter

Editorial Advisory Board:

Kraslawski, Andrzej

Mika, Laszlo Tamas

Nagy, Tibor

Plesu, Valentin

Reti, Gabor

Stawski, Dawid

Szlavik, Janos

Toth, Andras Jozsef

Valentinyi, Nora

Vatai, Gyula

Viskolcz, Bela

Journal Editor: Racz, Laszlo (sr)

Assistant Editors:

Andre, Anita

Farkas Szoke-Kiss, Anita

Fozer, Daniel

Haaz, Eniko

Publishers:

Environmental and Process Engineering Research Group, and Institute

of Chemistry – Mizsey, Peter

ISSN 2560-1024

Contact, manuscript submission: [email protected]

On the first page: An illustration of water cleaning using bacterial

cellulose-based hybrid membranes (by courtesy of El Mrabate, Bilal)



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CONTENTS / TARTALOM

Editorial preface / Szerkesztői előszó………………………………………………………..4

Udayakumar, Mahitha – El Mrabate, Bilal – Koós, Tamás – Szemmelveisz, Katalin –

Lakatos, János – Vanyorek, László – Németh, Zoltán: Preparation and investigation

of carbon foams from waste

polyurethanes………………….……….………………..……………………….pp. 5–15.

El Mrabate, Bilal – Udayakumar, Mahitha – Schabikowski, Mateusz – Németh, Zoltán:

Comparative Electron Microscopy study of the ZnO/MWCNT nanocomposites

prepared by different methods

………………………………………………………..………………………..…pp. 16–24.

Tóth, András József: Összefoglaló az ÚNKP 18-4-BME-209 kódszámú pályázat

kutatásairól (2018/2019/2) ……..……………………………………………….pp. 25–29.

Tóth, András József: Beszámoló a 29th European Symposium on Computer Aided

Process Engineering (ESCAPE29) rendezvényről (Eindhoven, 2019. június 16–19.)

…………….…………………………………………………………………...….pp. 30–31.

Környezetorientált Szén-dioxid Partnerség (ECO2P) a Miskolci Egyetemen…pp. 32–33.

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4

EDITORIAL PREFACE /

SZERKESZTÖI ELŐSZÓ

Tisztelt / Kedves Olvasó,

Harmadik évfolyamunkat kezdjük meg

ezzel a számmal, melyben a tudományos

közlemények kiadványunk másik

kutatócsoportjából származnak,

nevezetesen a Miskolci Egyetem Kémiai

Intézete (https://ki.uni-miskolc.hu/) egyik

csoportjának kutatómunkájáról számolnak

be.

Az első közlemény a hulladék puliuretán

habok ésszerű és a körforgásos gazdaság

alapeveinek szellemében kidolgozott

hasznosítási megoldásáról számol be.

A második közlemény a cink-oxid

bevonatú szén nanocsövek különböző

előállítási megoldásairól és azok

összehasonlításáról szól. A téma első

pillanatra távolinak tűnik a kiadványunk

küldetésében megfogalmazott elvektől, de

a kutatás eredményeivel hozzájárul

ezeknek a viszonylag új, sokszor

hulladékból is előállítható anyagok

vielkedésének és környezetorientált

használhatóságának megismeréséhez.

Bemutatjuk az Új Nemzeti Kíválóság

Program keretében elért kutatási

eredményeket.

Fontos híreket is megosztunk olvasóinkkal.

Beszámolunk a Miskolci Egyetem Kémiai

Intézetében 2019 áprilisában tartott

jubileumi, ünnepi ülésről, illetve a

„European Symposium on Computer

Aided Process Engineering” Eindhovenben

tartott idei konferneciájáról.

Budapest, Miskolc, 2019. június 30.

Mizsey Péter

https://ki.uni-miskolc.hu/

Udayakumar, Mahitha – El Mrabate, Bilal – Koós, Tamás – Szemmelveisz, Katalin – Lakatos, János

– Vanyorek, László – Németh, Zoltán: Preparation and investigation of carbon foams from waste

polyurethanes

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Preparation and investigation of carbon foams from waste

polyurethanes

Udayakumar, Mahitha1,2

, El Mrabate, Bilal2, Koós, Tamás

3, Szemmelveisz,

Katalin3, Lakatos, János

2, Vanyorek, László

1,2, Németh, Zoltán

1,2*

1Higher Education and Industry Cooperation Center of Advanced Materials and

Intelligent Technologies, University of Miskolc, Miskolc-Egyetemváros, H-

3515, Hungary 2Institute of Chemistry, University of Miskolc, Miskolc-Egyetemváros, H-3515,

Hungary 3Department of Combustion Technology and Thermal Energy, University of

Miskolc, Miskolc-Egyetemváros, H-3515, Hungary Corresponding author. Tel.:+36 46 565 111/1380. E-mail: [email protected] (Németh, Zoltán)

Received: 6 June, 2019 Accepted: 20 June, 2019

ABSTRACT

Nowadays, the recycling of

polyurethane wastes is gaining much

importance owing to its increased

commercial market. An attempt was

made to produce carbon foams by

utilising the waste polyurethane

elastomers and semi-flexible foams as

template and impregnating them in

sucrose precursor solution followed by

carbonisation at different temperatures

(300–900 °C) in N2 atmosphere. The

BET (based on Brunauer, S., Emmett,

P.H. and Teller, E. gas absorption

concept) surface area of carbon foams

produced from two different

polyurethane foams are found to be 370

m2/g and 217 m

2/g at 900 °C,

respectively. In both cases, the carbon

content of about 92–95% was achieved

for samples pyrolysed at 900 °C. The

obtained carbon foams showed the

characteristic type I adsorption

isotherm, which represents the typical

microporous material. The surface

morphology and the chemical

composition of the carbon foams were

investigated with Scanning Electron

Microscopy (SEM) and Energy

Dispersive X-ray Spectroscopy (EDS).

INTRODUCTION

Plastic waste management is one of the

major challenging areas because of the

manifold usage of plastic products and

inadequate techniques on their recycling.

At present, the most inevitable and thriving

polymer material in use is the

polyurethanes (PUs) with the annual

worldwide production of about 18 million

tonnes. The largest sectors of

polyurethanes are flexible foams, rigid

foams, coatings and elastomers. The waste

polyurethane foam usually undergoes open

burning, incineration or landfilling.

Combustion in open atmosphere and

landfilling of polyurethanes has many

serious environmental impacts. Moreover,

in some European countries, the disposal

of plastic wastes in landfills has been

decreasing over the last decade, through

recycling and energy recovery (Milios, L.,

mailto:[email protected]



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Davani. A.E, & Yu, Y. (2018)).

Polyurethane foam (PUF) wastes can be

recycled in many ways, through

mechanical crushing and rebonding (Datta,

J., & Chojnacka, M. (2011)), chemical

methods like hydrolysis (Gerlock, J.L. et

al. (1980)), glycolysis (Datta, J., &

Haponiuk, J.T. (2011)), aminolysis

(Chuayjuljit, S., Norakankorn, C., &

Pimpan, V. (2002)) and via

thermochemical methods which includes

pyrolysis (Garrido, M.A., Font, R., &

Conesa, J.A. (2016)), gasification (Guo,

X., et al (2015)) or hydrogenation. Many

studies have investigated the thermal

decomposition and the pollutant emission

of polyurethane foams in an inert and

oxygen atmosphere (Garrido, M.A, &

Font, R. (2015); Garrido, M.A, Font, R., &

Conesa, J.A. (2016)). An efficient

technique to recycle the polyurethane foam

wastes is essential to reduce the

environmental burden and pollutant

emissions from open burning /combustion.

Carbon foam (CF) prepared using

polyurethane foam template is one of the

major research interests of the

contemporary world. Carbon foam is a

promising material for different

applications because of its several

appealing properties like lightweight,

chemical inertness, high thermal stability,

specific pore structure and surface

properties (Inagaki, M., Qiu, J., & Guo, Q.

(2015)). There are several methods for the

fabrication of carbon foams. One such

method uses blowing of carbon precursors

through pyrolysis under pressure or by

adding some chemical blowing agents like

pentane (Liu, M. et al. (2007)) [i],

aluminium nitrate (Narasimman, R.,

Vijayan, S., & Prabhakaran, K. (2014)),

boric acid (Narasimman, R., &

Prabhakaran, K. (2013)). Furthermore,

mesophase pitch (Mehta, R., Anderson,

D.P., & Hager, J.W. (2003)), novolac type

phenol formaldehyde resin (Lei, S. et al.

(2010)), poly(arylacetylene) (Prabhakaran,

K. et al. (2007)), polyacrylonitrile (Yang,

J. et al (2013)), were used as precursors for

synthesising carbon foam by applying

blowing agent. The simplest and the most

effective method for the fabrication of non-

graphitic carbon foams with controlled

pore structure and pore size distribution is

the template replica method, in which the

polymer foam templates are immersed into

carbon precursor solutions followed by

carbonisation at high temperature. A

honeycomb open cell structure of carbon

foam was obtained by impregnation of

polyurethane foam using different

precursors. Qian, X. et al. (Qian, X. et al

(2017)) produced carbon foams by

immersing the polyurethane foam into

phenolic resin solution followed by

polymerisation and carbonisation in N2

atmosphere at 900 ℃. Yadav, A. et al.

(Yadav, A. (2011)) used coal tar based

mesophase pitch and polyurethane foams

to synthesise carbon foams (at 1 000 ℃)

and graphite foams (at 1 400 ℃) in N2

atmosphere. Impregnation of polyurethane

foams in poly(amide acid) followed by

imidization and carbonisation at 1 000 ℃

in a flow of argon gas was reported by

Inagaki, M. et al. (Inagaki, M. (2004)).

Carbon foam was also prepared by direct

carbonisation (1050 ℃, argon atmosphere)

of melamine foam for 3h without any

structural modification (Yu, S. et al.

(2018)). On the other hand, Farhan, S. et

al. (Farhan, S. et al. (2016)) prepared a

lightweight carbon foam with fireproofing

and anti-ablation properties using waste

rigid polyurethane foam as template and

solid novolac or liquid resole as binder.

Synthesis of carbon foams from

polyurethane foams with 30 PPI (pores per

inch) was studied by Nam, G. et al. (Nam,

G. et al (2013)), using different precursors

resins and carbonised the impregnated

foams at 830 ℃ for 3h in argon

atmosphere. The preparation of carbon

foams in a greener way using sucrose as

carbon source is also gaining much

attention nowadays. Sucrose is a widely

available renewable raw material and



polyurethanes

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reported to be an efficient and excellent

source of carbon in many earlier

researches. Prabhakaran, K. et al.

(Prabhakaran, K. et al (2007)) synthesised

low density carbon foams using acidic

sucrose solution through sintering in the

temperature range of 600–1400 ℃ in

vacuum. Jana, P. et al. (Jana, P., Fierro, V.,

& Celzard, A. (2013)) disclosed the

synthesis of carbon foams using sucrose

carbon source and waste polyurethane

cleaning pad templates through

carbonisation at 900 ℃ for 1h in nitrogen

flow. In addition, the work of Saini, V.K.

et al. (Saini, V.K., Pinto, M.L., & Pires, J.

(2013)) described the synthesis of micro /

mesoporous carbon foams by acid

catalysed polymerisation of sucrose

solution on sacrificial polyurethane and

zeolite foam templates followed by

carbonisation at 875 ℃ under vacuum for

1h.

Therefore, the synthesis of carbon foam

using polyurethane foam template is a

possible way of recycling the wastes in an

effective manner. Apart from the earlier

studies, more investigation needs to be

done in order to understand the pyrolysis

of carbon enriched polyurethane foams. In

the past, various carbon precursors were

used for the synthesis of carbon foams

using template method. On the other hand,

the heat treatment temperature is also

essential, which determines the properties

of the carbon foam. In this work, we have

shown the behaviour of carbon foams at

different heat treatment conditions and

analysed their properties with various

characterisation techniques.

EXPERIMENTAL SECTION

Materials

Two different post-industrial waste

polyurethane foams were collected –

polyurethane elastomer (EF) from Elastico

Kft., Hungary and semi-flexible

graphitised foam (GF) from BorsodChem

Ltd., Hungary. Concentrated sulphuric acid

(cc. H2SO4, 96 wt%) was purchased from

VWR International Kft., Hungary and

ordinary table sugar (sucrose) from

supermarket.

Synthesis of carbon foams

In the present work, polyurethane

elastomers and semi-flexible foams were

used as sacrificial templates and acidified

sucrose solution as carbon precursor for

the synthesis of carbon foams. The

precursor solution was prepared by adding

200 ml of dilute sulphuric acid (2.8 wt%)

to 500 g of sucrose taken in a glass beaker

and heated the mixture to about 100 ℃

with continuous stirring until the sucrose

gets completely dissolved in the diluted

acid. The samples were then placed inside

the hot air oven at 110 ℃ for 10h for

cross-linking. Upon thermal

polymerisation, a stiff and black coloured

foam structure was obtained.

The carbonisation of the impregnated PU

foams was done using tube furnace

(Carbolite® 1 200 °C Split Tube

Furnace VST 12/900). The samples taken

in a quartz boat were placed inside the tube

furnace and carbonised at certain

temperature at a heating rate of 5°C/min

for 1 h in N2 atmosphere. Four different

temperatures such as 300 ℃, 500 ℃, 700

℃ and 900 ℃ were chosen to observe the

effect of heat treatment temperature on the

properties of carbon foam. As a result, a

porous structure of carbon with reduced

size and weight has been obtained. Before

taking out the samples, they must be

cooled inside the furnace in the stream of

nitrogen for 20 min.

CHARACTERISATION

To understand the thermal behaviour of the

impregnated PU foams, the thermal

decomposition was carried out in oxygen



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and nitrogen atmosphere at four different

temperatures in a SYLAB IF 2000G

heating microscope analyser. The surface

morphology of the carbon foams

synthesised at various conditions was

investigated by scanning electron

microscopy (SEM) and the measurement

was performed by a Hitachi S-4800 Type

II FE-SEM instrument operating in the

range of 0–30 keV. Prior to the

measurement, the samples were mounted

on a conductive carbon tape. The energy-

dispersive X-ray spectroscopy (EDS)

measurement was completed with the

scanning electron microscope and a Röntec

XFlash Detector 3001 SDD device. In

addition, the percentage of carbon and

other trace elements present in the carbon

foams were measured by Carlo Erba

EA1108 CHNS-O analyser. Nitrogen (N2)

adsorption-desorption experiments were

carried out at 77 K to determine the

Brunauer-Emmett-Teller (BET) (Brunauer,

S., Emmett, P.H. & Teller, E. (1938))

surface area and micropore volume (t-plot

method) using ASAP–Accelerated Surface

Area and Porosimetry System 2020

(Micromeritics Instrument Corp.,

Germany). Prior to each measurement, the

samples were degassed by passing the

nitrogen gas along with heating at 90 °C

for 24h.

RESULTS AND DISCUSSION

Heating microscope analysis

After thermal polymerisation of the

impregnated PU foams, their behaviour

when subjected to different heat treatment

temperatures in oxygen and nitrogen

atmosphere was measured using heating

microscope analyser. The images of carbon

foams with different heat treatment

temperatures are shown in Figure 1.

Fig. 1. Heating microscope image of carbon foams pyrolysed at different conditions

(RT–room temperature; EF–polyurethane elastomer; GF–semi-flexible graphitised foam)



polyurethanes

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From the image analysis, it can be evident

that the foams behave differently in the

two atmospheres. In both the foam types,

the increase in temperature in oxygen

environment destroys the foam structure

and during higher temperatures (700 ℃

and 900 ℃), only some traces of material

remains, whereas pyrolysis in nitrogen

atmosphere prevents complete oxidation of

the impregnated foams even at high

temperatures. As a result, the original

structure of the foams has been reproduced

with reduced size and weight.

SEM and EDAX

The surface morphology of carbon foams

prepared at four different temperatures was

measured using Scanning Electron

Microscopy (SEM) and chemical

composition by Energy Dispersive X-ray

Spectroscopy (EDS). Figure 2 shows the

SEM image of carbon foams synthesised

from semi-flexible PU foams (GF) at

different carbonisation temperature in N2 at

lower magnification.

Fig. 2. SEM micrograph of carbon foams prepared from GF at different temperatures

300 °C

700 °C

500 °C

900 °C



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From the micrograph (on Fig. 2), it can be

seen that the pore size and structure of the

carbon foams are not homogeneous and

some cleavage in the strut joint of the cells

could be observed. It is the same in all the

four different temperatures. This is because

the struts and cell walls of the semi-

flexible foams are brittle and collapsed on

squeezing during coating or impregnation

and further upon thermal treatment.

The carbon foam (CF) synthesised from

polyurethane elastomer (EF) at different

carbonisation temperature in N2 exhibit

different morphology than the other (see

Figures 3 and 4). Figure 3 represents the

closed porous structure of the carbon

foams at lower magnification. Hence, a

separate micrograph of carbon foams at

higher magnification at 500 ℃ and 900 ℃

has shown (Figure 4 on the next page). It

can be observed that the cell of the carbon

foams (900 ℃) are porous with an average

pore size of 0.2 μm and contains carbon

with microspheres.

Fig. 3. SEM micrograph of carbon foams prepared from EF at different temperatures

300 °C

700 °C 900 °C

500 °C



polyurethanes

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Fig. 4. SEM micrograph of carbon foams prepared from EF at 500 ℃ and 900 ℃

Fig. 5. EDS analysis prepared from EF (left) and GF (right) at 900 ℃

500 °C 500 °C

900 °C 900 °C



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On the other hand, the elemental

composition of the as-prepared carbon

foams synthesised from EF and GF at 900

℃ are shown in Figure 5 (on the previous

page). In the graph, the most intense peak

represents the carbon (C) content and the

smaller peaks indicate trace amount of

oxygen (O) and the residual sulphur (S).

Elemental analysis

Apart from EDS, the carbon content of the

foams was checked by measuring the

samples with CHNS-O analyser. The

results of the elemental analysis are given

in Table 1, which represents the percentage

of carbon present before and after

carbonisation at different temperatures.

Sample Polyurethane elastomer Semi-flexible graphitised foam

Raw foam 62.9 68.3

Impregnated

foam

55.1 51.3

300 oC 75.7 74.3

500 oC 88.5 82.7

700 oC 91.8 92.9

900 oC 92.4 94.9

Table 1. Carbon content (%) of carbon foams

It could be observed that the carbon

content is increasing at higher temperatures

reaching a maximum of about 92.4 % (EF)

and 94.9 % (GF), respectively.

Surface area measurement (BET)

The nitrogen adsorption-desorption test

was conducted to determine the specific

surface area, total pore volume and pore

size of the carbon foams (see Table 2).

Nitrogen sorption isotherm (see Figure) on

pyrolysed at higher temperature (700 °C

and 900 °C) shows the characteristic type I

adsorption isotherm, which are the typical

features of microporous material having

relatively small external surfaces and

narrow micropores. Carbon foam achieved

a maximum SBET of 370 m2/g (EF) at 900

℃. Increase in temperature increases the

SBET and total pore volume (0.21 cm3/g)

and reduces the pore size (2.2 nm) in case

of carbon foam synthesised from EF.

Sample BET surface

area (SBET),

m2/g

Micropore

area,

m2/g

External

surface area,

m2/g

Total pore

volume,

cm3/g

Pore size,

mm

EF500 69 47 22 0.06 3.5

EF700 311 266 45 0.18 2.4

EF900 370 338 32 0.21 2.2

GF500 128 91 37 0.08 2.5

GF700 265 237 28 0.14 2.1

GF900 217 200 17 0.11 2.1

Table 2. Surface area measurement and values



polyurethanes

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Fig. 6. Nitrogen sorption isotherm of carbon foam synthesised from EF at different

temperatures

CONCLUSIONS

This study reports on the preparation and

characterisation of carbon foams with the

objective of further improvement and using

them in many favourable applications.

Carbon foams were successfully

synthesised using waste polyurethane

elastomers and semi-flexible foams as

template and widely available raw material

sucrose as carbon source. The macro- and

micro-structures of carbon foams

synthesised in different conditions were

investigated. The maximum surface area of

370 m2/g with an increased pore volume of

0.21 cm3/g were achieved for carbon foams

prepared from EF at 900 ℃. Nitrogen

sorption isotherm represents the

characteristic type I adsorption isotherm,

which has shown that the produced carbon

foams contain extensive micropores. EDS

and elemental analysis confirmed the

higher carbon content (about 92–95 %) of

the foams synthesised at 900 °C.

ACKNOWLEDGEMENT

The described article was carried out as

part of the EFOP-3.6.1-16-2016-00011

‘Younger and Renewing University –

Innovative Knowledge City – institutional

development of the University of Miskolc

aiming at intelligent specialisation’ project

implemented in the framework of the

Szechenyi 2020 programme. The

realisation of this project is supported by

the European Union, co-financed by the

European Social Fund. Special thanks to

István Slezsák, Dr. and the Innovációs

Laboratórium Kft. (Hungary) to provide us

with SEM investigations. Co-authors U.M.

and N.Z. also acknowledge the support of

the European Union and the Hungarian



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14

Government in the framework of the

GINOP 2.3.4-15-2016-00004 ‘Advanced

materials and intelligent technologies to

promote the cooperation between the

higher education and industry’.

Keywords: polyurethane wastes, carbon

foams, pyrolysis, recycling, sucrose

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cell wall and strut for CO2 capture. RSC

Advances, 4(2), 578–582.

Prabhakaran, K., Singh, P.K,, Gokhale, N.M.,

& Sharma, S.C. (2007). Processing of

sucrose to low density carbon foams. Journal

of Material Science, 42(11), 3894–3900.

Qian, X., Ren, M,, Yue, D,, Zhu, Y., Han, Y.,

Bian, Z., & Zhao, Y. (2017). Mesoporous

TiO2 films coated on carbon foam based on



polyurethanes

__________________________________________________________________________________

__________________________________________________________________________________15

waste polyurethane for enhanced

photocatalytic oxidation of VOCs. Applied

Catalysis B: Environmental, 212, 1–6.

Saini, V.K., Pinto, M.L., & Pires, J. (2013).

Synthesis and adsorption properties of

micro/mesoporous carbon foams prepared

from foam-shaped sacrificial templates.

Materials Chemistry and Physics, 138(2-3),

877–885.

Yadav, A., Kumar, R., Bhatia, G., & Verma,

G.L. (2011). Development of mesophase

pitch derived high thermal conductivity

graphite foam using a template method.

Carbon, 49(11), 3622–3630.

Yang, J., Yang, G., Yu, D., Wang, X., Zhao,

B., Zhang, L., Du, P., & Zhang, X. (2013).

Carbon foams from polyacrylonitrile-borneol

films prepared using coaxial

electrohydrodynamic atomization. Carbon,

53, 231–236.

Yu, S., Chen, Z., Wang, Y., Luo, R., & Pan, Y.

(2018). A study of thermal insulation

properties and microstructure of ultra-light

3D-carbon foam via direct carbonization

of polymer foam. Journal of Porous

Materials, 25(2), 527–536.



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16

Comparative Electron Microscopy study of the ZnO/MWCNT

nanocomposites prepared by different methods

El Mrabate, Bilal1, Udayakumar, Mahitha

1,2, Schabikowski, Mateusz

3,

Németh, Zoltán1,2 *

1Institute of Chemistry, University of Miskolc, Miskolc-Egyetemváros, H-3515,

Hungary 2 Higher Education and Industry Cooperation Center of Advanced Materials and

Intelligent Technologies, University of Miskolc, Miskolc-Egyetemváros, H-

3515, Hungary 3Institute of Nuclear Physics, Polish Academy of Sciences, 31342 Krakow,

Poland Corresponding author. Tel.:+36 46 565 111/1380. E-mail: [email protected] (Németh, Zoltán)

Received: 06 June, 2019 Accepted: 20 June, 2019

ABSTRACT

Zinc oxide (ZnO) coated multi-walled

carbon nanotube (MWCNT) composites

with different morphology were

prepared successfully via impregnation

and solvothermal process using zinc

acetate (Zn(CH3COO)2 × 2H2O) as

precursor and ethanol (EtOH) as solvent.

As-prepared ZnO coated MWCNT

composites were characterised by

scanning electron microscopy (SEM),

energy dispersive X-Ray spectroscopy

(SEM-EDAX) and Raman microscopy

techniques. Observations revealed that

using different preparation methods the

formation of morphologies of ZnO

particles on the surface of MWCNTs can

be controlled.

INTRODUCTION

Carbon nanotubes (CNTs) both of single-

walled carbon nanotubes (SWCNTs) and

multi-walled carbon nanotubes

(MWCNTs) draw great attention since they

were discovered by Iijima in 1991 (Iijima,

S. (1991)). Due to their special features,

for example extremely high stability or

unique electronic and outstanding

mechanical properties (Saito, R.,

Dresselhaus, G., & Dresselhaus, M.S. (ed.-

s) (1998); Rao, C.N.R., Müller, A., &

Cheetham, A.K. (ed.-s) (2004)). CNTs are

promising candidates in many applications

such as composite materials (De Volder,

M.F.L. et al. (2013)), field emission

materials (Lim, S.C. et al. (2009)) or

chemical sensors (Aroutiounian, V.M. et

al. (2013)).

In the last two decades many studies and

reviews were published on the combination

of CNTs with metal oxide nanoparticles

(Chu. H. et al. (2010)). The applications of

these composites are very extensive, which

usually determines the performance of the

composites. One of the most interesting

field of CNT-based nanocomposites when

the surface of carbon nanotubes is covered

with inorganic metal oxide layer, which

layer may consist of separated

nanoparticles (Song, HJ. et al. (2012)) or

can be totally homogeneous (Németh, Z. et

al. (2011)). In this regard, there have been

several recent investigations concerning

mailto:[email protected]


Comparative Electron Microscopy study of the ZnO/MWCNT nanocomposites prepared by different

methods

__________________________________________________________________________________

__________________________________________________________________________________17

the attachment of ZnO onto MWCNTs

(Jiang, L., & Gao, L. (2005)), using

different preparation techniques, such as

chemical vapour deposition (CVD) (Liu,

J.W., Li, X.J., & Dai, L.M. (2006)) or

vacuum infiltration (Alaf, M., Gultekin, D.,

& Akbulut, H. (2014)). Furthermore, Koh,

J.W. et al. presented the decoration of

MWCNTs with ZnO nanorods applying

hydrothermal method (Koh, J.W. et al.

(2004)). Chen, C.S. et al. synthetised ZnO-

coated MWCNT nanocomposites through

oxidisation and modification of MWCNTs

(Chen, C.S. et al. (2006)). Fu, L. et al.

successfully prepared ZnO-MWCNT-

reduced graphene oxide (RGO)

nanocomposites via one-step hydrothermal

process (Fu, L. et al. (2015)).

As it is well known, the applied synthesis

technique affects the formation of

inorganic layer and particle size on the

surface of CNTs. Recently, different

synthesis pathways were investigated to

produce stable inorganic layers or

nanoparticles on the surface of CNTs,

applying different precursor compounds,

synthesis methods and solvents (Németh,

Z. et al. (2014B)). In hybrid systems,

control of the particle size and morphology

by a facile and low cost method is essential

to their applications. The aim of this work

is to give a comparison between two

synthesis methods (impregnation and

solvothermal method), thus provide further

tools to produce various ZnO/MWCNT

composite materials in a controllable way

concerning both morphology and quality of

inorganic particles. The materials produced

in large quantities can be used in further

nanotechnology processes, for instance

tailored carrier substance for specific

applications or composite additives in

hybrid membranes for water purification.

EXPERIMENTAL

Materials

High purity (90%) MWCNTs with an

average diameter of 10 nm, length of 1.5

µm, surface area 250 m²/g was purchased

from Nanocyl SA, Belgium. MWCNTs

were further purified using diluted (10%)

(HCl), at 60 °C for 6h, followed by a

vacuum filtration and washing with

distilled water until neutral pH was

achieved and then drying at 100 °C for

12h. Figures 1 a,b show SEM image and

the Raman spectrum of purified

MWCNTs. There are three strong peaks at

1 342 cm-1

, 1 572 cm-1

and 2 680 cm-1

which correspond with the D, G and G’

peaks of MWCNTs (Dresselhaus, M.S. et

al. (2005)). The intensity ratios between

these peaks (ID/IG = 0.50, IG’/IG = 0.70 and

ID/IG’ = 0.75) indicate good sp2 structure

and confirm the high-quality of MWCNTs.

Other chemical reagents such as zinc

acetate [Zn(CH₃CO₂)₂×2H₂O] (ZnAC),

absolute ethanol (EtOH) and concentrated

hydrochloric acid (cc. HCl) were obtained

from VWR Chemicals, France.

Preparation of ZnO/MWCNT

composites

ZnO/MWCNT composites were prepared

by two different methods following earlier

studies (Bártfai, E. et al. (2019); Németh,

Z. et al. (2014A)) with some modifications.

The MWCNT content in the total mass of

the final composites was set at 10%.

Briefly, the exact calculated amount of

MWCNT (100 mg) was sonicated in 100

mL of absolute ethanol using the ultrasonic

lab homogeniser (Hielscher GmbH,

Germany) for 15 min and the calculated

amount of zinc acetate 2.42 g (10%) was

dissolved in 50 mL of absolute ethanol and

left under a vigorous stirring using a

magnetic stirrer for 15 min at 300 rpm to

ensure complete dissolution.



__________________________________________________________________________________

18

Fig. 1. SEM image (a) and Raman spectrum (b) of purified MWCNTs



methods

__________________________________________________________________________________

__________________________________________________________________________________19

Afterwards, in the case of impregnation the

solution of the precursor was added drop-

wisely (1 mL/min) to the suspension of

MWCNT then the mixture was allowed to

react under mechanical stirring for 12 h

then heated up to 75 °C then to 100 °C to

remove solvents and finally the final

product was calcinated at 400 °C for 4 h in

a static furnace with 5 °C/min heating rate

to obtain crystalline ZnO nanoparticles.

Applying solvothermal synthesis the

MWCNT suspension was added directly to

the precursor solution under vigorous

stirring and then the mixture was poured

into 150 mL stainless steel autoclaves and

placed in an oven for 12 h at 150 °C.

Subsequently, the final product was

centrifuged to remove solvents and washed

to remove residues, then calcinated for 4 h

at 400 °C. The final products prepared by

impregnation and solvothermal were

denoted ZnO/MWCNT/Imp and

ZnO/MWCNT/Solvo, respectively.

Characterisation

The morphology of the samples was

investigated by scanning electron

microscope. SEM investigation was

performed by a Hitachi S-4800 Type FE-

SEM operating in the range of 0–30

keV. Prior to the measurement the samples

were mounted on a conductive carbon tape.

The energy-dispersive X-ray spectroscopy

(EDAX) measurement was completed with

the scanning electron microscope and a

Röntec XFlash Detector 3001 SDD device.

Raman spectroscopy measurements were

carried out by Thermo Scientific DXR

Raman microscope with a 532 nm laser (5

mW).

RESULTS AND DISCUSSION

SEM and EDAX analysis

After the heat treatment as-prepared

ZnO/MWCNT composites were observed

with SEM and EDAX techniques. The

fabrication of ZnO/MWCNT composites

from ethanol solution was successful using

both of the applied synthesis methods,

although different ZnO layer structures

were observed during SEM observations.

Figure 2 presents representative views at

various magnification of the obtained

ZnO/MWCNT composites materials

prepared with impregnation method, and

these images revealed the presence of ZnO

nanoparticles formed on the surface of

MWCNTs. Image analysis indicated that

the average diameter of ZnO nanoparticles

are in the range of 22±5 nm, although ZnO

particles were sticking together on the

surface of CNTs resulting larger ZnO

agglomerates in some cases. On the other

hand, SEM images confirmed that the

majority of MWCNTs were covered by

ZnO nanoparticles, separated ZnO particles

could not be observed during

investigations.

Figures 3 a-d show SEM images at low

(see Figures 3 a-b) and high (see Figures 3

c-d) magnification of ZnO/MWCNT

composites prepared by solvothermal

method. These images clearly demonstrate

that produced composites contain bigger

ZnO particles with hexagonal structure.

The average diameter of these ZnO

hexagonal are between 2-3 µm. SEM

observations revealed that MWCNTs were

built into the ZnO crystals as it can be seen

in Figure 3. According to Yang, J. et al.

(Yang, J. et al. (2015), ZnO particles with

different morphologies could be observed

by using different solvents, such as water,

ethanol and n-propanol. Based on our SEM

analysis, presumably not only the solvent

but also the applied synthesis technique

could be a determinative factor during the

formation of ZnO particles and the

preparation of ZnO/MWCNT composite

materials. As it can be seen in Figure 3,

ZnO crystallites were aggregated into

bigger hexagonal particles in EtOH

medium during solvothermal synthesis,

due to the surface tension of the solvent.



__________________________________________________________________________________

20

Consequently, the final morphology of the

ZnO/MWCNT composites can be varied

easily by applying the suitable method.

Fig. 2. SEM images (a-b) of ZnO/MWCNT nanocomposite prepared by impregnation

Fig. 3. SEM images (a-d) of ZnO/MWCNT nanocomposite prepared by solvothermal method



methods

__________________________________________________________________________________

__________________________________________________________________________________21

In order to characterise the quality of ZnO

particles on the surface of MWCNTs,

EDAX analyses were performed by the

SEM instrument for each of the samples.

In this study two EDAX spectra are

presented based on the high degree of

similarity of the obtained results (see

Figures 4 a-b). The most significant

signals are originating from carbon (C),

oxygen (O) and zinc (Zn). EDAX analysis

confirms the presence of ZnO and

MWCNT in the composite samples.

Fig. 4. EDX analysis of ZnO/MWCNT nanocomposites



__________________________________________________________________________________

22

Raman spectroscopy

Raman microscopic investigation of the

prepared ZnO/MWCNT samples

confirmed the presence of ZnO and

MWCNTs in the composites. Compared to

the Raman spectra of pristine MWCNT

and Raman spectra of the products exhibits

two peaks at 437 cm-1

and 1151 cm-1

which are characteristic peaks of ZnO (see

Figure 5). Three other strong bands

deriving from MWCNTs appear at 1340

cm-1

, 1574 cm-1

and 2680 cm-1

, attributing

to the D-, G- and G’- bands of MWCNTs,

respectively. The sharp and most intensive

peak at 437 cm-1

in the Raman spectra of

ZnO can be assigned to E2 (high) mode of

ZnO which is the strongest mode in

wurtzite crystal structure (Chandra, A. et al

(2017)). Probably due to the interaction

between the MWCNTs and ZnO particles

the bands slightly shifted as it can be seen

in Figure 5.

Fig. 5. Raman spectra of MWCNT, ZnO and MWCNT-ZnO composites

CONCLUSIONS

The syntheses of zinc dioxide-coated

MWCNT-based composite materials using

two different preparation methods such as

impregnation and hydrothermal were

studied. It can be concluded that these

synthesis methods were successful, but the

structure of composites and the size of the

ZnO particles formed were different. Using

scanning electron microscopy technique it

was verified that different layer

construction and morphology can be

obtained by varying the applied synthesis

techniques. Moreover, Raman

measurements confirmed the presence of

ZnO crystallites on the surface of

MWCNTs and the interaction between

them. Using surface impregnation,

MWCNTs were not completely covered

with ZnO nanoparticles while in the case

of hydrothermal synthesis micrometer size



methods

__________________________________________________________________________________

__________________________________________________________________________________23

ZnO particles were formed. The

differences observed between the two

types of synthesis could be explained by

the disparity of nanocrystallites size of

ZnO. Products of impregnation method

would be ideal candidates as starting

materials in photocatalytic measurements

due to the partially covered MWCNTs

which are involved in the adsorption

process during photocatalysis. The results

made it clear that the best wrappings were

obtained using solvothermal synthesis. The

most important advantage of the

hydrothermal method is that by changing

the concentration of the reactant the

coverage of ZnO particles on the surface of

MWCNTs can be easily controlled.

ACKNOWLEDGEMENTS

The described article was carried out as

part of the EFOP-3.6.1-16-2016-00011

‘Younger and Renewing University –

Innovative Knowledge City – institutional

development of the University of Miskolc

aiming at intelligent specialisation’ project

implemented in the framework of the

Szechenyi 2020 programme. The

realisation of this project is supported by

the European Union, co-financed by the

European Social Fund. Special thanks to

István Slezsák, Dr. and the Innovációs

Laboratórium Kft. (Hungary) to provide us

SEM investigations.

Keywords: ZnO, composite, SEM,

morphology

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Technology, 71(2), 87–94.

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Berkesi, O., Baán, K., Erdőhelyi, A.,

Horváth, E., Veréb, G., Dombi A., Forró, L.,

& Hernádi, K. (2014A). Synthesis,

comparative characterization and

photocatalytic application of SnO2/MWCNT

nanocomposite materials. Journal of Coating

Science and Technology, 1, 137–150.

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Major, J., Horváth, A., Magrez, A., Forró, L.,

& Hernádi, K. (2014B). Chemical challenges

during the synthesis of MWCNT-based

inorganic nanocomposite materials. Physica

Status Solidi B, 251(12), 2360–2365.

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(ed.-s) (2004). The Chemistry of

Nanomaterials: Synthesis, Properties and

Applications. John Wiley.

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M.S. (ed.-s) (1998). Physical Properties of

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H., & Min, C. (2012). A new one-step

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Tóth, András József: Összefoglaló az ÚNKP 18-4-BME-209 kódszámú pályázat kutatásairól

(2018/2019/2)

__________________________________________________________________________________

__________________________________________________________________________________25

Összefoglaló az ÚNKP 18-4-BME-209 kódszámú pályázat

kutatásairól (2018/2019/2)

Tóth, András József

BME-VBK Kémiai és Környezeti Folyamatmérnöki Tanszék, 1111, Budapest,

Budafoki út 8. [email protected], +36 1 463 1494

Beküldve: 2019. június 7. Közlésre elfogadva: 2019. június 15.

KIVONAT

Jelen összefoglaló közleményben a

„Hulladékvíz kezelési módszerek

tanulmányozása a legjobb ipari

technológia megállapítása érdekében”

című, ÚNKP-18-4-BME-209 kódú

pályázat keretében, a 2018/2019/2-es

félévhez köthető, már megjelent

tudományos publikációk eredményeit

mutatjuk be. A kutatott témákat három

nagy csoportba lehet sorolni:

membrános eljárások modellezése,

desztillációs eljárások, és a

membránműveletek és a desztillációs

elválasztás összehasonlítása.

A finomkémiai iparokban a

gyártástechnológia során nagy

mennyiségű folyékony hulladék, ipari

hulladékoldószer keletkezik. Ezek

kezelése kiemelt kérdés, hiszen

ártalmatlanításuk sokszor az egész

technológia költségének a legnagyobb

hányadát teszi ki. Így olyan regenerálási

eljárások kidolgozására van szükség,

amelyek anyagilag kedvezőek a gyár

számára.

MEMBRÁNOS ELJÁRÁSOK

MODELLEZÉSE

A kutatás során mosószer tartalmú ipari

hulladékvizek ártalmatlanítási eljárását

dolgoztuk ki. A kezelések célja a

hulladékvizek kémiai oxigénigény (KOI)

szintjének csatornázhatósági határérték alá

csökkentése. A feladat során először

azonosítottuk a minták szerves anyag-

tartalmát GC-MS módszerrel, majd ezután

laboratóriumi kísérleteket végeztünk.

Különböző fiziko-kémiai hulladékvíz

kezelési eljárásokat vizsgáltunk meg a

minták szerves anyag csökkentésének

céljából: szakaszos üzemű desztillációt,

vákuumbepárlást és különböző

membránműveleteket.

A vizsgálatok nyomán megállapítottuk,

hogy az 1 000 mgO2/l-es csatornázhatósági

határérték alá csökkenthető a technológiai

hulladékvizek KOI-szintje vákuumbepárlás

és fordított ozmózisos eljárás kombinált

alkalmazásával. Két kereskedelmi

forgalomban kapható fordított ozmózisos

membránnal végeztünk laboratóriumi

méréseket. A vizsgálatok során

optimalizáltuk a hozamot és a KOI-

elválasztás hatékonyságát. Továbbá

költségszámításokat is végeztünk,

kiszámoltuk a potenciális csatorna

bírságokat, illetve a kezelések beruházási

és üzemeltetési költségeit. Az eredmények

igazolták a választott kombinált eljárás

gazdaságosságát (Haáz, E. et al. (2019)).

Az 1. ábra mutatja be az eljárás

anyagáramait.

Kutatómunkánk során vizsgáltuk a

hidrofób gázszeparációs membrán eljárás

ammóniacsökkentő hatását ipari szennyvíz

mintákon, illetve emberi vizeleten. A

finnországi Aalto Egyetemen végzett

folyamatos üzemű laboratóriumi

kísérleteket felhasználva, számítógépes

modellt készítettünk a szennyvizes



__________________________________________________________________________________

26

elválasztási folyamat leírására. A

ChemCAD folyamatszimulátorba elsőként

integráltunk kísérleti eredményekkel

verifikált gázszeparációs modult ammónia

elválasztási feladatra.

1. ábra. Mosószer tartalmú technológiai hulladékvizek kezelése bepárlással és fordított

ozmózisos eljárással (Haáz, E. et al. (2019))

A membránreaktort különböző

paraméterek figyelembevételével

optimalizáltuk. Megállapítottuk, hogy

85%-os ammóniacsökkentés érhető el 8 óra

hidraulikus visszatartási idő alatt, 350 liter

kénsav/m2 membránfelület/óra adagolással,

35°C betáplálási hőmérsékleten és 60

membránfelület/reaktor térfogat aránnyal,

vagyis ez a technológia tökéletesen

alkalmas ammónia szennyvíztől való

elválasztására (Nagy, J., Kaljunen, J., &

Tóth, A.J. (2019)). A 2. ábrán látható az

eljárás folyamat szimulátoros modellje.

2. ábra. Gázszeparációs membrán elválasztás modellje a folyamatszimulátorban (Nagy, J.,

Kaljunen, J., & Tóth, A.J. (2019))

DESZTILLÁCIÓS ELJÁRÁSOK

Az extraktív heteroazeotróp desztilláció

(EHAD) eljárásnál az extraktív

desztillációs módszert, ahol vizet

adagolunk be a kolonna legfelső

tányérjára, kombináljuk a heteroazeotróp

desztillációval. A víz segítségével eltoljuk

a gőz-folyadék egyensúlyt és egy

fázisszeparátorral pedig szétválasztjuk a

heteroazeotrópot. Folyamatos

laboratóriumi kísérleteket és

folyamatszimulátoros számításokat

végeztünk több erősen nem-ideális

eleggyel. Hatékonyan alkalmazhatónak

bizonyult az eljárás a víz-aceton-

kloroform-metanol és a víz-etil acetát-

kloroform-etanol elegyek elválasztására.

99,5 tömeg%-os kloroform tisztaságot

sikerült elérni a fejlesztett desztillációs

módszerrel. Maximális forráspontú

azeotrópot tartalmazó elegyet először


(2018/2019/2)

__________________________________________________________________________________

__________________________________________________________________________________27

sikerült hatékonyan elválasztani az EHAD-

módszerrel (Tóth, A.J. et al. (2019)). A 3.

ábrán látható a hibrid eljárás kialakítása

maximális forráspontú azeotrópot

tartalmazó elegy esetében.

3. ábra. EHAD-kolonna kialakítása maximális forráspontú azeotrópot tartalmazó elegy

esetében (Tóth, A.J. et al. (2019))

MEMBRÁNMŰVELETEK ÉS A

DESZTILLÁCIÓS ELVÁLASZTÁS

ÖSSZEHASONLÍTÁSA

Erősen nem-ideális elegyek desztillációval

történő elválasztása összetett és komplex

folyamat. Munkánk során etanol-etil

acetát-víz (1), metanol-etil acetát-víz (2),

illetve metanol-izopropil acetát-víz (3)

elegyek elválasztását vizsgáltuk

desztillációs és membrános módszerek

kombinációjával. Laboratóriumi

kísérleteket, számítógépes modellezéseket

és költségszámításokat is végeztünk. A

ChemCAD folyamatszimulátort és a

Douglas-költség függvényeket használtuk.

Az optimalizálás során megkerestük a

legkisebb extraktív ágens (víz)

beadagolásának mennyiségét, amivel

teljesíteni lehet az azeotrópok bontását a

kolonnában. Megállapítottuk továbbá a

minimális elméleti tányérszámot, a

refluxarányt és a hőszükségleteket is.

Összességében elmondható, hogy az

EHAD-eljárással szét lehet választani

azeotróp párokra az elegyeket. Ha 99,5

tömeg%-os terméktisztaságot szeretnénk

elérni mindegyik komponens esetében,

akkor összetett eljárás szükséges. Az

etanol alapú rendszernél a nyomásváltó

desztillációt (PSD) kombináltuk az etilén

glikollal végzett extraktív desztillációval

(ED) (1. módszer), a PSD-t a

desztilláció/hidrofil pervaporáció

kombinációjával (D+HPV) (2. módszer). A

3. módszer az EHAD+PSD és ED, a 4.

pedig az EHAD+PSD és D+HPV

kombináció volt. Megállapítottuk a

módszerek költségalapú optimalizálása

során, hogy az extraktív heteroazeotróp

desztilláción alapuló nyomásváltó

desztilláció kombinálása hibrid,

desztillációs-pervaporációs elválasztással

(4. módszer) bizonyul a legkedvezőbbnek

(Haáz, E. et al. (2019B)). A 4. ábra

foglalja össze az eljárásokat a teljes költség

szempontjából.



__________________________________________________________________________________

28

4. ábra. Etanol-etil acetát-víz terner elegy elválasztási lehetőségeinek összehasonlítása (Tóth,

A.J. (2019))

A metanolos elegyek ((2) és (3)) esetében

megállapítottuk, hogy az EHAD-kolonna

fenéktermékeként keletkező metanol-víz

elválasztása kapcsán csökkenthetők a

költségek hidrofil pervaporáció

alkalmazásával (Haáz, E. et al. (2019)).

KÖSZÖNETNYILVÁNÍTÁS

A publikáció az Emberi Erőforrások

Minisztériuma ÚNKP-18-4-BME-209

kódszámú ’Új Nemzeti Kiválóság

Programjának, a Nemzeti Tehetség

Program NFTÖ-18-B-0154’ pályázatának,

a Bolyai János Kutatási Ösztöndíjnak, az

112699-es és az 128543-as számú OTKA

pályázatok támogatásával készült. A kutató

munka az Európai Unió és a magyar állam

támogatásával, az Európai Regionális

Fejlesztési Alap társfinanszírozásával, a

GINOP-2.3.4-15-2016-00004 projekt

keretében valósult meg, a felsőoktatás és

az ipar együttműködésének elősegítése

céljából.

HIVATKOZÁSOK

Haáz, E., Fózer, D., Nagy, T., Valentinyi, N.,

Andre, A., Mátyási, J., Balla, J., Mizsey, P.,

& Tóth, A.J. (2019A). Vacuum evaporation

and reverse osmosis treatment of process

wastewaters containing surfactant material:

COD reduction and water reuse. Clean

Technologies and Environmental Policy,

21(4), 861–870.

doi: 10.1007/s10098-019-01673-5

Haáz, E., Szilágyi, B., Fózer, D. & Tóth, A.J.

(2019B). Combining extractive

heterogeneous-azeotropic distillation and

hydrophilic pervaporation for enhanced

energetic separation of non-ideal ternary

mixtures. Frontiers of Chemical Science and

Engineering,

doi: 10.1007/s11705-019-1877-1

Nagy, J., Kaljunen, J., & Tóth, A.J. (2019).

Nitrogen recovery from wastewater and

human urine with hydrophobic gas separation

membrane: experiments and modelling.

Chemical Papers, 73(8), 1903–1915.

doi: 10.1007=s11696-019-00740-x

Tóth, A.J. (2019): Comprehensive evaluation

0

500

1000

1500

2000C

ost

[1

00

0$

/y]

Operating cost Investment cost

https://link.springer.com/article/10.1007/s10098-019-01673-5









https://doi.org/10.1007/s11705-019-1834-z

https://www.sciencedirect.com/science/article/pii/S1383586618344058


(2018/2019/2)

__________________________________________________________________________________

__________________________________________________________________________________29

and comparison of advanced separation

methods on the separation of ethyl acetate-

ethanol-water highly non-ideal mixture,

Separation and Purification Technology,

224, 490–508.

doi: 10.1016/j.seppur.2019.05.051

Tóth, A.J., Szilágyi, B., Haáz, E., Solti, Sz.,

Nagy, T., Szanyi, Á., Nagy, J., & Mizsey,

P. (2019). Enhanced separation of

maximum boiling azeotropic mixtures with

extractive heterogeneous-azeotropic

distillation. Chemical Engineering Research

and Design, 147, 55–62.

doi: 10.1016/j.cherd.2019.05.002

















__________________________________________________________________________________

30

Beszámoló a 29th European Symposium on Computer Aided

Process Engineering (ESCAPE29) rendezvényről (Eindhoven,

2019. június 16–19.)

Tóth, András József

BME-VBK Kémiai és Környezeti Folyamatmérnöki Tanszék, 1111, Budapest,

Budafoki út 8. [email protected], +36 1 463 1494

Beküldve: 2019. június 20. Közlésre elfogadva: 2019. június 25.

Idén Hollandiában, Eindhoven-ben került

megrendezésre az ESCAPE29 konferencia

június 16–19. között.

A konferencia szekciói az alábbiak voltak,

zárójelben a vezetőjük:

1. Process-product synthesis, design

and integration (Mariano Martin

(University of Salamanca, Spain))

2. Methods, models and

computational tools for PSE

(Alexander Mitsos (RWTH Aachen

University, Germany))

3. Process control and operations

(Paul van den Hof (Eindhoven

University of Technology, The

Netherlands))

4. CAPE/PSE in sustainable

development and food industry

(Albert van der Padt (Wageningen

University, FrieslandCampina, The

Netherlands)) & Antonis Kokossis

(National Technical University of

Athens, Greece))

5. CAPE/PSE in energy transition

(Stratos Pistikopoulos (Texas A&M

Energy Institute, US))

6. CAPE/PSE in hi-tech micro/nano-

devices and processes (Ruud van

Ommen (Delft University of

Technology, The Netherlands))

7. Education in CAPE/PSE &

knowledge transfer (Antonio

Espuña (Universitat Politècnica de

Catalunya, Spain))

A rendezvény fő támogatói a Royal Dutch

Shell, a BASF és a DOTX Control

Solutions voltak. A konferenciát megnyitó,

plenáris előadást Joseph Powell (Chief

Scientist, Shell, USA) tartotta „Addressing

energy and sustainability challenges in the

digital age” címmel.

A rendezvényen a Környezeti és

Folyamatmérnöki Kutatócsoport az alábbi

két előadással képviseltette magát:

Andras Jozsef Toth (előadó), Daniel Fozer,

Tibor Nagy, Eniko Haaz, Judit Nagy, Peter

Mizsey: Modelling of extractive

heterogeneous-azeotropic distillation in

dividing wall column (in English), 29th

European Symposium on Computer-Aided

Process Engineering (ESCAPE-29),

Eindhoven, The Netherlands, 16–19. June

2019., pp. 235–240.

Tibor Nagy (előadó), Florian Enyedi,

Eniko Haaz, Daniel Fozer, Andras Jozsef

Toth, Peter Mizsey: Flexible and efficient

solution for control problems of chemical

laboratories (in English), 29th European

Symposium on Computer-Aided Process

Engineering (ESCAPE-29), Eindhoven,

The Netherlands, 16–19. June 2019., pp.

1819–1824.

Az ESCAPE29 konferencia tudományos

publikációi a 2019-es Computer Aided

Chemical Engineering folyóiratban

jelentek meg.

https://www.sciencedirect.com/bookseries/computer-aided-chemical-engineering

https://www.sciencedirect.com/bookseries/computer-aided-chemical-engineering

Tóth, András József: Beszámoló a 29th European Symposium on Computer Aided Process

Engineering (ESCAPE29) rendezvényről (Eindhoven, 2019. június 16–19.)

__________________________________________________________________________________

__________________________________________________________________________________31

A következő ESCAPE konferencia

Milánóban lesz 2020. május 24-27 között

megtartva, ahová az alábbi linken lehet

jelentkezni:

https://www.aidic.it/escape30/index.html

Ezúton szeretnék köszönetet mondani az

MTA Bolyai János Kutatási Ösztöndíj

támogatásának.

Tóth András József

Logó forrása: https://escape29.nl/

https://www.aidic.it/escape30/index.html

https://escape29.nl/



__________________________________________________________________________________

32

Környezetorientált Szén-dioxid Partnerség (ECO2P) a Miskolci

Egyetemen

Korunk környezetvédelmi kihívásainak

megfelelni kívánva, a Miskolci Egyetem

2018. január 10-én megalapította

a Környezetorientált Szén-dioxid

Partnerséget (Environmental Carbon-

dioxide Partnership)

A Partnerség lehetőséget biztosít a hazai és

nemzetközi szakembereknek,

intézményeknek, vállalatoknak, hogy

rendszeresen, szervezett keretek között

megtárgyalhassák problémáikat és

egyeztethessék megoldásaikat. A

Partnerség keretein belül létrejött munka

lehetőséget biztosít az innováció gyorsabb

terjedésére, közös pályázatokra, szorosabb,

hatékonyabb együttműködésre.

Alapító tagok: - Wanhua-BorsodChem Zrt.,

- Linde Gáz Magyarország Zrt.,

- Kiss Cégcsoport,

- ÉMK Észak- magyarországi

Környezetvédelmi Kft.,

- Nemzeti Közszolgálati Egyetem,

Katasztrófavédelmi Intézet,

- Ábrahám József,

- MOL Nyrt (állandó meghívott),

- Miskolci Egyetem.

A Partnerségben a szakmai munka

megoldásokat kínál:

az antropogén eredetű szén-dioxid

emisszió csökkentésére,

a megújuló alapú energia hatékony

tárolására,

az energiatárolással párhuzamosan

elvégezhető megújuló alapú nyersanyag

gyártása.

Ez a három kihívás egyidejűleg is

megoldható, ha a szén-dioxidot tekintjük

a körforgásos gazdaság platform

molekulájának.

A szakmai munka két szinten zajlik

technológiai szinten és

makrogazdasági szinten.

A technológiai szinten kidolgozzuk és

egymáshoz illesztjük a szén-dioxid alapú

körforgásos energiagazdaság hatékony

elemeit, úgymint:

- CCU, Carbon Capture and

Utilization;

- tiszta szén technológiák bevonása;

- alga szén-dioxid hasznosítási

képességének vizsgálata;

- a hidrogén előállítása megújuló

alapon előállított elektromos

árammal történő vízelektrolízis

segítségével;

- a szén-dioxid átalakítása

hidrogénnel metánná (földgáz)

vagy metanollá;

- az energiatermelési céllal előállított

metán és/vagy metanol képezik a

megújuló nyersanyagellátás alapját,

(l.. Oláh György,

Metanolgazdaság);

- energiatermelés az előállított

metánból vagy metanolból;

A makrogazdasági szinten a kutatás

- a technológiai szinten elért

eredmények birtokában vizsgálja és

megállapítja a módszer hatékony

alkalmazhatóságának körülményeit,

tekintve a folyamatok fluktuáló

jellegét;

- vizsgálni kell az energiatárolással

párhuzamosan megoldható

megújuló alapú nyersanyaggyártás

gazdaságossági paramétereit és az

energiatároláshoz való viszonyát;

- megállapítja a szén-dioxid

hasznosítás és az energiatárolás, ill.

nyersanyaggyártás gazdaságos

kivitelezhetőségének társadalmi,

gazdasági körülményeit;

Környezetorientált Szén-dioxid Partnerség (ECO2P) a Miskolci Egyetemen

__________________________________________________________________________________

__________________________________________________________________________________33

- a körforgásos energiagazdálkodás

fogyasztásra gyakorolt hatását és

társadalmi jelentőségét vizsgálja.

A Miskolci Egyetem várja mindazon

érdeklődőket, akik a Partnerségben az

említett területek bármelyikén jártassággal

rendelkeznek, azt kutatják és/vagy

bármelyik területen együtt szeretnének

működni valakivel.

A Partnerség tevékenységét nem kívánja

korlátozni a szén-dioxiddal való

tevékenységre, hanem más,

környezetvédelmi feladatokkal is

foglalkozni kíván.

A partnerségi tagság a következő

lehetőségeket, előnyöket kínálja: hazai és nemzetközi

szakembereknek, intézményeknek,

vállalatoknak, hogy rendszeresen,

szervezett keretek között, félévente

megtárgyalhassák problémáikat és

egyeztethessék megoldásaikat,

a Partnerség keretein belül létrejött

munka lehetőséget biztosít

az innováció gyorsabb terjedésére,

közös pályázatokra,

szorosabb, hatékonyabb

együttműködésre.

Természetesen a szén-dioxidon

kívül más problémák vizsgálatára és más

lehetőségek felkínálására is van/lesz

lehetőség a Partnerség tagjainak igényei,

illetve kínálata szerint.

(A http://eco2p.eu/ honlapról kis

változtatással átvett közlemény)

http://eco2p.eu/

körforgásos gazdaság és környezetvédelemsolution on sacrificial polyurethane and zeolite foam...

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