Download - Top-down approach 長庚化材系 郭修伯. Grinding l 粗碎: n m 級 to 10 cm 以下 n Jaw crusher n Gyratory crusher
Top-down approach
長庚化材系郭修伯
Grinding
粗碎: m 級 to 10 cm 以下 Jaw crusher Gyratory crusher
Grinding
中碎: 10 cm to 1 cm 以下 ; Crushing roll
Grinding
中碎: 10 cm to 1 cm 以下 ; Hammer mill & Roller mill
Grinding
微粉碎: 1 cm to 10 micron 以下 ; roller mill, jet mill, ball mill,
vibration mill, planetary mill
Low temperature increasing 大小 ball 分佈;最適回轉數 )m(D
32)rpm(N
Grinding
微粉碎: 1 cm to 10 micron 以下 ; roller mill, jet mill, ball mill,
vibration mill, planetary mill
40-50 % fill, several g
Grinding
超微粉碎: 10 micron to 1 micron 以下 ; 介質攪拌型粉碎機 ,
vibration mill, planetary mill
Surface charge distribution
The distributions of ions and counter ions are controlled by Coulomic force or electrostatic force Entropic force or dispersion Brownian motion
Inhomogenous distribution double layer structure separated by the Helmholtz plane
Fig 2.14
Van der Waals attraction potential
The sum of the molecular interaction for all pairs of molecules weak force and becomes significant only at a
very short distance agglomeration of nanoparticles: the
combination of van der Waals force and Brownian motion
Prevent agglomeration: electrostatic repulsion and steric exclusion
Electrostatic repulsion stabilization
Fig 2.18
Steric exclusion stabilization
Also “polymeric stabilization” Widely used in stabilization of colloidal
dispersions thermodynamic stabilization: particles are
always redispersible high concentration can be accommodated not electrolyte sensitive suitable to multiple phase systems
Polymeric stabilization
Fig 2.21
Gas phase particle formation
Gas phase particle formation, CVD
Gas phase particle formation, CVD
Gas phase particle formation, CVD
Formation of particles in solutions
Formation of particles in solutions
Formation of particles in solutions, chemical methods
Formation of particles in solutions, physical methods