05双极膜的应用.pdf

CleaCleanniingng ttiionon
-------- Production of anic acid and base
twxu Green technology and BP process
CleaCleanniingng ttiionon
-------- Production of silicic acid (H2SiO3)
Conventional process---
Ion exchange method:Energy consumption >1 kwh/kg products
Bipolar membrane
electrodialysis(BPE):Energy consumption > kwh/kg products; Operation conditions :
2
V=-4V(I=10-12 mA/cm ), h=55-75%, Sio2=6-10%, pH=3.
twxu Green technology and BP process
CCeellll aarrrrananggeemmenenttss ooff icic acacidid
ttiionon
twxu Green technology and BP process
CleaCleanniingng ttiionon
---- Production anic acid
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twxu Green technology and BP process
PPililotot ttestest----onfonfiigugurraattiiononss ofof cicittrricic
aciacidd ttiionon
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0 50 100 150 200 250 0 25 50 75 100 125
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Time (min) Current density ( )
Current efficiencies for citric acid production Energy consumption for the production of
versus time at i=100 -2. citric acid production versus current density.
Refs:XuT W et al, Chem. Eng. process, 2001, in press
XuT W et al, J Membr. Sci., 2001, revised
twxu Green technology and BP process
PPililotot ttestest----ResResuullttss ofof cicittrricic acidacid
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C 0
0 50 100 150
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0 50 100 150 200 Current density ( )
Time (min) Energy consumption for the production of
Current efficiencies for citric acid production citric acid production versus current density.
versus time at i=100 -2.
Na3Cit, Na2SO4; Na3Cit, 0