FeO : O : A NH 2, NH + NaOH H 3 PO 4, ; DF1720SB5A. Vol. 12 No. 1 Feb ELECTROCHEM ISTRY : (2006)

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1 ELECTROCHEM ISTRY Vol. 1 No. 1 Feb. 006 : (006) FeO 4 -,,, 3 (, ) :, % H SO 4 1% H SO 4. ( ),. Nafion,,. : ; FeO 4 - ; ; : O : A,,,,.,,. Nafion,,, Nafion. 1 Fig. 1 Structure of the chitosan ( (1, 4) D ), ( 1, 4 ) [ 1 ].., Lee Shin ; [ ]., [ 3 ],. NH,, HAc : NH H O NH + H 3 O + (1), NH + 3,.,,, % 36% H SO 4 NaOH H 3 PO 4, ; DF170SB5A ( ) ; IR408 ( ) : , : , Tel(86591) ; zc14@publ. fz. fj. cn (04FSD), (04K06)

2 IR; XL30ESEM ( ). 1. [ 4 ] 1% 1. 5%,,, CS (Chitosan). CS 4% NaOH, m in,, % H SO 4, 40, MCS (Modified chitosan membrane). 1% H SO 4 5 m in ), 4 h,,,, SI = [ (W w - W d ) /W d ] 100% () W w ( g),w d ( g). ) 1. 5 g ( ), 50 ml, 50 ml 1 mol/l NaCl H +,,., 0. 1 mol/l NaOH NaCl H +,. : Exchange Capacity = V NaOH C NaOH (mmol/g) (3) W w, NaOH (C NaOH ) mmol/ml, V NaOH NaOH (ml) ( ), ( Q35, C% 01% ), Pt, 14 mol/l NaOH.,,. 1. 5, 1 mol/l Na SO 4, NaOH. OH -,OH - HCl, FeO 4-14 mol/l NaOH, 30,. 60 m in, 30 m in, [ 5 ] FeO - 4. ( 4) (5), (6). Fe + 8OH - - FeO 4 + 4H O + 6e - (4) H O + e - H + OH - (5) 4OH - H O + O + 4e - (6) Fig. Sketch map of the bicathode electrobath for the p reparation of ferrate. 1,, [ 6 ]., CS, MCS,, 45. 9%. 1 CS Nafion. 1 MCS CS Nafion Tab. 1 Comparison of the physical p roperties between the MCS and CS, Nafion menbiance Physical p roperties CS MCS Nafion Swelling index/% [ 7 ] Exchange capacity/mmol L [ 4 ] :,. H SO 4,. 3 [ 8 ].

3 1 : FeO Fig. 3 Mechanism of p rotonation for the modified chitosan membrane 4 CS (A) MCS (B) Fig. 4 TEM images of the chitosan membrane (CS) and modified chitosan membrane (MCS) 3 [ 6 ] : CS NH HAc CS NH + 3 NaOH CS NH + 3 OH - H SO 4 CS NH + 3 SO - 4 (H + ) (7). SEM 4 (A B ) : CS, MCS,,,,. (C) m, 0 m.. 3 FTIR [ 910 ] 5 CS MCS. : 1 55 cm - 1 (N H ), cm - 1 C N, 1 15 cm cm - 1, 1 07 cm cm - 1 C O., % 1% H SO 4, cm cm - 1 SO ) 5 CS (A) MCS (B) Fig. 5 IR spectra of the CS(A) and MCS membrane (B) FeO 4 -. FeO 4 - ; OH - Cl - B r - F - SO - 4 NO - 3 [ 11 ], OH - FeO 4 - OH - [ 113 ].,

4 CS MCS Tab. Comparation of the IR between CS and MCS membrance CS/cm - 1 MCS/cm - 1 Function group s NH, OH C H C H NHCOCH 3, C O (N H) C N OSO 3, S O C O D C O S (MCS), FeO ) FeO 4 3 MCS Nafion,, 30, 0 ma /cm 40 ma /cm, 10 m in FeO - 4.,, FeO - 4., MCS, FeO - 4 OH -,. ) 6 ( ), MCS Nafion, h OH -. : MCS Nafion OH -., (MCS) OH - Nafion., - MCS Nafion, FeO 4, FeO - 4 OH -, OH -., Nafion,, 3 FeO 4 - Tab. 3 Ferrate (V I) membranes after electrolyte Current density /ma cm - MCS/mol L - 1 concentration depend on the different Nafion /mol L Expeyimental condiction: T = 30, 14mol/L NaOH electro lyte, m ild steel as anode 3 1) % H SO 4 1% H SO 4 (MCS),. ) MCS, OH -, FeO OH - Fig. 6 Transfer concentration of OH - in different current densities (R efe rence s) : [ 1 ] ZHEN Q iuyang, BAO Zhensong. Effects of surfactant and acid type on p reparation of chitosan m icrocap sules [ J ]. China Particuology, 004, () : [ ] H ideto Matsuyama, H ideto Shishiraishi. Effect of mem brane p reparation conditions on solute permeability in chitosan membrane[ J ]. Journal of App lied Polymer Sci ence, 1999, 73: [ 3 ] YING W an, Katherine A M. Creber. Synthesis, char acterization and ionic conductive p roperties of phospho rylated chitosan membranes. macromol [ J ]. Chem.

5 1 : FeO 4-39 Phys., 003, 04: [ 4 ] Nelsen L, Cross R A, V igen M A., et al. Synthetic thromboresistant surfaces from sulfonated polyelectrolyte comp lexes[ J ]. Surgery, 1970, 67 : [ 5 ] Schreyer J M, Thomp son G W, Ockerman L. Oxidation of chrom ium ( III) with potassium ferrate (V I) [ J ]. A nal. Chem., 1950, (11) : [ 6 ] WAMG Xiaop ing( ), YU Zhaoxiang( ). Preparation and p roperties of chitosan /pectin polyelec trolyte comp lex [ J ]. Chem ical World, 00, (5) : [ 7 ] L IU Fuqiang ( ), X ING Danm in ( ), et al. Nafion / PTFE composite membrane for PEMFC [ J ]. Electrochem istry, 00, 8 (1) : [ 8 ] Tiekea B, Van F, Ackern L, et al. U ltrathin selfassem bled polyelectrolyte multilayer membranes[ J ]. Phys. J. E, 001, 5: [ 9 ] Byun H S, Burford R P, et al. Sulfonation of cross linked asymmetri membranes based on polystyrene and divinylbenzene [ J ]. App lied Polymer Science, 1994, 5: [ 10 ] Mokrini A., Acosta J L. New ion conducting system s based on star branched block copolymer[ J ]. Polymer, 001, 4: [ 11 ] Unnikrishnan E K, Kumar S D. Permeation of inorgan ic anions through nafion ionomer membrane[ J ]. Mem brane Sci., 1997, 15: 69. [ 1 ] CHEN Zhen, Okum i Z, Takehara Z I. App lication of the SPE mothod to organic electrochem istry. X II. lead dioxide as a mediator for electrooxidation of cinnamyl alcohol on Ptnafion[ J ]. Bull. Chem. Soc. Jpn., 1991, 64: 161. [ 13 ] CHEN Zhen, M izoe T, Okum i Z, et al. App lication of the SPE mothod to organic electrochem istry. X I. influ ence of the solvent on electrooxidation of cinnamyl al cohol on Ptnafion [ J ]. Bull. Chem. Soc. Jpn., 1991, 64: 537. Electrogenerated FeO - 4 Using M odified Chitosan Cation Exchange M embrane ZHONG Huaizhen, CHEN R iyao, ZHENG Xi, CHEN Zhen 3 (College of Chem istry and M ateria ls Science, Fu jian N orm al U niversity, Fuzhou , Fu jian, Ch ina) Abstract: The chitosan cation membrane was p repared by crosslinked % and doped with 1% H SO 4. p roducts were marked as MCS. The physical p roperties and the ion exchange capacity of MCS were studied. Compared to the nonmodified membrane, it was found that chem ical modifications contributed to imp roving ion exchange capacity from 0. 5 to. 09 meq /g. Resultswas also suggested that the MCS can be used as a separator when p roducing sodium ferrate flocculent using electrochem ical p rocess. Ke y wo rd s: Chitosan, Modification, Cation exchange m embrane, Electrolyte The