Study Of Preparation And Application Properties Of Chitosan Quaternized With CTA

The optimum synthesis conditions of cationic 2-hydroxypropyltrimethyl-ammonium chloride chitosan (HTCC) was determined according to the turbidity removal efficiency for kaolin suspension, the mass ratio of mCTS:mCTA:mNaOH=1:2:1.2, reaction temperature for 60℃and reaction time for 7h; The results of infrared spectroscopic analysis by HTCC and CTS showed that HTCC was prepared by CTS modified with CTA; Water-solubility of HTCC improved evidently compare to CTS, and it enhancing with increasing degree of substitution of HTCC; The turbidity removal efficiency of HTCC for kaolin suspension more than CTS,suitable scope of pH for HTCC was broader than CTS,and the best dosage of HTCC reducing almost 30% as chitosan.The experiment showed that the turbidity removal rate of HTCC for kaolin suspension increases with the increase of molecular weight and the degree of deacetylation of chintosan; The influence of settling time and dosing concentration on turbidity removal are not obvious; To extend slowly stir time can increase turbidity removal rate of HTCC; Both the turbidity removal rate and residual turbidity of the water sample at the optimum dosage of HTCC/PAC gradually higher with increasing in the original turbidity;And the higher water temperature make for HTCC to flocculate kaolin suspension.When HTCC combined with PAM for flocculating kaolin suspension, the best molecular weight was from fourteen million to seventeen million and its best composite ratio was determined to be mHTCC:mPAM=16.67:1;For (?)riginal water of 97.85NTU turbidity, the turbidity removal rate reaches above 96% and residual turbidity reaches under 4 NTU by HTCC/PAM with this composite ratio. The turbidity removal efficiency of HTCC/PAM for kaolin suspension more than HTCC and PAM added seperately, and suitable scope of pH for HTCC/PAM was broader than HTCC and PAM; The flocculation effects of first dosing HTCC better than first dosing PAM; The influence of settling time on turbidity removal is not obvious, indicating the settling is very quick; Both the turbidity removal rate and residual turbidity of the water sample by HTCC/PAM gradually higher with increasing in the original turbidity; And the higher slow stir speed contribute to increase turbidity removal efficiency and decrease residual turbidity.HTCC combined with PAC for flocculating kaolin suspension was investigated, and its best composite ratio was determined to be mHTCC:mPAC=1:1.6. For original water of 97.85NTU turbidity, the turbidity removal rate reaches above 98% and residual turbidity reaches under 2 NTU by HTCC/PAC with this composite ratio. The turbidity removal efficiency of HTCC/PAC for kaolin suspension more than HTCC and PAC added seperately, and suitable scope of pH for HTCC/PAC was broader than HTCC and PAC; HTCC/PAC composited by the solid-solid way is less efficient than the liquid-liquid way; The influence of settling time and HTCC or PAC separate dosing sequence on turbidity removal is not obvious;Both the turbidity removal rate and residual turbidity of the water sample at the optimum dosage of HTCC/PAC gradually higher with increasing in the original turbidity; For the original water of low turbidity, the dosage should be increased to reach lower residual turbidity; The residual aluminum of the water treated by HTCC/PAC is obviously lower than the PAC treated water, and also apparently lower than the aluminum permission content of National Drinking Water Standard.The turbidity removal efficiency about Lanzhou section of the Yellow River water by composite flocculants HTCC/PAM more than HTCC and PAM added separately; The removal rate of the turbduty get to the best at the optimum dosage of HTCC/PAM with the composite ratio of mHTCC:mpAM=14.29:1, and the residual turbidity reaches under 7 NTU;The influence of settling time on turbidity removal by HTCC and HTCC/PAM is not obvious; The pH has great influence on the turbidity removal efficiency of HTCC and HTCC/PAM, and lower pH value contribute to enhancing flocculation performance and reducing the dosage; The turbidity removal efficiency get to the best when pH value is 5 and the residual turbidity reaches under 2 NTU; And the flocculation effects of first dosing HTCC better than first dosing PAM.The removal rate of the turbidity about Lanzhou section of the Yellow River water by composite flocculants HTCC/PAC more than HTCC and PAC added separately (?) The turbidity removal efficiency get to the best at the optimum dosage of HTCC/PAC with the composite ratio of mHTCC:mpAc=1:3, and the residual turbidity reaches under 3 NTU; The flocculation effects of first dosing PAC a bit better than first dosing HTCC when HTCC combined with PAC; The influence of settling time on turbidity removal is not obvious; The turbidity removal efficiency of HTCC/PAC composited by the liquid-liquid way more than the solid-solid way;The pH has great influence on the turbidity removal efficiency of HTCC/PAC, and it reaches a good flocculation performance when pH is between 7 and 9; And the turbidity removal rate is gradually slowing when pH is from 5 to 7, but the optimum dosage of HTCC/PAC become smaller; The flocculation performance of HTCC/PAC compounded by the solid-solid way is less efficiencies than the liquid-liquid way.The flocculation effciency about styrenebutadiene rubber wastewater by composite flocculants HTCC/PAC more than HTCC and PAC added separately, the residual turbidity reaches under 2 NTU, and the removal rate of CODcr and chromaticity are separately reach to 92.98% and 32.0%; The suitable pH value scope for flocculating the sample by HTCC/PAC is from 6 to 8; They all have a good turbudity removal efficiency about styrenebutadiene rubber wastewater such as HTCC/PAMYin,YL/PAMYang and PAC/PDMDAAC, the residual turbidity reaches under 3 NTU, and that the removal of CODcr by HTCC/PAMYin reach to 46.01% obviously higher than YL/PAMYang (31.02%) and PAC/PDMDAAC (23.53%); And HTCC-PAMYin have a good flocculation performances when pH value during 5 to 10.When HTCC used for processing practical wastewater, it has many advantages such as simplicity of operation and better treatment effect; It also can come into being good economic results in society and has stronger value of application.