Adsorption And Decolorization Of Amaranth In Deying Wastewater On QACC

Azo dyes play an important role among aromatic compound dyes while been widespread used during all kinds of industries such as textile printing,agriculture,medicine,cosmetics,etc.As we all known,a large amount of chemical properties complicated,recalcitrant and high chrome dyeing wastewater has been produced during the process of dyes using.Decoloration was one of the main target during dye wastewater treatment.Absorbent decolorant and bio-degradation have been most widely researched or used among those methods of dyeing wastewater treatment nowadays.However,secondary pollution and low decolorant rate were restricted conditions of these two methods.A new method material which contain advantages and disadvantages deleted of both two methods should be developed in decoloration.Cellulose was highly focused on cause it's advantages of widely-spread,functional modification capable and well biocompatibility during environment control.Cellulose as the decolorization material in this study,was dissolved in Na OH/Urea/Deionized water and etherificating modified by CAPTAC,then the Quaternary ammonium cationic cellulose(QACC)had been produced.Characteristics of cellulose Saturated adsorption capacity,adsorption equilibrium time and proportion between QC-7 and AR were defined according to researches about adsorbing capacities of modified cellulose to amaranth dye.Ultraviolet Spectrum Analysis and analysis on the changes of enzyme system during decolorization helped to speculate how QC-7enhances the AR decolorization.The main results of this study would be shown below:(1)The molar ratio of CAPTAC and cellulose unit affect the degree of the quaternary ammonium cationic cellulose and cationic degree significantly,the QC-7 was the best absorbent material while CAPTAC/AGU=7.(2)The time of equilibrium sorption was 1.5 h,the saturated sorption capacity of QC-7 was about 360mg/g,while the sorption process was mainly chemical sorption and p H rang 3 to 9.The adsorption capacity can make full use when the dosing ratio of QC-7/AR?4,and dosing ratio of QC-7/AR>4 proving that QC-7 serves as a flocculating agent in the sorption system.(3)Absorbent experiment of modified cellulose to AR shown that adsorbent process of QC-7 accorded with the pseudo-second-order kineticsequation.Equilibrium sorption followed Langmuir isothermal sorption and Dubinin-Radushkevich mode.Adsorptionproces mainly accorded with chemical adsorption monolayer adsorption.(4)QC-7 performed well in recycling:QC-7-AR was adsorbed and recycled by desorbed solution 0.1 mol/L Na OH and then 0.1 mol/L HCl.The regeneration rate could be more than 95% after recycling for 5 times and the rate would be more than 90% at a8 times recycling.The biological regeneration of QC-7-AR cost a longer time by itself until adding the redox mediator AQS.The biological regeneration focused on AR degradation and lowered polution during secondary usage.(5)The enhancement of bio-decolorization by Pseudomonas sp.on amaranth dye could be realized by QC-7.The optional dosage of QC-7 was 100 mg/L.In addition,the p H range of the decolorization of wastewater could be enlarged by QC-7,which improved the tolerance concentration to AR to 150 mg/L.The efficiency of biodecolorization by Pseudomonas sp.and AQS was obviously improved.(6)The dominant mechanism of enhancement provided by Pseudomonas sp.and AQS during bio-decolorization of QC-7 on amaranth was investigated.