Preparation Activated Carbon From Waste Filter Bags And Its Advanced Treatment On Dyeing Wastewater

Waste filter bags (WFBs) are one of the fastest growing industrial wastes in china, The raw material of WFBs mainly consists of synthetic chemical fibers-which are high in carbon and have poor in bio degradability-that is most important to prepare activated carbon (AC). AC adsorption is one of the most widely used processes due to its simple operation and methodology. Dyeing wastewater must be treated by physical、chemical and biological method to satisfy the emission control regulations. In this paper, WFBs was used to prepare AC, and advanced treatment on dyeing Wastewater. Aniline on WFBAC were determined from batch tests, the efficiency of the activated carbon prepared from waste filter bags (WFBAC) was compared with that of the commercial activated carbon (CAC) in this study.The WFBs used for the preparation of AC were obtained from the manufacturing processes in a furniture plant in Dongguan City, Guangdong Province, China. The elemental analysis and the proximate analysis of WFBs shown that the volatiles of WFBs was high to 87.57%, C% was 62.2% and the fix carbon was 9.55%。WFBs were used as precursor for AC preparation by chemical activation. The effects of activation parameters (temperature, heating rate and NaOH:chars impregnation rate), carbonization time and activated agent (NaOH, ZnCl2 and H3PO4) on the performance of AC on adsorption removal of aniline from aqueous solution were selected to investigate.2 h of carbonization time、1:2 of chars impregnation rat、600℃ of activation temperature、8℃/min of activated rate and chemical activated by NaOH was obtained that more suitable for aniline uptake. The activation parameters for the prepared of AC were optimized using central composite design (CCD) method, and the yields of activated carbon along with its adsorption capability for aniline were described by two quadratic models. The results revealed that the optimum conditions for the production of WFBAC for aniline adsorption were activation temperatures 621.56℃, activation heating rate 8.39℃/min and chars impregnation rate 0.71 under which up to 30.77% of AC yield was achieved and the adsorption potentialities of AC to aniline can reach 369.97 μg/g, and the iodine number was 834.14 mg/g.The FTIR showed that the function groups has a great change after activation:the more intense of alkaline groups, the less intense of acid groups. It was indicated that the aniline adsorption capability was improved. The SEM clearly observed that porous structure was developed on the surface of AC development.Adsorption kinetics and isotherms of aniline on WFBAC were determined from batch tests. The effect of contact time, adsorbent dosage and adsorption temperature were also investigated. The highest aniline removal rate using prepared AC at an aniline concentration of 0.104 mg/L reached 94%, while the removal rate was only 87% for a CAC. Adsorption equilibrium was reached at 60min for the WFBAC-aniline system. The pseudo-second-order model was found to be better (R2> 0.986) than the others. Based on the Weber & Morris models, the intra-particle-diffusion rate was considered to be the rate-limiting step for aniline adsorption in the first 10 min, and then, the adsorption rate was found to be limited by two or more diffusion steps. The isotherm data showed that the system conformed to the Langmuir model.The efficiency of the WFBAC was compared with that of CAC in this study. The effect of the contact time, dosage and temperature on the removal of CODcr and TOC from dyeing wastewater was investigated. The kinetics of the CODcr removal was also conducted. The removal rates of CODcr and TOC was 77% and 74% at the optimal conditions (contact time:2 h, dosage:1. Og/L, temperature:30℃) when used the WFBAC. The removal rate of CODcr using WFBAC was 24.19% higher than that using CAC. The kinetic data was found to more conform to the pseudo-second-order (R2> 0.99).The adsorption velocity was controlled by the intra-particle diffusion at the first 30min, then the adsorption velocity was dominated by the diffusion in the film as well as the intra-particle diffusion.