The Application And Research Of Activated Carbon In Coordination With Microwave Oxidizing Reactive Red X-3B And Modification

According to the characteristics and the existing problems in the research of the dyeing wastewater, the feasibility of microwave in coordination with activated carbon oxidizing dyeing wastewater was analyzed in this paper. Microwave in coordination with activated carbon oxidation technology is characterized by fast reaction velocity, small floor space, simple equipment, easy operation and so on. It has a broad prospect for application in dyeing wastewater treatment. According to the high using cost of activated carbon in coordination with microwave oxidation process, the several kinds of activated carbons were optimized and a kind of high efficient and economical load-modified activated carbon was prepared in this paper. Then the microwave in coordination with activated carbon oxidizing reactive red X-3B process and microwave in coordination with modified activated carbon oxidizing reactive red X-3B process were optimized by using reactive red X-3B as model dyeing wastewater. The kinetics and mechanism of reactive red X-3B in the microwave in coordination with activated carbon oxidation process were studied. The reasons of activated carbon inactivation and modified activated carbon inactivation in the use were investigated. And the technology of microwave radiation regeneration was used to regenerate the inactivated modified activated carbon.First of all, through the comparison of price, adsorption performance, cost-efficiency of several different activated carbons, the honeycomb activated carbon was chosen for the research of disposing reactive red X-3B in the paper.100ml dyeing wastewater containing100mg/L reactive red X-3B was treated in the microwave in coordination with activated carbon oxidation process and98.2%of reactive red X-3B and92.4%of TOC could be removed under the optimum process condition:microwave power700W, irradiation time3min, pH1.8, activated carbon dosage50g/L Reaction kinetics in the microwave in coordination with activated carbon oxidation process, traditional waterbath process and activated carbon adsorption alone were studied as well. The results suggested that the processes were first-order reaction for reactive red X-3B. Moreover, comparison of the removal percentage of reactive red X-3B, it could be concluded that microwave irradiation and activated carbon work together to improve the removal rate of reactive red X-3B. Through the discussion about the effects on the following three areas:synergism between microwave and activated carbon, effects of H+, degradation mechanism of" microwave hot spots", it showed that the result of disposing the reactive red X-3B by microwave in coordination with activated carbon was a complex combination of the results of disposing by activated carbon and microwave alone, and the existence of H4could not promote inducing hydroxyl radicals and "microwave hot spots", but could promote the adsorption of activated carbon.Then, ultrasonic impregnation method was used to prepare load-modified activated carbon in the article, and the microwave in coordination with modified activated carbon oxidizing reactive red X-3B process was optimized.100ml dyeing wastewater containing100mg/L reactive red X-3B was treated in the microwave in coordination with modified activated carbon oxidation process and99%of reactive red X-3B could be removed under the optimum process condition:microwave power 560W, irradiation time1.5min, pH1.8, modified activated carbon dosage30g/L. Compared with microwave in coordination with activated carbon oxidation process, the process was second-order reaction for reactive red X-3B and the shortcomings as excessive dosage of activated carbon and long time of microwave irradiation were solved.Finally, the problem of deactivation and regeneration of activated carbon in the reactive red X-3B treatment process was also studied in the article. Through the analysis of BET and SEM, the results indicated that the inactivation of activated carbon was mainly due to the adsorption pore of activated carbon was blocked by sediments, while in addition to the loss of active ingredients, the main reason for the deactivation of modified activated carbon was the sediments remai ned on the surface of modified activated carbon and covered the active sites. Microwave radiation is a regeneration method with short regeneration time, simple operation, and high security. The regenerated modified activated carbon could restore the high activity of the fresh with the following working conditions:power of microwave,420W, exposure time,1min, SiC activated carbon ratio,2:1. Under this condition, the regenerated activated carbon and modified activated carbon still had a long lifespan.In this paper, an efficient, economical and long-life activated carbon was found by optimizing and modifying. And the process of adsorption of activated carbon was associated with the microwave technology, which would provide theoretical references for the process using in the actual dyeing wastewater treatment in the future.