Study On CO₂ Adsorption And Desorption Of Waste Ion-exchange Resin Activated Carbon

With the development of global industrial modernization,the problem of excessive CO2 emissions has drawn wide attention from domestic and foreign scholars,CO2 adsorption separation and recovery technology has received widespread attention.The main source of CO2 emission in our country is coal-fired power plant,therefore,the capture and recovery of CO2 in power plant flue gas is an important means to reduce CO2 emissions.CO2 in power plant flue gas is low in partial pressure and low in content,in view of this feature,we select the adsorption method for capture.Adsorption technology is a low energy regeneration,adsorption capacity,selectivity,easy to control,recyclable carbon dioxide separation technology.The key is the selection of adsorbent material and preparation and adsorption equipment design.Resin,a polymer compound widely used in chemical industry,medicine and aviation,produces 500 thousand tons of waste resin every year,which is about 160 thousand tons in China every year.Waste resin is not easy to degrade,long-term accumulation will harm the environment.Therefore,we use the waste resin as the raw material to prepare the activated carbon,which is mainly of two significance--energy saving and environmental protection.In this paper,activated carbon was prepared from the waste ion exchange resin,and the adsorption and desorption properties of carbon dioxide were studied.(1)The resin based activated carbon was prepared by using waste resin as raw material and its physical properties were analyzed,it was found that the resin activated carbon has a large specific surface area.This shows that activated carbon is a very attractive adsorbent for industrial adsorption of CO2.(2)Through the resin-based activated carbon adsorption of CO2,the study found:With the increase of CO2 concentration,the breakthrough time of resin-based activated carbon decreases and the CO2 adsorption capacity increases;With the increase of inlet velocity,the penetration time decreases and the CO2 adsorption capacity decreases;With the increase of the amount of activated carbon,the penetration time increases and the amount of CO2 adsorbed slightly decreases;With the adsorption temperature increases,the breakthrough time decreases and the amount of CO2 adsorbed decreases.(3)Through the experimental study of CO2 desorption of activated carbon:In the process of desorption,with the increase of the desorption temperature,the concentration of CO2 in the product gas increases and the desorption time increases;With the increase of CO2 concentration,the concentration of CO2 in the product gas increases and the desorption time also increases.And,under the selected desorption conditions,the activated carbon can fully regenerated.(4)Through the flue gas impurities in the experiment,the study found:The presence of trace amounts of SO2 in the impurities reduces the amount of CO2 adsorbed by the resin-based activated carbon and has little effect on the regeneration performance of activated carbon.The presence of trace amounts of NO has almost no effect on the CO2 adsorption on resin-based activated carbon and can be neglected.The presence of trace H2O will reduce the breakthrough time of resin-based activated carbon CO2 and reduce the adsorption capacity.When all three impurities are present,after 10 cycles of adsorption,it is found that the presence of impurities reduces the amount of CO2 adsorbed,but the cycle performance of the activated carbon is not affected.