一步快速活化法制备生物质活性炭及其对乙酸乙酯的吸附再生

Preparation of biomass activated carbon by one step rapid activation and its adsorption regeneration for ethyl acetate

活性炭吸附法因技术成熟、简单易行、吸附效率高等优点而被广泛应用于挥发性有机化合物(VOCs)的处理中。本文以山林废弃物的野山桃核为原料,烟道废气及硝酸铁为活化剂,制备了一系列生物质活性炭,并利用固定床吸附装置对其吸附、再生性能进行了研究。利用二氧化碳和水蒸气模拟烟气,在固定流量的烟气活化氛围中进行活化,并探讨了不同硝酸铁的量对活性炭的孔隙结构及其吸附再生性能的影响。利用N2吸附-脱附实验、扫描电镜、拉曼光谱和红外光谱等技术研究了活性炭详细特征。结果表明:当硝酸铁的质量分数为0.2%时,所制备的活性炭AC-3具有最大的比表面积和平均孔径,分别为923m^(2)/g及2.57nm。其对乙酸乙酯的饱和吸附量也最大,为973.04mg/g。利用烟气对AC-3活性炭进行活化再生处理,经过3次重复吸附-解吸再生实验,其饱和吸附能力仍可达91.5%以上,实现了废弃烟气资源化利用及活性炭的循环回收,从而达到废气治理的目标。

Volatile organic compounds(VOCs)are important precursors of photochemical smog,which have a great impact on the formation of tropospheric ozone and secondary fine particle pollutants,and are the focus of current atmospheric environmental pollution research.At present,activated carbon adsorption method is widely used in the treatment of VOCs because of its mature technology,simple operation and high adsorption efficiency.In this paper,a series of activated carbons were prepared from wild hickory as raw materials,flue gas and ferric nitrate as activators,and their adsorption and regeneration properties were studied by fixed bed adsorption device.Carbon dioxide and water vapor were used to simulate flue gas and activated in a fixed flow flue gas activation atmosphere. The effects of carbon dioxide and watervapor in flue gas and different amounts of ferric nitrate on pore structure and adsorption regenerationperformance of activated carbon were discussed. The detailed characteristics of activated carbon werestudied by N2 adsorption desorption experiment, SEM, Raman and FTIR. The results show that when themass fraction of ferric nitrate is 0.2%, the AC-3 has the largest specific surface area and average porevolume, which are 923m^(2)/g and 2.57nm, respectively. Its saturated adsorption capacity for VOCs ethylacetate was 973.04mg/g. In this experiment, AC-3 activated carbon was activated and regenerated by fluegas. After three repeated adsorption desorption regeneration experiments, the saturated adsorptioncapacity of AC-3 activated carbon was still above 91.5%. The waste flue gas resource utilization andactivated carbon recycling were realized, so as to achieve the goal of waste gas pollution adsorptiontreatment.