为了实现烟气CO2的低成本、高效捕集,研究负载1,8-二氮杂二环[5,4,0]十一碳-7-烯(1,8-diazabicyclo[5,4,0]undec-7-ene,DBU)的颗粒活性炭(granular activated carbon,GAC)吸附剂对CO2捕集性能。DBU负载率越高,吸附剂比表面积、总孔容积和微孔容积越小,平均孔径与负载率呈明显的负相关性;Langrnuir模型是拟合DBU在GAC上吸附行为拟合优度最佳的模型,DBU在GAC上单分子层吸附要多于多分子层吸附;DBU-GAC吸附剂在低于140℃时具有良好的热稳定性,DBU能抑制吸附剂水分蒸发,有利于DBU与CO2耗水反应;DBU溶液对CO2具有很高的捕集效率,是常用-乙醇胺-甲基二乙醇胺(monoethanolamine-methyl—diethanolamine,MEA-MDEA)复合胺溶液的2.6~3。3倍;GAC负载适量DBU对模拟烟气CO2具有良好的捕集效率,消除膜封效应能提高DBU-GAC吸附剂对CO2的吸附容量。
The performance of 1,8-diazabicyclo [5,4,0]undec-7-ene (DBU) loaded on granular activated carbon (GAC) was preliminary researched to realize CO2 capture in flue gas with low cost and high efficiency. The higher the DBU load rate, its surface area, total pore volume and pore volume become smaller while the average pore size is negatively correlated to DBU load rate. The model obtained that the best of goodness of fit about the DBU adsorption on GAC is the Langmuir model, and the mono-molecular layer adsorption of DBU on GAC is greater than the multi-molecular layer adsorption. DBU-GAC adsorbent has a good thermal stability below 140~C, and DBU can effectively keep the water on the adsorbent from evaporating which is benefit to the reaction of DBU, H20, and CO2. The DBU solution performs high absorption efficiency to CO2, and its absorption capacity is about 2.6-3.3 times to monoethanolamine-methyldiethano- lamine (MEA-MDEA) solution. DBU-GAC adsorbent with an appropriate DBU load rate has a good effect on the adsorption of CO2 in simulated flue gas, and the film sealing effect of DBU on GAC must be eliminated to improve the adsorption capacity of adsorbent