【作者】 艾莹莹；

【导师】 张永春；

【作者基本信息】 大连理工大学 ， 工业催化， 2010， 硕士

【摘要】 二氧化碳是造成温室效应的主要气体之一,但工业排放的二氧化碳大部分没有充分地回收,这既加快了温室效应的速度,又浪费了大量的二氧化碳资源。因此二氧化碳的回收再资源化具有重要的科学意义和应用价值。本文针对回收氮气中低浓度二氧化碳,采用常压固定床动态吸附装置,致力于开发出高效二氧化碳吸附剂,以达到充分回收二氧化碳的目的。论文的实验内容包括：一、分子筛吸附二氧化碳的研究：考察了多种分子筛吸附剂对二氧化碳的吸附性能。详细考察了气体流量、吸附温度、床层高度及预处理等吸附条件对穿透曲线、吸附量的影响。实验结果表明：5A分子筛经铝溶胶粘合剂加工成条形后对CO2的吸附性能最佳。适当增加床层高度、低温操作都有利于对CO2的吸附,但增大入口气流速不利于分子筛对CO2的吸附。对条形5A分子筛进行300℃下加热3h预处理,可以提高其对CO2的吸附速率；氮气载水预处理会造成其孔道的堵塞而导致CO2吸附容量下降。二、改性条形5A分子筛对二氧化碳的吸附研究：对条形5A分子筛进行负载金属离子改性处理,详细考察了金属浸渍剂种类、浓度等因素对条形5A分子筛吸附CO2性能的影响。实验结果表面：过渡金属离子Mn4+、Cr3+、Cu2+改性条形5A分子筛均不能提高二氧化碳的吸附量。三、对条形5A分子筛再生后性能的研究：考察了5A分子筛经多次循环使用的再生性能,并对其进行热重分析,发现条形5A分子筛除对CO：具有较高吸附量外,还能与CO2形成较强的吸附作用,需较高温度才能完全脱除。实验结果表明：重复使用6次,5A分子筛对CO2吸附容量无明显下降；加热再生法对5A分子筛有较好的再生效果,再生时间为180min时,5A分子筛在300℃下基本完成再生。四、介孔分子筛SBA-15的二氧化碳吸附性能的研究：实验选用SBA-15介孔分子筛为载体,以PEI对其进行氨基修饰,考察了浸渍剂浓度、吸附温度对二氧化碳吸附性能的影响。并对其进行XRD、FTIR和热重分析。实验结果表明PEI在介孔分子筛中的最佳配比为wt50%,最佳吸附温度为48℃。最后考察了PEI/SBA-15的再生性能。结果表明：SBA-15-PEI-50的再生条件较为简单,在100℃下,以100mL/min的流量通入高纯N2即可脱附。更多还原

【Abstract】 CO2 is one of the main greenhouse gases, but the majority of industrial output of CO2 without adequate recovery, which not only accelerate the pace of the greenhouse effect, but also waste a lot of carbon resources. So best utilization of CO2 recycling is important for scientific significance and application value. The purpose of this study is to develop efficient adsorbens for low-concentration CO2 removal from N2 steam using fixed-bed reactor. The contents of the job are listed as follows:1. The investigation of molecular sieve of CO2 adsorption. The adsorption capacity of different types of adsorbents has been investigated. The effect of the gas flow rate, adsorption temperature, bed height and pretreatment on the adsorption breakthrough curve, adsorption capaeity are investigated. Results show that 5A molecular sieve which is molded by aluminum sol binder has the best adsorption properties of CO2. Appropriately increasing bed thickness and low temperature operation are both conducive to the absorption of CO2. But the increased flow rate is not conducive to the absorption of CO2. The CO2 adsorption rate increases while using 5A molecular sieve heated at 300℃for 3h. Pretreatment of nitrogen containing water will cause the pore blockage of 5A molecular sieve which lead to the decrease of CO2 adsorption capacity.2. The study on the modified 5 A molecular sieve of CO2 adsorption.5 A molecular sieve is treated by metal ions modifieation. Some factors which may affect the adsorption capacity such as the species and the concentration of metal salts are also investigated in the fixed-bed reactor. Results show that Cu4+, Mn3+, Cr2+ modification can cause the decline of the CO2 absorption capacity.3. The investigation of the regeneration of 5A molecular sieve. From theTG results, we find that 5A molecular sieves are good adsorbents with high capacity as well as strong bonding with CO2. Results also show that after recycling of 5A molecular sieve for 6 times, its CO2 adsorption capacity does not decrease significantly.5A molecular sieve has effective adsorption performance after heating regeneration for 180min at 300℃.4. The study on CO2 absorption capacity with SBA-15 mesoporous molecular sieve. SBA-15 mesoporous molecular sieve is used as support, then PEI amino modification is investigated. The concentration of PEI as well as modification temperature are studied as the factor of CO2 absorption capacity. XRD and TG results are analyzed. Results show that the best ratio of PEI is wt50%, the optimum temperature is 48℃. Finally, the regeneration of SBA-15-PEI-50 is investigated. Results show that its regeneration condition is simple, SBA-15-PEI-50 can be regenerated at 100℃with N2 flow rate of 100mL/min.更多还原