超声浸渍法、溶胶凝胶法制备高温煤气脱硫剂

发布时间：2019-06-10 21:14

【摘要】：采用普通浸渍法、超声浸渍法和溶胶凝胶法三种方式制备高温煤气脱硫剂,通过ICP、SEM、XRD、氮吸附等手段对脱硫剂进行表征,并在一立式固定床上进行活性评价。得出结论如下： (1)采用超声浸渍法和普通浸渍法制备铁、锰、铜、锌、铈、钙六种物系脱硫剂,ICP-AES结果表明超声浸渍不仅缩短了浸渍时间,还促进了活性成分的负载。BET分析结果和粒径分布曲线表明,超声浸渍丰富了脱硫剂的孔隙结构,增加了比表面积和孔容,并具有细化颗粒的效果。SEM结果显示,超声浸渍制备得到的脱硫剂颗粒较小而且分布均匀,烧结程度较轻。XRD分析表明超声浸渍对脱硫剂的晶粒分布状态有影响。在固定床上对所有脱硫剂进行活性评价,结果表明超声波浸渍法制备得到的脱硫剂的穿透硫容有显著提高。6种物系的脱硫穿透硫容比较结果为：MnFeCuCeCaZn,但超声波处理后Fe的穿透硫容提高最为明显。 (2)采用超声浸渍法分别制备Mn/SiO2、Mn/TiO2、Mn/γ-Al2O3三种高温煤气脱硫剂,研究载体对于脱硫剂活性的影响。三种载体的比较研究表明,Mn/γ-Al2O3比表面积大,脱硫活性大,能满足IGCC中硫化氢的净化要求,是一种较好的高温煤气脱硫剂。而Mn/SiO2不能较长时间维持硫化氢在低浓度,Mn/TiO2高温稳定性差。 (3)采用溶胶凝胶法和超声浸渍法分别制备相同负载的锰系脱硫剂,并对其进行表征和活性评价,得出结论：溶胶凝胶法制备得到的脱硫剂孔隙更为丰富,具有良好的微观结构,XRD测试结果显示其活性成分在载体上的分布更为均匀,能够更好的进行脱硫反应。溶胶凝胶法制备得到的脱硫剂活性比相同负载下的超声浸渍法制得的脱硫剂来得高。温度越大,脱硫剂活性增大,但是涨幅并不大。总体上讲,溶胶法具有较为优良的性能,各种参数比超声浸渍来得好；但是,由于其制备工艺较为复杂,费用高,目前难以在工业化推广应用。
[Abstract]:High temperature gas desulphurizer was prepared by ordinary impregnation method, ultrasonic impregnation method and sol-gel method. The desulphurizer was characterized by ICP,SEM,XRD, nitrogen adsorption and evaluated in a vertical fixed bed. The conclusions are as follows: (1) six kinds of desulphurizing agents, iron, manganese, copper, zinc, cerium and calcium, were prepared by ultrasonic impregnation and ordinary impregnation. ICP-AES results show that ultrasonic impregnation not only shortens the impregnation time. The results of BET analysis and particle size distribution show that ultrasonic impregnation enriches the pore structure of desulphurizer, increases the specific surface area and pore volume, and has the effect of refining particles. SEM results show that the ultrasonic impregnation enriches the pore structure of desulphurizer, increases the specific surface area and pore volume, and has the effect of refining particles. The particles of desulphurizer prepared by ultrasonic impregnation are small and uniform, and the sintering degree is light. XRD analysis shows that ultrasonic impregnation has an effect on the grain distribution of desulphurizer. The activity of all desulphurizers was evaluated in a fixed bed. The results showed that the penetrating sulfur capacity of the desulphurizers prepared by ultrasonic impregnation method was significantly improved. The comparison of desulphurization penetrating sulfur capacity of six kinds of compounds was as follows: MnFeCuCeCaZn, However, the penetrating sulfur capacity of Fe increased most obviously after ultrasonic treatment. (2) three kinds of high temperature gas desulphurizer Mn/SiO2,Mn/TiO2,Mn/ 纬-Al2O3 were prepared by ultrasonic immersion method, and the effect of carrier on the activity of desulphurizer was studied. The comparative study of the three carriers shows that Mn/ 纬-Al2O3 has large specific surface area and high desulphurization activity, which can meet the purification requirements of hydrogen sulfide in IGCC and is a good high temperature gas desulphurizer. However, Mn/SiO2 can not maintain hydrogen sulfide at low concentration for a long time, and the high temperature stability of Mn/TiO2 is poor. (3) Manganese desulphurizer with the same load was prepared by sol-gel method and ultrasonic impregnation method, and its characterization and activity evaluation were carried out respectively. it was concluded that the pores of desulphurizer prepared by sol-gel method were more abundant. The results of XRD test show that the distribution of active components on the carrier is more uniform and the desulphurization reaction can be carried out better. The activity of desulphurizer prepared by sol-gel method is higher than that prepared by ultrasonic impregnation under the same load. The higher the temperature, the higher the activity of desulphurizer, but the increase is not great. Generally speaking, the sol method has excellent properties and various parameters are better than those of ultrasonic impregnation. However, because of its complex preparation process and high cost, it is difficult to be popularized and applied in industrialization at present.
【学位授予单位】：浙江大学
【学位级别】：硕士
【学位授予年份】：2010
【分类号】：X701.3

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