常压DBD等离子体法气相苯加氢反应的研究

采用CTP-2000 K等离子体电源,对常压介质阻挡放电等离子体下气相苯催化加氢反应进行了研究.在无催化剂条件下,考察了放电电压,停留时间,气体物料配比对苯加氢反应的影响,并优化出等离子体法的反应条件:气体停留时间12 s,物料配比VH2/VAr+Ben=2:1,放电电压14 kV.在此条件下,对催化剂用于等离子体苯加氢反应的催化活性进行了考察,实验结果表明用浸渍法制备的金属催化剂可使苯的转化率从无催化剂时的78%提高到90%以上,目标产物环己烷和环己烯的总收率可达到70%以上.运用BHJ和EMS技术对自制催化剂的结构性能进行了表征,结果表明在常压常温用等离子体进行还原处理的催化剂,其比表面积从13.72 m2/g提高到19.08 m2/g,孔体积由76.81×10-3cm3/g提高到107.7×10-3cm3/g.用扫描电镜分析了所制备催化剂的表面特征,催化剂活性组分在载体表面分布均匀,表面颗粒粒度为8 nm左右,Ni元素在外表面的质量分数达到32%.

Study on Benzene Hydrogenation Reaction Process by DBD Plasma at Atmospheric Pressure

DBD(Dielectric Barrier Discharge)plasma was used to study the hydrogenation reaction of benzene by the CTP-2000K plasma power supply at atmospheric pressure.The discharge voltage,residence time and proportion of gas material were changed respectively to establish the optimized conditions.The optimized conditons were found to be discharge voltage14 kV,residence time 12s,gas ratio of VH2/VAr=2∶ 1.The effect of plasma-catalytic synergy on the raction was investigated.Compared with the result of non-existent catalyst,the percent conversion of benzene increased from 78% to greater than 90%,and the selectivity of cyclohexane could reach 70%.The prepared catalyst was characterized by BHJ and EMS,respectively.The results indicate that the catalyst handled by plasma,the specific surface area increased from 13.72 m2·g-1 to 19.08 m2·g-1,and the hole volume increased from 76.81×10-3cm3·g-1 to 107.7×10-3cm3·g-1,respectively.SEM analysis shows the the surface grain size distribution on Ni/SiO2 catalyst is uniform for 8 nm,the action element Ni of catalyst is up to 32% at outside surface