RuO_2/Ti阳极电化学氧化吸收氨废气  

Removal of ammonia by absorption combined with electrochemical oxidation on RuO_2/Ti anode

作　　者：徐晓华[1] 许青枝 黄桂凤[1] 王莉莉[1] 黄立维[1] 

机构地区：[1]浙江工业大学环境学院,浙江杭州310014

出　　处：《化工学报》2016年第6期2568-2574,共7页CIESC Journal

摘　　要：采用溶液吸收结合电化学氧化法处理氨废气。电化学反应器采用尺寸为φ35 mm×350 mm的管式玻璃反应器,内壁贴附不锈钢网作为阴极,反应器中心轴向设置有φ10 mm×350 mm的钌钛电极(RuO_2/Ti)棒作为阳极。电极浸没在吸收液中,含氨气体从反应器底部经气体分布器导入反应器。实验结果表明,与溶液吸收相比,溶液吸收结合电化学氧化可以更长时间保持较高的氨气去除率。由于RuO_2/Ti电极产生的有效氯的间接氧化作用,氨气在NaCl溶液比在Na_2SO_4溶液中的去除率更高。以NaCl为电解液时,酸性条件下更有利于氨气的吸收和降解,并且氨气的去除率随着电流密度的增加而增加。产物分析发现氨气在NaCl和Na_2SO_4溶液中被电化学氧化后,主要产物为氮气,也有少量氨转化为硝酸根离子。Ammonia in the exhaust gas was treated by solution absorption combined with electrochemical oxidation. The electrochemical reactor was a tubular glass reactor（φ35 mm×350 mm） with a stainless steel mesh attached to the inner wall as the cathode, and a titanium rod（φ10 mm×350 mm） coated with RuO_2（RuO_2/Ti） fixed on the axis of the reactor as the anode. Electrodes were immersed in absorption solutions. The sample gas containing ammonia was introduced to the reactor by a gas distributor installed at the bottom of the reactor. Experimental results indicated that the removal of ammonia was higher by absorption combined with electrochemical oxidation compared with solution absorption only. The removal of ammonia is higher in Na Cl solution than that in Na_2SO_4 one, which was attributed to the indirect oxidation of active chlorine generated by electrochemical reaction on RuO_2/Ti anode. It was confirmed that oxidation of ammonia increased with low p H of Na Cl solutions. With the increase of current density applied to the reactor, the decomposition of ammonia also increased. The major of absorbed ammonia in Na Cl and Na_2SO_4 solution converted to nitrogen after electrochemical reaction. Only a small amount of nitrate was found in solutions after reaction.

关 键 词：RuO2/Ti阳极 电化学 溶液 吸收 氨 废气 

分 类 号：X512[环境科学与工程—环境工程]