点击次数：

论文类型： 期刊论文

发表时间： 2017-04-01

发表刊物： CHEMICAL ENGINEERING JOURNAL

收录刊物： SCIE、EI

卷号： 313

页面范围： 37-46

ISSN号： 1385-8947

关键字： Plasma chemistry; Hydrogen peroxide; Direct synthesis; Selectivity control; Electron density; Average electron energy

摘要： Low selectivity is one of the key problems which limit the application of plasma in chemical fields. High selectivity and concentration of H2O2 are critical in the direct synthesis of H2O2. Herein, we report that the selectivity of the H-2/O-2 plasma reaction can be controlled by specific energy input (SEI), i.e. low SEI leads to high H2O2 selectivity. When the SEI was fixed at 2.08 j/ml, the H2O2 selectivity reached 91% with 17% O-2 conversion, and a H2O2 solution with high concentration (90 wt.%) was achieved. Plasma diagnostics and theoretical calculation results indicate that, low SEI results in low electron density, which leads to high H2O2 selectivity but low O-2 conversion. FurtherMore, the collision cross sections of H-2 and O-2 molecules with electrons indicate that the H-2/O-2 plasma, with average electron energy of 11.5 eV, can synthesize H2O2 with high selectivity and high O-2 conversidn. (C) 2016 Elsevier B.V. All rights reserved.