文献类型：期刊文献

英文题名：Solvation of hydrocarbon radicals in sub-CW and SCW: An ab initio MD study

作者：Yuan, Pei-Qing[1]; Zhu, Chun-Chun[1]; Liu, Ying[1]; Bai, Fan[1]; Cheng, Zhen-Min[1]; Yuan, Wei-Kang[1]

机构：[1] State Key Laboratory of Chemical Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China

年份：2011

卷号：58

期号：1

起止页码：93

外文期刊名：Journal of Supercritical Fluids

收录：EI(收录号：20112814129899)

语种：英文

外文关键词：Phase equilibria - Cracking (chemical) - Hydrocarbons - Calculations - Molecules

摘要：Solvation of methyl radicals in subcritical and supercritical water was investigated with the ab initio MD simulation to increase the understanding of the thermal cracking of hydrocarbons under the severe hydrothermal environments. The calculation results show that water clusters around the radical could be formed with the following prerequisites: the bulk density of water is close to liquid phase, and the state point of water on its phase diagram is far away from the critical point and from the vapor-liquid equilibrium boundary. The occurrence of water clusters superimposes a negative influence on the originally depressed diffusivity of the radical under the dense hydrothermal environments, and the interference from the immediately adjacent water molecules with the frontier orbitals of the radical results in randomly reduced activity of the radical. Regardless of whether there are water clusters around the radical or not, in subcritical and supercritical water the bimolecular reactions participating via hydrocarbon radicals should be partially suppressed by the reduced diffusivity and lower activity of the radical. ? 2011 Elsevier B.V. All rights reserved.