摘要
为研究砷铁渣中化合物真空下热分解的机理,对砷铁渣中FeAs、FeAs2进行真空条件下热分解的热力学计算,得到它们在1463 K,30 Pa的条件下可能发生的分解反应。采用基于密度泛函理论的平面波赝势法计算得到FeAs和FeAs2的稳定结构。并用从头算分子动力学的方法模拟了它们在1463 K,30 Pa的条件下的热分解过程。采用B3LYP杂化泛函计算了As2、As3、As4分子的稳定结构,并用二次同步转变的方法计算了气态As分子之间反应的过渡态。计算结果表明,在模拟条件下砷的脱除可能分步进行,并且更倾向于以As2的形式分离出去。
The removal of arsenic from arsenic-iron compounds, FeAs and FeAs2 in the slag generated in industrial smelting of tin-ore, by vacuum thermal decomposition was modeled, calculated in molecular dynamics, and simulated in density functional theory （DFT） with CASTEP code of Material Studio. The calculated results show that the thermal de- composition occurs at 1463 K and 30 Pa. The stable lattice structures of bulk FeAs and FeAs2, as well as As2, As3, and As4 molecular structures were evaluated. Moreover, the transition state between gaseous arsenic molecules was investigated in quadratic synchronous transit method. The simulated results show that the arsenic gas molecule with even number of As atom is more stable than that with odd number of As atom. We concluded that As can be partly removed from the slag by vacuum decomposition under the simulated conditions, possibly in the form of As2.
出处
《真空科学与技术学报》
EI
CAS
CSCD
北大核心
2014年第10期1128-1134,共7页
Chinese Journal of Vacuum Science and Technology
基金
NSFC-云南联合基金项目(U1202271)
国家基金青年基金项目(51104078)
昆明理工大学人才培养基金项目(KKZ3201252020)
云南省自然科学基金项目(2010CD022)
教育部高校科研创新团队计划(IRT1250)
关键词
从头算分子动力学
FeAs
FeAs2
晶体结构
热分解
砷分子
Ab initio molecular dynamics, FeAs and FeAs2, Crystal structures, Themlal decomposition, Arsenic molecules
