LaNi_(5)合金中的杂质C与H_(2)的反应研究  

Reaction of Impurity C in LaNi_(5) Alloy with H_(2)

作　　者：王宏博 王树茂 武媛方 郭秀梅 李志念 Wang Hongbo;Wang Shumao;Wu Yuanfang;Guo Xiumei;Li Zhinian(National Engineering Research Center of Nonferrous Metals Materials and Products for New Energy,GRINM Group Co.,Ltd.,Beijing 100088,China;GRIMAT Engineering Institute Co.,Ltd.,Beijing 101407,China)

机构地区：[1]有研科技集团有限公司国家有色金属新能源材料与制品工程技术研究中心,北京100088 [2]有研工程技术研究院有限公司,北京101407

出　　处：《稀有金属》2023年第4期587-593,共7页Chinese Journal of Rare Metals

基　　金：科技部国家重点研发计划项目(2018YFB1502105,2017YFE0301505)资助。

摘　　要：LaNi_(5)储氢合金中的杂质C在合金放氢过程中尤其是在高温放氢时会以CH_(4)的形式释放,从而影响氢气的纯度。氢等离子体电弧熔炼法是去除LaNi_(5)合金中杂质C的有效方法,其中H在除C过程中起到了至关重要的作用。为了研究C与H_(2)在氢等离子体电弧熔炼过程中的作用机制,本文利用气相色谱分析仪分别对熔炼前后的炉内气氛进行了分析研究。此外,依据LaNi_(5)合金与H的相互作用,本文探索了吸氢脱氢过程中,合金中杂质C与H的反应过程,并对合金高温放氢纯度及放氢后合金C含量的变化进行分析。结果表明:在氢等离子体电弧熔炼和吸氢脱氢处理过程中,LaNi_(5)合金中的C与H反应并以CH_(4)的形式逸出,从而降低了LaNi_(5)合金中的C含量。在对LaNi_(5)合金吸氢脱氢法处理过程中,合金中的原始C含量越高,500℃热解析H_(2)中的CH_(4)含量越高,且随着吸放氢循环次数的增加,释放的CH_(4)含量降低。吸氢脱氢处理可以作为去除LaNi_(5)储氢合金杂质C的有效方法,吸氢量对吸放氢前后合金中C含量的变化无显著影响,处理温度升高以及处理时间的延长有利于合金中C的去除。Hydrogen energy was considered to be the best substitute for fossil energy.LaNi_(5) alloy was an early and mature hydrogen storage alloy.It was easy to activate,had a fast hydrogen absorption and desorption rate,could release hydrogen at room temperature,and had high discharge performance.Therefore,it had been widely used in the fields of solid-state hydrogen storage and transporta⁃tion,hydrogen isotope storage,and nickel-hydrogen batteries.It was known that in the application of LaNi_(5) hydrogen storage alloy,im⁃purity C would be precipitated in the form of hydrocarbons,especially in the form of CH_(4) when hydrogen was released at high tempera⁃ture,thereby polluting hydrogen and affecting the subsequent application of hydrogen.Therefore,it was necessary to study a method to reduce the impurity C content in LaNi_(5) hydrogen storage alloy,and to explore the principle or mechanism.Experiments found that met⁃al La and Ni,with high original C impurity content,could reduce the overall C impurity content of the melted alloy by plasma arc melt⁃ing.When hydrogen plasma was used for melting,C impurity content would be further reduced.The effectiveness of reducing the impu⁃rity content was limited by a certain limit.After a certain number of cycles of hydrogen storage in LaNi_(5) hydrogen storage alloy,the im⁃purity C content of the alloy showed a decreasing trend,and H plaied a crucial role in the process of C removal.In order to study the action mechanism of C and H_(2) in the process of hydrogen plasma arc melting,this paper used a hydrogen plasma arc furnace for alloy melting,pressure-composition-temperature(PCT)test bench for hydrogen absorption,discharge and storage cycles,and a gas chro⁃matographic analyzer for the furnace atmosphere before and after melting.Analytical studies were carried out.In addition,according to the interaction between LaNi_(5) alloy and H,this paper explored the reaction process of impurities C and H in the alloy in the process of hydrogen absorption and dehydrogenation,and

关 键 词：LaNi_(5)合金 氢等离子体电弧熔炼法 吸氢脱氢法 杂质C含量 

分 类 号：TF805.1[冶金工程—有色金属冶金]