纳秒脉冲介质阻挡放电等离子体合成氨工艺条件优化  

Optimization of Process Parameters for Ammonia Synthesis by Nanosecond Pulsed Dielectric Barrier Discharge Plasma

作　　者：刘洋[1] 张海宝[1] 陈强[1] LIU Yang;ZHANG Hai-Bao;CHEN Qiang(Laboratory of Plasma Physics and Materials,Beijing Institute of Graphic Communication,Beijing 102600,China)

机构地区：[1]北京印刷学院等离子体物理与材料实验室,北京102600

出　　处：《应用化学》2023年第2期268-276,共9页Chinese Journal of Applied Chemistry

基　　金：国家自然科学基金(No.11875090);北京市自然科学基金(No.1192008);北京市教委项目(No.KM202010015003)资助。

摘　　要：氨(NH3)作为重要的化工原料对农业及国计民生发展有直接影响。工业合成氨需高温高压、能耗高和污染重。低温等离子体技术是一种可持续,有潜力的合成氨途径,已成为国内外研究热点。本工作以氮气和氢气为原料,在低温常压下采用纳秒脉冲介质阻挡放电等离子体合成氨,通过单因素实验系统研究脉冲峰值电压、脉冲重复频率、气体总流量、N_(2)和H_(2)体积比(V(N_(2))∶V(H_(2)))等因素对合成氨速率及能量产率的影响规律。进一步通过正交实验评价确定影响合成氨反应速率因素的主次顺序为:脉冲峰值电压>脉冲重复频率>气体体积比>气体总流量。影响合成氨能量产率因素的主次顺序为:脉冲峰值电压>气体体积比>脉冲重复频率>气体总流量。结合两部分实验,最终得到合成氨的优选条件:脉冲峰值电压16 kV、脉冲重复频率6 kHz、脉冲上升沿100 ns、V(N_(2))∶V(H_(2))=1∶1、气体总流量200 mL/min。此时NH3合成速率最高为923.08μmol/h,能量产率为0.30 g/kWh。Ammonia(NH3)as an important chemical raw material has a direct influence on the development of agriculture,national economy and people’s livelihood.It is a high temperature,high pressure,high energy consumption and heavy pollution process in the industrial synthesis of ammonia.Low-temperature plasma technology is a sustainable and promising technology for ammonia synthesis,which has become a research hotspot at home and abroad.In this work,nitrogen and hydrogen are used as raw materials,and nanosecond pulsed dielectric barrier discharge is used to synthesize ammonia at low temperature and atmospheric pressure.The effects of factors such as pulse peak voltage,pulse repetition frequency,total gas flow rate,and N_(2)∶H_(2)volume ratio on the synthesis rate and energy yield of ammonia synthesis are investigated systematically through a single-factor experiment.Furthermore,through the orthogonal experimental evaluation,it is determined that the order of factors affecting the synthesis rate is:pulse peak voltage>pulse repetition frequency>gas volume ratio>gas total flow rate.The order of factors affecting the energy yield is:pulse peak voltage>gas volume ratio>pulse repetition frequency>total gas flow rate.Combined with these two parts of experiments,the optimal conditions for ammonia synthesis are finally obtained:Pulse peak voltage 16 kV,pulse repetition frequency 6 kHz,pulse rising edge 100 ns,V(N_(2))∶V(H_(2))=1∶1,and total gas flow rate 200 mL/min.Under this condition,the highest NH3synthesis rate is up to 923.08μmol/h and the energy yield is 0.30 g/kWh,respectively.

关 键 词：合成氨 等离子体 介质阻挡放电 纳秒脉冲电源 正交实验法 

分 类 号：O646.9[理学—物理化学]