乙二醇热还原法制备生物炭负载纳米钯催化剂及其催化脱氢性能

Preparation of Biochar Loaded Nano Pd Catalyst by Hot Ethylene Glycol Reduction and Its Property for Catalytic Dehydrogenation

以生物炭(BC)为载体,环境友好的乙二醇(EG)为还原剂,一锅法制备出生物炭负载纳米钯催化剂(Pd/BC),并应用其催化十二氢-N-乙基咔唑(12H-NEC)脱氢反应。采用XRD、XPS、TEM以及N_(2)物理吸附等分析仪器对所制备的BC的结构、组成和形貌进行了表征。结果表明,控制还原温度可以有效地将Pd^(2+)还原为Pd^(0),生成的Pd纳米颗粒(Pd NPs)均匀分布在BC表面,粒径在3.25~9.67nm之间,平均粒径为6.03nm,无明显团聚。在160℃下EG热还原6h所制备的催化剂(Pd/BC-160/6)催化12H-NEC脱氢反应效果最佳,当脱氢温度为180℃时,6h时释氢率达到93.7%,催化剂重复4次后释氢率仍可保持在90.3%。

The biochar supported nano-palladium catalysts(Pd/BC)are prepared by one-pot method using biochar(BC)as the carrier and environmentally friendly ethylene glycol(EG)as the reducing agent,and are applied to catalyze the dehydrogenation of dodecahydro-N-ethylcarbazole(12H-NEC).The structure,composition and morphology of the prepared BC are characterized by XRD,XPS,TEM and N_(2)physical adsorption.The re sults show that Pd^(2+)can be effectively reduced to Pd^(0)by controlling the reduction temperature,and the generated Pd nanoparticles(Pd NPs)uniformly distribute on the surface of BC with the particle size ranging from 3.25 nm to 9.67 nm,and the average particle size is 6.03 nm,without obvious agglomeration.Pd/BC-160/6 catalyst prepared by EG thermal reduction at 160℃for 6 h has the best catalytic performance for 12H-NEC dehydrogenation.The hydrogen release efficiency reaches 93.7%at the dehydrogenation temperature of 180℃for 6 h,and remains 90.3%after the catalyst is reused for 4 times.