La-Ni-Mo-B非晶态催化剂的制备及其苯酚加氢脱氧催化性能  

Preparation of La-Ni-Mo-B Amorphous Catalyst and Its Catalytic Properties for Hydrodeoxygenation of Phenol

作　　者：王威燕[1] 张小哲[1] 杨运泉[1] 杨彦松[1] 彭会左[1] 罗和安[1] 

机构地区：[1]湘潭大学化工学院,湖南湘潭411105

出　　处：《物理化学学报》2012年第5期1243-1251,共9页Acta Physico-Chimica Sinica

基　　金：湘潭大学资助基金(2011XZX11);湖南省教育厅开放基金(10K062)资助项目~~

摘　　要：以NaBH4为还原剂采用化学还原法制备出La-Ni-Mo-B非晶态催化剂,用扫描电子显微镜(SEM)、X射线衍射(XRD)、电感耦合等离子发射光谱(ICP-AES)、X射线光电子能谱(XPS)等手段对催化剂进行表征,研究了助剂La对Ni-Mo-B催化剂催化性能的影响.结果显示,加入适量助剂La能显著减小催化剂粒径,增加Ni0含量,促进Mo6+还原生成Mo4+,但过量La会覆盖Ni0和Mo4+的活性位点.催化剂的高加氢活性主要归因于其非晶态结构和高Ni0含量,高脱氧活性主要归因于其高Mo4+含量.在苯酚的加氢脱氧(HDO)反应中,La-Ni-Mo-B非晶态催化剂催化苯酚HDO反应主要按照加氢-氢解的路径进行的,显著降低了产物中芳烃含量.通过优化反应条件,催化苯酚的转化率和脱氧率都可达到99.0%.高温下La-Ni-Mo-B非晶态催化剂失活的主要原因是非晶态结构的破坏.Lanthanum-promoted Ni-Mo-B amorphous catalysts were prepared by chemical reduction of the corresponding metal salts with sodium borohydride aqueous solution.Scanning electron microscopy（SEM）,X-ray diffraction（XRD）,inductively coupled plasma atomic emission spectrometry（ICP-AES）,and X-ray photoelectron spectroscopy（XPS）were used to characterize the resulting materials.Phenol was used as model compound to test the hydrodeoxygenation（HDO）activity of the La-Ni-Mo-B amorphous catalysts.Adding lanthanum could decrease the particle size,increase the content of Ni 0 and promote the reduction of Mo 6＋ to Mo 4＋.But excess lanthanum would cover some of the Ni 0,and Mo 4＋ active sites.The high hydrogenation activity was attributed to the amorphous structure of the catalyst and the high content of Ni 0 and the high degree of deoxygenation was attributed to the high content of MoO 2.The HDO reation of phenol on the La-Ni-Mo-B amorphous catalyst proceeded with a hydrogenation-dehydration route,thus decreasing the aromatic content of the HDO products.Both the conversion and the total deoxygenation degree were up to 99.0%.The deactivation of the La-Ni-Mo-B amorphous catalysts during the HDO reation of phenol at high temperature was mainly caused by the crystallization of the amorphous structure.

关 键 词：非晶态催化剂 La-Ni-Mo-B 加氢脱氧 苯酚 生物油 

分 类 号：O643.36[理学—物理化学]