正丁烷氧化制顺酐VPO催化剂失活研究  

Deactivation of VPO oxide catalyst for the oxidation of n-butane to maleic anhydride

作　　者：陈炳旭 顾龙勤[1] 曾炜[1] 陈亮[1] Chen Bingxu;Gu Longqin;Zeng Wei;Chen Liang(State Key Laboratory of Green Chemical Engineering and Industrial Catalysis,Sinopec Shanghai Research Institute of Petrochemical Technology,Shanghai 201208,China)

机构地区：[1]中国石油化工股份有限公司上海石油化工研究院,绿色化工与工业催化国家重点实验室,上海201208

出　　处：《工业催化》2022年第7期68-72,共5页Industrial Catalysis

摘　　要：研究正丁烷氧化制顺酐用VPO催化剂稳定性规律及失活机理。采用固定床反应器对催化剂进行近6000 h稳定性测试,并通过XRD、FT-IR、N_(2)吸附-脱附、XPS和氧化还原滴定等手段对反应前后催化剂进行表征。结果表明,在无补磷条件下,随着反应的进行,催化剂性能逐渐下降,V^(5+)相态逐渐减少,V^(4+)相态稳定存在,V平均价态降低;催化剂表面的P先行流失,接着体相的P扩散至表面,并随着反应进行继续流失,同时,催化剂的比表面积显著增加,造成催化剂的失活。The stability and deactivation mechanism of the vanadium phosphorus oxide catalyst for n-butane oxidation to maleic anhydride(MA)were studied.The stability test of the catalyst for nearly 6000 h was performed using a fixed-bed reactor.The fresh and spent catalysts were characterized by XRD,FT-IR,N_(2) adsorption-desorption,XPS and redox titration.The results suggested that without phosphorus addition,the catalytic performance gradually decreased,along with the decrease of the phase of V^(5+) and the average vanadium valence of the catalysts.The phase of V^(4+) stably exists over the fresh and spent catalysts.The surface phosphorus was firstly volatilized followed by the diffusion of the bulk phosphorous to the surface,and as the reaction progress the catalysts underwent further loss of surface phosphorus.Meanwhile,the specific surface area of the deactivated catalyst increased significantly.The phosphorus loss and the increased specific surface area are the main reasons for the catalyst deactivation.

关 键 词：精细化学工程 正丁烷 顺酐 钒磷氧化物 选择氧化 催化剂失活 

分 类 号：TQ426.94[化学工程]