Mo_(12)Bi_(1.2)Fe_(3)Co_(8)K_(0.4)用于异丁烯气相氧化制甲基丙烯醛  

Mo_(12)Bi_(1.2)Fe_(3)Co_(8)K_(0.4) for selective oxidation of isobutene to methacrolein

作　　者：王加升[1] 王庆荣 吴友根 包明[1] WANG Jiasheng;WANG Qingrong;WU Yougen;BAO Ming(State Key Laboratory of Fine Chemicals,Dalian University of Technology,Panjin 124221,Liaoning,China)

机构地区：[1]大连理工大学精细化工国家重点实验室,辽宁盘锦124221

出　　处：《精细化工》2024年第8期1774-1779,共6页Fine Chemicals

基　　金：国家自然科学基金项目(22278063)。

摘　　要：以(NH_(4))_(6)Mo_(7)O_(24)·4H_(2)O、Bi(NO_(3))_(3)·5H_(2)O、Fe(NO_(3))_(3)·9H_(2)O、Co(NO_(3))_(2)·6H_(2)O和KNO_(3)为前驱体金属盐,通过共沉淀法制备了一系列MoBiFeCoK混合氧化物催化剂,考察了主金属Mo、Bi,助金属Fe、Co和掺杂金属K含量对催化剂催化异丁烯气相氧化反应的影响,通过SEM、EDX、XRD、NH_(3)-TPD对掺杂K前后的催化剂进行了表征,同时对催化异丁烯气相氧化反应条件进行了优化,并测试其100 h的催化稳定性。结果表明,Bi、Fe、Co和K的含量对MoBiFeCoK混合氧化物催化剂催化异丁烯气相氧化反应的性能有显著影响,其中,Mo_(12)Bi_(1.2)Fe_(3)Co_(8)K_(0.4)表现出最优催化性能;K的掺杂降低了催化剂酸量(从Mo12Bi1.2Fe3Co8的15.27μmol/g降至Mo_(12)Bi_(1.2)Fe_(3)Co_(8)K_(0.4)的5.91μmol/g),并明显提升主产物甲基丙烯醛(MAL)的选择性;异丁烯气相氧化反应的最佳条件为:以0.66 g Mo_(12)Bi_(1.2)Fe_(3)Co_(8)K_(0.4)为催化剂,反应温度320℃,n(O_(2))∶n(异丁烯)(氧烯比)=10∶1,体积空速(GHSV)=2000h^(-1)。在该条件下,Mo_(12)Bi_(1.2)Fe_(3)Co_(8)K_(0.4)在100h的催化异丁烯气相氧化反应中表现稳定,异丁烯转化率保持在98.6%,MAL选择性保持在86.4%。A series of MoBiFeCoK mixed-oxide catalysts were prepared by co-precipitation method using(NH_(4))_(6)Mo_(7)O_(24)·4H_(2)O,Bi(NO_(3))3·5H_(2)O,Fe(NO_(3))_(3)·9H_(2)O,Co(NO_(3))_(2)·6H_(2)O,and KNO_(3) as precursor metal salts.The effects of contents of main metals Mo and Bi,co-metals Fe and Co,and doped K on the catalytic performance of the catalysts for gas-phase oxidation reaction of isobutene were investigated.The catalysts before and after doping with K were characterized by SEM,EDX,XRD,and NH_(3)-TPD,while the catalytic conditions for the gas-phase oxidation reaction of isobutene were optimized and the catalytic stability of the catalysts for 100 h were evaluated.The results showed that the contents of Bi,Fe,Co,and K had a significant effect on the catalytic performance of MoBiFeCoK mixed-oxide catalysts for the gas-phase oxidation reaction of isobutene,with Mo_(12)Bi_(1.2)Fe_(3)Co_(8)K_(0.4) showing the best catalytic performance.The doping of K reduced the amount of catalyst acid center(from 15.27μmol/g of Mo12Bi1.2Fe3Co8 to 5.91μmol/g of Mo_(12)Bi_(1.2)Fe_(3)Co_(8)K_(0.4))and significantly enhanced the selectivity of the main product methacrolein(MAL).Under the optimal reaction conditions of 0.66 g Mo_(12)Bi_(1.2)Fe_(3)Co_(8)K_(0.4) as catalyst,reaction temperature 320℃,n(O_(2))∶n(isobutene)(oxygen-alkene ratio)=10∶1,and gaseous hourly space velocity(GHSV)=2000 h^(-1),the catalytic isobutene gas-phase oxidation reaction of Mo_(12)Bi_(1.2)Fe_(3)Co_(8)K_(0.4) was stable for 100 h,with the isobutene conversion of 98.6%,and the MAL selectivity of 86.4%.

关 键 词：甲基丙烯醛 选择性氧化 异丁烯 K掺杂 催化技术 

分 类 号：TQ426[化学工程] TQ224.1