Cu-SSZ-13的合成与金属改性及催化MTO性能  

Synthesis and Metal-Modification of Cu-SSZ-13 Molecular Sieves and Their Catalytic Performance in MTO Reaction

作　　者：赵飞[1] 李渊[1] 张岩[1] 谭小耀[1] ZHAO Fei LI Yuan ZHANG Yan TAN Xiao-yao(School of Environmental and Chemical Engineering, Tianjin Polytechnic University, Tianjin 300387, Chin)

机构地区：[1]天津工业大学环境与化学工程学院,天津300387

出　　处：《精细化工》2017年第2期179-185,共7页Fine Chemicals

基　　金：国家自然科学基金项目(21176187)~~

摘　　要：以低廉的铜氨络合物(Cu-TEPA)为模板剂,通过原位水热合成法制备了Cu-SSZ-13。考察了两种铜盐和氢氧化钠用量对Cu-SSZ-13的晶相结构和形貌的影响,测试了两种铜盐制备的Cu-SSZ-13和金属改性的Cu-SSZ-13在甲醇制烯烃(MTO)中的催化性能。用XRF、XRD、SEM、N2等温吸附脱附(BET)和NH3程序升温脱附(NH3-TPD)对催化剂进行了表征。结果表明:碱度对Cu-SSZ-13的结晶度有很大影响,较高或较低的碱度会导致方沸石杂晶的产生,甚至生成纯相方沸石,n(Na2O)∶n(Al2O3)的较佳值为4.7~5;在MTO反应中,硝酸铜制备的CuSSZ-13的氢转移反应剧烈,反应初期丙烷选择性达到40%,远高于硫酸铜制备的Cu-SSZ-13的丙烷选择性(19%),因此,在抑制副反应发生上,Cu-SSZ-13/Cu SO4要优于Cu-SSZ-13/Cu(NO3)2。锰改性的Cu-SSZ-13明显提高了抗积炭失活能力,在反应温度440℃、质量空速(WHSV)5 h-1条件下,催化寿命从未改性的30 min延长到了65 min。Molecular sieve Cu-SSZ-13 was synthesized by in situ hydrothermal method using a low-cost copper amine complex（Cu-TEPA） as a template. The effects of two copper salts and dosage of sodium hydroxide on the crystal phase and morphological of the obtained Cu-SSZ-13 were studied. Besides,the catalytic performance of Cu-SSZ-13 prepared with two copper salts and metal modified Cu-SSZ-13 for methanol to olefins（MTO） was evaluated. These catalysts were characterized by XRF,XRD,SEM,BET and NH3-TPD techniques. The results showed that alkalinity had a great influence on the crystallinity of Cu-SSZ-13. If the alkalinity was excessively high or low,analcime zeolite as an impurity or pure phase would be produced. During the reaction of MTO,hydrogen transfer reaction of Cu-SSZ-13 prepared with cupric nitrate was intense,and the propane selectivity reached 40% in the early stage of the reaction,far higher than that of Cu-SSZ-13 prepared with cupric sulfate（19%）,therefore,Cu-SSZ-13/Cu SO4 was superior to Cu-SSZ-13/Cu（NO3）2on inhibiting side reaction. Cu-SSZ-13 modified with manganese exhibited an obvious inhibition of coking deactivation,its lifetime extended from 30 to 65 min at 440 ℃and WHSV 5 h-1.

关 键 词：Cu-SSZ-13 甲醇制烯烃 铜盐 碱度 金属改性 催化与分离提纯技术 

分 类 号：O643.36[理学—物理化学] TQ426.94[理学—化学]