甲醇存在时镧改性HZSM-5催化剂对噻吩转化反应的影响  

Study on the Effect of La-Modified HZSM-5 Zeolite on the Transformation Reaction of Thiophene in the Presence of Methanol

作　　者：罗立文[1] 于慧征[1] 孙琳琳[1] 夏道宏[1] 吕仁庆[1] 

机构地区：[1]中国石油大学化学化工学院重质油国家重点实验室,山东东营257061

出　　处：《高校化学工程学报》2007年第1期70-75,共6页Journal of Chemical Engineering of Chinese Universities

基　　金：重质油国家重点实验室开放课题(E030407-2);教育部优秀青年教师资助计划项目(20011863)

摘　　要：探讨了在甲醇存在时,La改性HZSM-5(硅铝摩尔比为25)分子筛催化剂对噻吩在固定床微型反应器中的催化脱硫转化反应的影响。通过对反应温度、甲醇含量、La负载量、质量空速等各影响因素的分析,得到以下的结论:只有在350℃以上时,噻吩有比较好的转化效果,在HZSM-5(或La-HZSM-5)分子筛催化剂上噻吩的转化率与硫化氢的产率分别达到了30.5%(或51.0%)、8.0%(或18.0%)以上,同一温度下或在同一甲醇浓度时,在La-HZSM-5分子筛催化剂上噻吩的转化率与硫化氢的产率比在HZSM-5分子筛催化剂上分别高许多;含活性氢物质甲醇的浓度是甲醇与溶剂苯的体积比为0.5时,在HZSM-5(或La-HZSM-5)分子筛催化剂上噻吩的转化率与硫化氢的产率分别达到了最大值15.3%(或51.3%)、6.5%(或18.1%)。掺镧的HZSM-5催化剂对噻吩的催化转化有促进作用,掺镧量为1.0%时噻吩的转化率和硫化氢的产率分别达到了51.3%和18.1%;质量空速对噻吩的催化转化的影响主要体现在影响噻吩在催化剂床层上的停留时间,质量空速为14.4h?1比较合适,因为无论有无甲醇存在,在此空速下在HZSM-5或La-HZSM-5分子筛催化剂上都分别出现了最高的噻吩转化率与最高的硫化氢产率。Using simulated fuel oil containing thiophene （1000μg·g^-1） as simulated organosulfurs in fuel oil, the effect of La-modified HZSM-5 on the catalytic desulphurization of fuel oil in the presence of methanol was studied in a fixed bed micro-reactor. According to the comparison between the results of desulfurization over La-modified HZSM-5 and that over HZSM-5 （molar ratio of silica to alumina is 25）, and also according to the analysis of the effects of various factors, such as reaction temperature, methanol content, amount of loaded La and the mass hourly space velocity （MHSV） used, several conclusions were obtained as follows. The thiophene can have a higher conversion ratio only when the temperature is above 350℃. At the same reaction temperature or with the same methanol concentration, using La-modified HZSM-5 the thiophene conversion ratio and the H2S yield are much higher than those of using HZSM-5. When the volumetric ratio of the activated hydrogen substance methanol to solvent benzene is 0.5 and the amount of La loaded on La-modified HZSM-5 is 1.0% （wt）, the conversion ratio of thiophene and the H2S yield over La-modified HZSM-5 （or HZSM-5） reach their maximum values, i.e., conversion ratio of 51.3% （or 15.3%） and H2S yield of 18.1% （or 6.5%）, respectively. The suitable MHSV is 14 h^-1, since no matter the desulfurization conducts with or without the presence of methanol, under this MHSV both the thiophene conversion ratio and the H2S yield over La-modified HZSM-5 or HZSM-5 are at their each own maximum value separately.

关 键 词：噻吩 ZSM-5 分子筛 La改性 脱硫 转化反应 

分 类 号：O643.32[理学—物理化学] TE624.55[理学—化学]