摘要
分别以浸渍法和分步浸渍法制备了Ni/SAPO-11催化剂和Ni-Sn/SAPO-11双金属催化剂,利用XRD、F T-IR、NH_3-TPD、Py-IR、SEM等手段对其进行了表征,考察了Sn含量对分子筛结构和酸性的影响,并以正庚烷临氢异构化为探针反应,考察了Sn含量及反应条件对催化剂临氢异构化性能的影响.结果表明,在我们所考察的Sn含量范围(加入锡含量)内,所制备的催化剂均能保持SAPO-11分子筛晶相,金属Sn均可调节催化剂酸性.加入Sn可以明显提高正庚烷的转化率和异庚烷的选择性,其中,在氢烃比n(H_2)/n(n-C_7H_(16))为14、H_2流速为30m L/min、还原温度为430℃、还原时间为5 h、反应温度为300℃、反应时间为5 h、重时空速(WHSV)为6.8 h-1、反应压力为常压条件下,5%Ni-4%Sn/SAPO-11催化剂的催化性能较佳,其正庚烷转化率可达43%,异庚烷的选择性可达71%.
Ni/SAPO-11 catalyst and Ni-Sn/SAPO-11 bimetallic catalyst were prepared by impregnation and step by step impregnation method, respectively. The influences of Sn content on the structure and acidity of the molecular sieve were investigated by XRD, FT-IR, NH3-TPD, Py-IR and SEM characterizations. Besides, the effect of Sn content and reaction conditions on the isomerization performance of the catalyts was examined by n-heptane hydroi- somerization reaction. The results showed that the catalysts with different Sn content were able to maintain the crys- talline phase of SAPO-11 molecular sieve and adjust the acidity of catalyst in the investigated content. The addition of Sn can significantly improve both the conversion of n-heptane and the selectivity of isoheptane. The conversion and isomerization selectivity of 5%/Ni-4% Sn/SAPO- 11 catalyst can reach 43% and 71%, respectively, when n（H2）/rt（rt-C7 H16） was 14, H2 flow was 30 mL/min, reduction temperature was 430 ℃ , reduction time was 5 h, reaction temperature was 300 ℃ , reaction time was 5 h, WHSV was 6.8 h-1 and reaction pressure was atmos- pheric pressure.
出处
《分子催化》
EI
CAS
CSCD
北大核心
2017年第5期446-454,共9页
Journal of Molecular Catalysis(China)
基金
东北石油大学校青年基金(NEPUQN2015-1-08)~~
