Beta分子筛改性技术的研究

Modification technology of beta zeolite

考察了酸洗、水热处理温度及次数等改性工艺条件对Beta分子筛性质的影响规律,结果表明:Beta分子筛的改性工艺为80℃酸洗2h,650℃水热处理1h。在优化的改性工艺条件下对不同n(SiO_2)∶n(Al_2O_3)(以下简称硅铝比)的Beta分子筛进行了改性研究:改性后Beta分子筛的硅铝比随着Beta分子筛原料硅铝比的增加而增加,相对结晶度受起始原料的影响很小;随着硅铝比的提高,Beta分子筛的表面总酸量均降低;Beta分子筛的硅铝比越大,比表面积越大,孔体积也越大。

The influence of temperature and time of the acid washing and hydrothermal treatment on Beta zeolite properties was examined in detail,the results revealed that acid washing at 2hand 80℃and 2hhydrothermal treatment at 650℃ are the best modification operating conditions.The different SiO_2/Al_2O_3 ratio of Beta zeolite are systematically modified using optimized modification operating conditions.Beta zeolite modified from higher SiO_2/Al_2O_3 ratio of the starting Beta also has higher SiO_2/Al_2O_3 ratio.Crystallinity of starting Beta zeolite has less effect on the modified Beta zeolite.As the SiO_2/Al_2O_3 ratio of starting Beta increased,total acid amount of modified Beta decreased.When the SiO_2/Al_2O_3 ratio of starting Beta is bigger,the surface area and pore volume is higher.