β型分子筛
β型分子筛是一种具有三维十二元环孔结构的高硅沸石， 其结构特点是两个四元环和四个五元环的双六元环单位晶穴结构，主孔道直径0.56-0.75nm，热稳性较高。β型分子筛只有孔道没有笼，因此β型分子筛可以进行阳离子全部交换。β型分子筛对环已烷、正已烷，水的吸附量都较大，均在14%以上。β型分子筛的孔道特点使得它在裂解反应中对链状烃断裂选择性较强，如果使用在石油烃的裂解过程中有可能获得高炭数低凝点的裂解产物，因此β型分子筛做为以石油烃为原料的炼油催化剂有很好的工业应用前景，它所产生的柴油凝点降低很多，是一种新型的生产低凝点柴油高中油型加氢裂化催化剂。
改性的β型分子筛加入FCC催化剂中可以降低催化裂化的烯烃含量。同时又能适当提高辛烷值。目前，降烯烃催化剂在降低汽油中的烯烃同时会出现辛烷值下降的问题。因此改性的β型分子筛引入FCC催化剂中对解决这一问题有重要意义。对于甲苯、三甲苯和C9等歧化反应及转烷基反应，β型分子筛具有稳定性和高选择性。
在精细化工方面，β型分子筛用于丙烯烷基化、乙烯烷基化生成异丙苯和乙苯，并已在工业上应用；我厂在β沸石的基础上开发成功了脱氨脱水催化剂，在脱氨脱水等反应中具有很好的活性和选择性。我厂每年可生产400吨β型分子筛，硅铝比为20至全硅。产品的质量达到国际水平。
产品指标Technical information：
样品Sample |
Si02/A1203 |
比表面Surface Area（m2/g） |
Na2O% |
正己烷吸附量n-hexane adsorptive capacity (mg/g) |
Hβ |
23 |
583 |
≤0.1% |
≥130 |
Hβ |
25 |
605 |
≤0.08% |
≥130 |
Hβ |
40 |
570 |
≤0.05% |
≥130 |
Hβ |
50 |
597 |
≤0.05% |
≥130 |
Hβ |
500 |
524 |
≤0.005% |
≥130 |
Hβ |
≥1000 |
442 |
≤0.003% |
≥120 |
Introduction of β-zeolite
β-zeolite is one kind of highSi02/Al2O3 ratio zeolites with three-dimensional twelve-membered rings, composed of double six-membered rings with two four-membered rings and four five-membered rings. The diameter of the main duct of β-zeolite is 0.56×0.76nm. β-zeolite only has duct without cages, so it is able to exchange all the cations. β-zeolite has relatively large absorptive capacity of cyclohexane and n-hexane, each above 14%, and also has a high thermostability.
Because of the feature of duct, β-zeolite has high selectivity of chain hydrocarbon in cracking reaction. Used into petroleum hydrocarbon cracking industry to obtain of high carbon low freezing-point cracking product, β-zeolite is able to decrease the solidifying point of diesel oil. β-zeolite is a new hydro cracking catalyst producing diesel oil with low solidifying point, so it has a good industrial application prospect in oil refining industry.
In petrochemical industry, at present, the decreasing olefin catalyst can both reduce olefin and octane ratio in gasoline. Adding modified β-zeolite into FCC catalyst is able to decrease the content of olefin in catalysts cracking reaction, and increase octane ratio simultaneously. So the FCC catalyst with modified β-zeolite will play important role to solve this question. Furthetmore, for some dismutation reaction such as toluene, dimethyl benzene, C9 and transalkylation reaction, β-zeolite has excellent stability and selectivity.
In fine chemical industry, β-zeolite has already been used both in the alkylation of propene to isopropyl-benzene and ethane to ethylbenzene. β-zeolite is the catalyst with high activity and selectivity for dehydration and deammonia reaction.
Our factory is able to produce 400 tons of β-zeolite which SiO2/Al2O3 ratio is from 20 to pure silicon per year. Our product, β-zeolite, possesses excellent competitive position of quality and price in the internal and international market
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