磷酸硅铝分子筛的合成及其应用

磷酸硅铝(SAPO)分子筛是由PO4+、AlO4-及SiO2三种四面体单元构成的微孔型晶体.人工合成SAPO分子筛的方法主要是水热合成.采用不同的有机模板剂、混合物配比及pH值等因素会影响SAPO分子筛合成的结果.由于骨架呈负电性,具有可交换的阳离子,同时呈现出质子酸性,可以催化低碳物和甲醇的转化、烃类的异构化、烷基化以及汽车尾气净化等反应.SAPO分子筛还被广泛用作吸附剂和催化剂载体,是一种具有优异择形选择性、热稳定性和湿热稳定性的新型催化材料.     

新型催化材料--SAPO分子筛

磷酸硅铝分子筛（SAPO）是由SiO2、AlO2^-、PO2^＋三种四面体单元构成的微孔型晶体,具有从六元环至十二元环的孔道结构,孔径在0．3nm～0．8mm,骨架呈负电性,具有可交换的阳离子,被广泛用作吸附剂、催化剂和催化剂载体,是一种具有优异择形选择性、热稳定性和湿热稳定性的新型催化材料。SAPO分子筛可呈现出由中强酸到强酸的催化性能,几乎可用于所有的烃类反应。     

SAPO系列分子筛催化剂应用于正构烷烃异构化的研究进展

磷酸硅铝分子筛SAPO是由PO_4、AlO_4和SiO_4三种四面体构成的三维骨架结构微孔型晶体,具有优异择形选择性、离子交换性、酸性可调性和水热稳定性等特殊性能,广泛用于裂解、烷基化、聚合、重整、加氢、脱氢和水合等反应。综述了SAPO系列分子筛在正构烷烃异构化反应中的应用。SAPO作载体比传统载体制得的催化剂活性高;SAPO-11负载的贵金属催化剂有较高的活性和异构选择性;小粒径SAPO系列分子筛负载的高比表面积、高活性、高稳定性和强抗中毒性能的非贵金属催化材料是异构化催化剂的研究热点。展望了SAPO系列分子筛的研究方向及应用前景。     

SAPO分子筛性能的研究进展

磷酸硅铝(SAPO)分子筛作为一种新型的微孔型晶体,具有适宜的酸性和孔道结构以及优异的选择性和热稳定性,是一种良好的新型催化材料,被广泛应于与甲醇转化制烯烃、烃类的异构化和汽车尾气净化催化材料等方面,具有很好的开发潜力和发展前景。本文介绍了SAPO分子筛中Si原子的取代机理,综述了SAPO分子筛的酸性、吸附性能、热稳定性能和催化性能,概述了影响SAPO分子筛结构和性能的主要因素,包括反应物的组成配比、模板剂、硅源、介质等,并对SAPO分子筛目前存在的问题进行了分析和展望。     

SAPO合成因素的影响研究

磷酸硅铝分子筛(SAPO)作为新型的晶体分子筛,具有优异的性能,使得SAPO分子筛在许多烃类转化方面得到应用,在合成过程中受诸多因素的影响。介绍了SAPO系列分子筛的研究现状,总结了合成过程中SAPO的影响因素,并分别从原料及配比、晶化条件、介质、pH值、加料顺序等方面进行综述,改变任何一个影响因素对SAPO分子筛的种类、结晶度、晶貌、酸性、孔容、比表面积等都会产生一定影响。最后指出,提高烃类异构化反应的SAPO分子筛性能,需要对其酸性和孔道结构进行调节改性是急需解决的问题。     

TS-1钛硅分子筛的制备研究新进展

钛硅分子筛催化剂作为典型的环境友好催化剂体系被广泛应用于低浓度双氧水氧化的绿色有机合成工艺中.详细阐述了钛硅分子筛催化剂的2种制备方法经典的水热合成法及新型的气-固相同晶取代法,并重点指出这2种方法的优劣性.评述了钛硅分子筛催化剂工业化制备中急需解决的问题,指出气-固相同晶取代法二次合成钛硅分子筛由于其制备工序简便,因而具有更加显著的成本优势和广阔的工业应用前景.     

正庚烷异构化催化剂研究进展

阐述了当前正庚烷异构化所用的负载型催化剂和过渡金属碳化物和氧化物催化剂的研究进展,对催化剂性能的影响因素及对策进行了分析与讨论。正庚烷异构化催化剂中,研究较多的是以SAPO、HZSM-5和Y、B型分子筛为载体的贵金属催化剂,其中SAPO分子筛载体的性能较优,Pt比Pd具有更好的催化性能,非贵金属／分子筛催化剂的活性比贵金属／分子筛催化剂相差较大。过渡金属Mo、W的碳化物和氧化物也具有较好的正庚烷异构化性能,与碳氧化物或碳化物相比,部分还原氧化物催化正庚烷异构化活性和选择性要高得多,其活性甚至高于传统的Pt/USY双功能催化剂。展望了正庚烷异构化催化剂的研究方向和意义。     

碳六烯烃异构化制备2,3-二甲基-2-丁烯

通过 1 己烯异构化反应的固体酸分子筛催化剂的研究 ,发现ZSM 35和SAPO 11分子筛催化剂具有很好的 1 己烯异构化生成 2 ,3 二甲基 2 丁烯催化反应性能。SAPO 11分子筛上当1 己烯反应空速从 0 2h-1增加到 2 0h-1时 ,2 ,3 二甲基 2 丁烯收率从 5 0 8%降到 0 2 1% ,表明 1 己烯异构生成 2 ,3 二甲基 2 丁烯是慢反应。以工业混合碳六烯烃为原料在t =2 70℃ ,p=0 2MPa ,WHSV =1 0h-1,n(H2 )∶n(碳六烯烃 ) =2∶1反应条件下 ,考察SAPO 11分子筛催化剂用于混合碳六烯烃异构的反应性能 ,在 4 6h的反应过程中 ,2 ,3 二甲基 2 丁烯的收率保持在 8 5 %～ 10 % ,产生的裂解产物和聚合产物收率低于 1%。     

甲醇制低碳烯烃催化剂研究新进展

对甲醇制低碳烯烃催化剂的最新研究进展进行了综述,详细介绍了ZSM-5分子筛催化剂和SAPO34分子筛催化剂的改性及其在MTP/MTO过程中的反应行为,并对MTO催化剂的发展趋势进行了分析.     

加氢异构催化剂的研究进展

综述了近年来加氢异构催化剂的研究进展,介绍了β分子筛、丝光沸石、SAPO系列分子筛、固体超强酸等为载体的双功能催化剂,并对新型复合材料在这一领域的应用前景做了展望.     

SAPO-34 分子筛研究新进展

综述了关于SAPO-34分子筛在合成、结构、表面酸性及其调变、热稳定性和水热稳定以及MeAPSO-34分子筛等方面的研究近况，并阐述了该分子筛的典型催化反应及研究前景。     

SAPO分子筛在烃类异构化反应中的应用

介绍了SAPO分子筛在烯烃异构、烷烃异构、芳烃异构、异构脱蜡等化工过程的最新应用;综述了通过引入合适的金属离子对SAPO分子筛的酸性和孔道结构进行调节,有利于烃类异构化反应;认为有效提高SAPO分子筛的稳定性,是急需解决的问题。     

Vapour phase hydrogenolysis of biomass‐derived diethyl succinate to tetrahydrofuran over CuO?ZnO/solid acid bifunctional catalysts

BACKGROUND: Catalytic upgrading of fermentation‐derived succinic acid or its derivates (succinic acid esters and succinic anhydride) to value added chemicals has received great attention recently. The aim of this work is to provide a process for the production of tetrahydrofuran from succinic acid esters. RESULTS: The hydrogenolysis of biomass‐derived diethyl succinate was investigated over CuO? ZnO and CuO? ZnO/solid acid (HY, HZSM‐5, SAPO‐11 and Al₂O₃) catalysts in a fixed‐bed reactor. Over CuO? ZnO, gamma‐butyrolactone and 1,4‐butanediol can be selectively produced under appropriate reaction conditions, while the selectivity of tetrahydrofuran is relatively low due to the weak acidity of CuO? ZnO. Over CuO? ZnO/HZSM, both the formed 1,4‐butanediol and ethanol can be further converted to tetrahydrofuran and diethyl ether, while tetrahydrofuran is selectively produced over CuO? ZnO/HY. CuO? ZnO/Al₂O₃ and CuO? ZnO/SAPO exhibit slight improvements in terms of selectivity to tetrahydrofuran when compared with CuO? ZnO. CONCLUSION: CuO? ZnO/HY is an appropriate catalyst to produce tetrahydrofuran from biomass‐derived diethyl succinate with high activity, selectivity and stability. Furthermore, Brønsted acid sites with appropriate acid strength are responsible for the selective formation of tetrahydrofuran under the applied reaction conditions. Copyright © 2010 Society of Chemical Industry     

SAPO分子筛上氯甲烷催化转化制氯乙烯单体

采用水热合成法制备了SAPO分子筛,考察磷与铝物质的量比对SAPO分子筛催化转化氯甲烷制氯乙烯单体反应催化性能的影响.结果表明,SAPO-34在氯甲烷催化转化制备氯乙烯单体反应中,表现出较好的催化性能及稳定性.     

Effect of gas permeation temperature and annealing procedure on the performance of binary and ternary mixed matrix membranes of polyethersulfone,SAPO‐34, and 2‐hydroxy 5‐methyl aniline

This study investigated the effect of annealing time and temperature on gas separation performance of mixed matrix membranes (MMMs) prepared from polyethersulfone (PES), SAPO‐34, and 2‐hydroxy 5‐methyl aniline (HMA). A postannealing period at 120°C for a week extensively increased the reproducibility and stability of MMMs, but for pure PES membranes no post‐annealing was necessary for stable and reproducible performance. The effect of operation temperature was also investigated. The permeabilities of H₂, CO₂, and CH₄ increased with increasing permeation temperature from 35°C to 120°C, yet CO₂/CH₄ and H₂/CH₄ selectivities decreased. PES/SAPO‐34/HMA ternary and PES/SAPO‐34 binary MMMs exhibited the highest ideal selectivity and permeability values at all temperatures, respectively. For H₂/CO₂ pair, when temperature increased from 35°C to 120°C, selectivity increased from 3.2 to 4.6 and H₂ permeability increased from 8 to 26.5 Barrer for ternary MMM, demonstrating the advantage of using this membrane at high temperatures. The activation energies were in the order of CH₄ > H₂ > CO₂ for all membranes. PES/SAPO‐34/HMA membrane had activation energies higher than that of PES/SAPO‐34 membrane, suggesting that HMA acts as a compatibilizer between the two phases. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40679.     

Zeolite filled siloxane composite foams: Compression property

In this article, mechanical behavior under compression loads of an innovative adsorbent material, based on silicone composite foams filled with SAPO 34 zeolite, is presented. The innovative composite foams were obtained profiting by the dehydrogenative coupling of siloxane constituents. These new adsorbent systems have been proposed to overcome to the low mechanical stability of conventional SAPO‐34 coating for adsorption chiller. In this concern, static and cyclic compressive tests at room temperature have been carried out. Samples at increasing content of SAPO 34 zeolite were tested to evaluate the influence of the filler content on the mechanical behavior of the composite foam. The results showed that the presence of zeolite reduces the elastic limit of the foam and increases the strength. The foams evidenced also acceptable mechanical stability to cyclic compressive loads. The encouraging results confirm the possible use of these new composite foams as adsorbent materials for cyclic adsorption heat pumps. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46145.     

Krypton‐xenon separation properties of SAPO‐34 zeolite materials and membranes

Separation of the radioisotope ⁸⁵Kr from ¹³⁶Xe is an important target during used nuclear fuel recycling. We report a detailed study on the Kr and Xe adsorption, diffusion, and membrane permeation properties of the silicoaluminophosphate zeolite SAPO‐34. Adsorption and diffusion measurements on SAPO‐34 crystals indicate their potential for use in Kr‐Xe separation membranes, but also highlight competing effects of adsorption and diffusion selectivity. SAPO‐34 membranes are synthesized on α?alumina disk and tubular substrates via steam assisted conversion seeding and hydrothermal growth, and are characterized in detail. Membrane transport measurements reveal that SAPO‐34 membranes can separate Kr from Xe by molecular sieving, with Kr permeabilities around 50 Barrer and mixture selectivity of 25–30 for Kr at ambient or slight sub‐ambient conditions. The membrane transport characteristics are modeled by the Maxwell‐Stefan equations, whose predictions are in very good agreement with experiment and confirm the minimal competing effects of adsorption and diffusion. © 2016 American Institute of Chemical Engineers AIChE J, 63: 761–769, 2017     

SAPO-34分子筛研究进展

综述了SAPO-34分子筛在合成、结构、酸性、热稳定性及水热稳定性等物化表征方面以及在MTO反应中应用的研究近况,重点介绍了SAPO-34分子筛合成及其在MTO反应中应用的影响因素。