92867-55-5Relevant articles and documents
Microwave-assisted synthesis of sulfonic acid-functionalized microporous materials for the catalytic etherification of glycerol with isobutene
Gonzalez, Maria Dolores,Salagre, Pilar,Taboada, Elena,Llorca, Jordi,Cesteros, Yolanda
, p. 2230 - 2239 (2013)
Commercial Beta, ZSM-5 and mordenite zeolites and commercial montmorillonite K-10 were successfully sulfonated by a one-step simple method using microwaves. Different amounts of the sulfonating agent were required to maximize the incorporation of sulfonic groups for each structure. This has been related to the different dealumination degree suffered by the starting samples during sulfonation together with the different accessibility of the silanols to the sulfonic groups depending on the arrangement and size of their pores. All optimised sulfonated catalysts showed total conversion and very high selectivity (79-91%) to h-GTBE (glycerol di- and tri-ethers), in spite of their microporosity, due to the incorporation of the sulfonic groups that led to a higher number and strength of Bronsted acid sites. Pore size and arrangement together with the external surface area of the catalysts affected the accessibility of the acid sites to the reactants, explaining the evolution of the catalytic results with time for each structure.
Cesium exchanged tungstophosphoric acid supported on tin oxide: An efficient solid acid catalyst for etherification of glycerol with tert-butanol to synthesize biofuel additives
Srinivas,Raveendra,Parameswaram,Prasad, P.S. Sai,Lingaiah
, p. 7 - 14 (2016)
Cesium exchanged tungstophosphoric acid (CsTPA) supported on tin oxide catalysts were prepared and their physio-chemical properties were derived from X-ray diffraction, FT-IR, laser Raman spectroscopy and temperature programmed desorption of NH3/sub
Tuning the acidic and textural properties of ordered mesoporous silicas for their application as catalysts in the etherification of glycerol with isobutene
González, María Dolores,Salagre, Pilar,Mokaya, Robert,Cesteros, Yolanda
, p. 171 - 178 (2014)
Several silicas (MCM-41, SBA-15 and HMS) were acid-modified by incorporating aluminium or by introducing phosphorus species or sulfonic groups. The modified silicas maintained mesostructural ordering and a narrow pore size distribution. However, Their surface area and pore volume was lower than that of unmodified samples. The incorporation of aluminum in the structure of MCM-41 and SBA-15 increased the amount of Br?nsted acid sites, leading to greater catalytic activity (i.e., higher conversion values) for glycerol etherification with isobutene than pure silicas, but their relatively weak acid strength resulted in low selectivity to di- and tri-tertiary butyl ethers of glycerol (h-GTBE). The introduction of phosphoric groups, with higher acidity strength, improved the selectivity to h-GTBE, and glycerol triether was detected in low amounts. Interestingly, HMS synthesized with dodecylamine and later sulfonated exhibited total conversion and 84% of selectivity to h-GTBE (26% to glycerol triether) after 24 h of reaction. The presence of textural mesoporosity in HMS reduced diffusion limitations, and consequently increased the incorporation of sulfonic groups and their accessibility, leading to higher catalytic activity.
Preparation method of 1,3-propanediol
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Paragraph 0069-0072, (2019/09/17)
The invention discloses a preparation method of 1,3-propanediol, and relates to the technical field of chemical synthesis. According to the scheme, glycerol is used as a raw material to prepare 1,3 propylene glycol by using a functional group directional protection method, that is, a terminal hydroxyl group is selectively protected through an etherification reaction, secondary hydroxyl group is removed through a sulfonylation reaction and a reduction reaction, and a protective group is removed. The process of the preparation method provided by the invention has the characteristics of high yield, few byproducts, low cost, easy separation and the like, is an environment-friendly and economical route, overcomes the defects of complex operation and low yield in the prior art, and has a wide development prospect.
