79808-30-3Relevant articles and documents
Screening of solid acid catalysts for etherification of glycerol with isobutene under identical conditions
Bozkurt, ?zge Deniz,Ba?lar, Nur,?elebi, Serdar,Uzun, Alper
, p. 483 - 494 (2019/08/20)
We compared the performance of more than 70 solid acid catalysts with Br?nsted acid function for the etherification of glycerol with isobutene under identical reaction conditions of 75 °C, 10 bar, 6 h and with an isobutene/glycerol molar ratio of 3/1. The catalysts were selected from a wide range of solid acid catalysts including ion exchange resins, zeolites, silica, and heteropolyacids, and their counterparts modified by simple treatments, with more than half of them being investigated for the first time for this reaction. For the modified commercial acid catalysts, the desired glycerol tertiary butyl ether (DTBGE and TTBGE) selectivity improved from 75 to 87 wt% upon partial cation exchange of the sulfonic acid protons in Amberlyst type ion exchange resins with Na+ cations; from 66 to 85 wt% by hydrothermal steam treatment of zeolite H-Y (SiO2/Al2O3 = 80); and from 75 to 80 wt% with partial La+-exchange of zeolite H-Beta (SiO2/Al2O3 = 300), all at high (90–100%) glycerol conversion. Impregnation of the heteropolyacids, tungstosilicic acid (TSA) and tungstophosphoric acid (TPA), on silica at a loading of 50 wt% provided a glycerol conversion of higher than 65 wt% and with a desired ether selectivity in the range of 62 to 76 wt%. In general, total ether selectivity increased with decreasing acid capacity for ion exchange resins, while the desired ether selectivity was enhanced with increasing acid strength for zeolites and supported heteropolyacids on mesoporous silica. Data present a detailed guideline for the selection of solid acid catalysts for the etherification of glycerol with isobutene.
Etherification of glycerol with tert-butyl alcohol over sulfonated hybrid silicas
Estevez,López,Jiménez-Sanchidrián,Luna,Romero-Salguero,Bautista
, p. 155 - 163 (2016/09/07)
The etherification of glycerol with tert-butyl alcohol has been carried out in the liquid-phase on different sulfonic acid functionalized hybrid silicas obtained by oxidative cleavage of tetrasulfide bridges. These materials exhibited different textural properties and acidities ranging from 0.5 to 2.3?mmol?g?1. First of all, different experimental variables, including the reactant ratio and temperature have been tested and all catalysts were essayed under optimal conditions. The best catalytic behavior of the hybrid silicas was obtained on S50TS50O (Yh-GTBE?=?28%) at 75?°C and autogenous pressure. In fact, the glycerol conversion obtained on S50TS50O, clearly surpassed that obtained on A-15 (74 and 51%, respectively). The acidity and the hydrophilic character of the sulfonated hybrid silicas solids have been found to be key parameters for their catalytic activity whereas the surface area and porosity do not seem to be advantageous for this reaction. All catalysts were reused and subjected to an extensive characterization.
Catalytic synthesis of glycerol tert-butyl ethers as fuel additives from the biodiesel by-product glycerol
Huang, Rui,Kim, Eui Yong
, (2015/05/27)
Glycerol is a major by-product in the biodiesel production process. Every 100 kg of biodiesel produced generates approximately 10 kg of crude glycerol. As the biodiesel industry has expanded rapidly in recent years, finding new uses of the excess crude glycerol is important. Many studies have examined alternative uses of crude glycerol. One of them is the use of glycerol derivatives, such as glycerol tert-butyl ethers as fuel additives. In this paper, the etherification kinetics of glycerol with tert-butyl alcohol to glycerol tert-butyl ethers was studied using an Amberlyst catalyst. The influences of the catalyst type and loading, reaction time, molar ratio, and temperature were investigated in detail.