15220-85-6Relevant articles and documents
Method for isobutylene from tert-butanol
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Paragraph 0031-0045; 0054, (2021/07/06)
In the dehydration reaction of tert - butanol, the specific surface area is 30m. 2 Zirconia oxide (ZrO) above/g2 Using a solid acid catalyst. Provided is a process for preparing isobutylene which can show high conversion of tert - butanol and high selectivity to isobutylene while inhibiting oligomerization and side reactions of isobutylene. A method for producing isobutylene using tert - butanol is provided to obtain high purity isobutylene without adding a separate distillation process with high conversion of tert-butanol and isobutylene.
HYDROTHERMAL PRODUCTION OF ALKANES
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Paragraph 0022, (2021/04/17)
Synthesizing an alkane includes heating a mixture including an alkene and water at or above the water vapor saturation pressure in the presence of a catalyst and one or both of hydrogen and a reductant, thereby hydrogenating the alkene to yield an alkane and water, and separating the alkane from the water to yield the alkane. The reductant includes a first metal and the catalyst includes a second metal.
Mechanism and Kinetics of Acetone Conversion to Isobutene over Isolated Hf Sites Grafted to Silicalite-1 and SiO2
Bell, Alexis T.,Lu, Peng,Lund, Alicia,Qi, Liang,Zhang, Yanfei
, p. 8352 - 8366 (2021/06/27)
Isolated hafnium (Hf) sites were prepared on Silicalite-1 and SiO2 and investigated for acetone conversion to isobutene. Characterization by IR, 1H MAS NMR, and UV-vis spectroscopy suggests that Hf atoms are bonded to the support via three O atoms and have one hydroxyl group, i.e, (SiO)3Hf-OH. In the case of Hf/Silicalite-1, Hf-OH groups hydrogen bond with adjacent Si-OH to form (SiO)3Hf-OH···HO-Si complexes. The turnover frequency for isobutene formation from acetone is 4.5 times faster over Hf/Silicalite-1 than Hf/SiO2. Lewis acidic Hf sites promote the aldol condensation of acetone to produce mesityl oxide (MO), which is the precursor to isobutene. For Hf/SiO2, both Hf sites and Si-OH groups are responsible for the decomposition of MO to isobutene and acetic acid, whereas for Hf/Silicalite-1, the (SiO)3Hf-OH···HO-Si complex is the active site. Measured reaction kinetics show that the rate of isobutene formation over Hf/SiO2 and Hf/Silicalite-1 is nearly second order in acetone partial pressure, suggesting that the rate-limiting step involves formation of the C-C bond between two acetone molecules. The rate expression for isobutene formation predicts a second order dependence in acetone partial pressure at low partial pressures and a decrease in order with increasing acetone partial pressure, in good agreement with experimental observation. The apparent activation energy for isobutene formation from acetone over Hf/SiO2 is 116.3 kJ/mol, while that for Hf/Silicalite-1 is 79.5 kJ/mol. The lower activation energy for Hf/Silicalite-1 is attributed to enhanced adsorption of acetone and formation of a C-C bond favored by the H-bonding interaction between Hf-OH and an adjacent Si-OH group.
