scholarly journals A Porous Polymer-Based Solid Acid Catalyst with Excellent Amphiphilicity: An Active and Environmentally Friendly Catalyst for the Hydration of Alkynes

Polymers ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 2091 ◽  
Author(s):  
Yizhu Lei ◽  
Maomin Zhang ◽  
Qian Li ◽  
Yu Xia ◽  
Guojun Leng

Developing efficient solid acid catalysts for aqueous organic reactions is of great importance for the development of sustainable chemistry. In this work, a porous polymeric acid catalyst was synthesized via a solvothermal copolymerization and a successive ion-exchange method. Physicochemical characterizations suggested that the prepared polymers possessed large Brunauer-Emmett-Teller (BET) surface areas, a hierarchically porous structure, excellent surface amphiphilicity, and nice swelling properties. Notably, an activity test in phenylacetylene hydration indicated that the prepared solid acid exhibited high catalytic activity in water, which outperformed commercial amberlyst-15, sulfuric acid, and benzenesulfonic acid. Moreover, the prepared solid acid can be easily recovered and reused at least four times. Additionally, a variety of aromatic and aliphatic alkynes could be effectively transformed into corresponding ketones under optimal reaction conditions.

2018 ◽  
Vol 156 ◽  
pp. 03002
Author(s):  
Iwan Ridwan ◽  
Mukhtar Ghazali ◽  
Adi Kusmayadi ◽  
Resza Diwansyah Putra ◽  
Nina Marlina ◽  
...  

The oleic acid solubility in methanol is low due to two phase separation, and this causes a slow reaction time in biodiesel production. Tetrahydrofuran as co-solvent can decrease the interfacial surface tension between methanol and oleic acid. The objective of this study was to investigate the effect of co-solvent, methanol to oleic acid molar ratio, catalyst amount, and temperature of the reaction to the free fatty acid conversion. Oleic acid esterification was conducted by mixing oleic acid, methanol, tetrahydrofuran and Amberlyst 15 as a solid acid catalyst in a batch reactor. The Amberlyst 15 used had an exchange capacity of 2.57 meq/g. Significant free fatty acid conversion increments occur on biodiesel production using co-solvent compared without co-solvent. The highest free fatty acid conversion was obtained over methanol to the oleic acid molar ratio of 25:1, catalyst use of 10%, the co-solvent concentration of 8%, and a reaction temperature of 60°C. The highest FFA conversion was found at 28.6 %, and the steady state was reached after 60 minutes. In addition, the use of Amberlyst 15 oleic acid esterification shows an excellent performance as a solid acid catalyst. Catalytic activity was maintained after 4 times repeated use and reduced slightly in the fifth use.


2011 ◽  
Vol 306-307 ◽  
pp. 1508-1511
Author(s):  
Sheng Huan Liu ◽  
Ping Rui Meng ◽  
Li Juan Yu ◽  
Yan Mei Zhang ◽  
Xiao Hui Wang

Styrene/Sodium allyl sulfonate copolymer (St-c-SAS) were prepared using soap-free emulsion polymerization method and boiling at high-speed stirring, and it was acided to obtain an efficient, stable, reusable new solid acid catalyst styrene/acrylic acid copolymer (St-c-AS). Elemental analysis and acid–base titration techniques showed that St-c-AS have high concentration of sulfonic groups. Differential thermal analysis (DTA) and thermogravimetric analysis (TG) results showed that the sulfonic of copolymer was hard to fall off at high temperature. Esterifications of acetic acid with ethanol showed that St-c-AS has high catalytic activity, and the catalyst can be reused without separation of 10 times, the esterification yields close to or exceed 100%. The superior performance of St-c-AS is attributed to their unique features including large surface area, high content of sulfonic groups as well as high temperature resistance.


2016 ◽  
Vol 79 (1) ◽  
Author(s):  
Nur Aainaa Syahirah Ramli ◽  
Nur Hidayah Zaharudin ◽  
Nor Aishah Saidina Amin

Levulinic acid (LA) is a versatile biomass-derived building block as it can be used for the synthesis of organic chemicals as alternative to the depleting fossil fuel resources. Levulinate esters, obtained from catalytic esterification of LA with alcohol, can be used in many applications such as fragrance and fuel additives. In this study, ion-exchange resins Amberlyst-15 was employed as solid acid catalyst for esterification of LA with methanol for methyl levulinate (ML) production. The effect of reaction time, catalyst loading, and molar ratio of LA to methanol, was investigated on LA esterification to ML at the reflux condition. The optimum ML yield of 82% was obtained from reaction conducted at reflux temperature for 5h, using 30% of Amberlyst-15 loading, and 1:20 of LA to methanol molar ratio. The reusability of Amberlyst-15 for ML production was examined for five successive reactions. In addition, Amberlyst-15 catalyst, employed in the esterification of LA with ethanol and 1-butanol for ethyl levulinate (EL) and butyl levulinate (BL), respectively, registered good performance. Yields of 71% and 55% have been obtained for EL and BL, respectively. Amberlyst-15 is a promising solid acid catalyst for production of biomass derived levulinate esters at mild process conditions. 


2019 ◽  
Vol 4 (48) ◽  
pp. 14315-14328 ◽  
Author(s):  
Tusar Kanto Dey ◽  
Piyali Bhanja ◽  
Priyanka Basu ◽  
Aniruddha Ghosh ◽  
Sk. Manirul Islam

Synthesis ◽  
2021 ◽  
Author(s):  
Ken-ichi Itoh ◽  
Mamiko Hayakawa ◽  
Rina Abe ◽  
Shinji Takahashi ◽  
Kenta Hasegawa ◽  
...  

Nitrile oxides were obtained from α-nitro ketones by the use of silica-gel supported sodium hydrogensulfate (NaHSO4/SiO2) or Amberlyst 15 as solid acid catalyst, and then the corresponding 3-acylisoxaszoles were obtained from alkynes via the 1,3-dipolar ([3+2]) cycloaddition. These heterogeneous catalysts are easily separable from the reaction mixture, and reused up to the synthesis. This synthetic method provides a facile, efficient and reusable production of 3-acylisoxazoles.


2020 ◽  
Vol 20 (6) ◽  
pp. 3496-3503
Author(s):  
Shuang Wang ◽  
Ling Wan ◽  
Leizhi Zheng ◽  
Xiaoqi Fu ◽  
Tingshun Jiang ◽  
...  

We present here a facile synthesis of SO2-4/ZrO2 solid superacid by impregnating the biscuit-like mesoporous ZrO2 nanoparticles prepared by an emulsion combustion method directly into H2SO4 solution. The obtained solid acid catalyst was characterized by means of X-ray powder diffraction, transmission and scanning electron microscopy, thermogravimetry, Brunner-Emmet-Teller measurement, and infrared analysis. Its catalytic performance was examined by alkylation of o-xylene with styrene. The optimal catalytic formulation, obtained from the investigation of experimental conditions, was determined to be 5 wt% of catalyst loading with initial o-xylene/styrene molar ratio of 5 under reaction temperature at 120 °C for 120 min, achieving a 100% styrene conversion and a 93.3% 1-phenyl-1-xylyl ethane selectivity. The biscuit-like SO2−4/ZrO2 solid acid exhibited high catalytic activity and selectivity and excellent structural stability. This synthetic strategy for preparing the mesoporous SO2−4 promoted ZrO2 solid superacid catalyst is generalized and expected to be applied to other metal oxides.


2012 ◽  
Vol 550-553 ◽  
pp. 234-237 ◽  
Author(s):  
Jun Ping Zhuang ◽  
Xue Ping Li ◽  
Ying Liu

Biomass represents an abundant and relatively low cost carbon resource that can be utilized to produce platform chemicals such as levulinic acid. This study focused on the effect of SO42-/TiO2-Al2O3-SnO2solid acid catalyst on the catalytic performance in levulinic acid production from biomass-derived carbohydrates glucose. The SO42-/TiO2-Al2O3-SnO2solid acid catalyst showed a high catalytic activity for the selective conversion of glucose to levulinic acid. Experimental results showed that SO42-/TiO2-Al2O3-SnO2solid acid had markedly catalytic effects on the conversion of glucose to levulinic acid. With SO42-/TiO2-Al2O3-SnO2solid acid as the catalyst, an optimized ethyl levulinic acid was obtained at 180 °C for 2 h with glucose dosage of 2 wt% and 3 g SO42-/TiO2-Al2O3-SnO2solid acid catalys and the levulinic acid yield was 74.05%.


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