Highly Selective Catalytic Properties of HZSM-5 Zeolite in the Synthesis of Acetyl Triethyl Citrate by the Acetylation of Triethyl Citrate with Acetic Anhydride

Abstract

Abstract:The catalytic activities of acid catalysts for the acetylation of triethyl citrate with acetic anhydride in the preparation of acetyl triethyl citrate were evaluated. Microporous zeolites such as HZSM-5 and HY zeolites catalysts were introduced as heterogeneous acid catalysts. HZSM-5 zeolite catalysts showed a high conversion of triethyl citrate and excellent selectivity of acetyl triethyl citrate. The catalytic activities of HZSM-5 zeolites were superior to those of the HY zeolites. In particular, the selectivity of acetyl triethyl citrate on HZSM-5 zeolites exceeded 95%. The moderate acid strength of HZSM-5 (Si/Al = 75) zeolite led to the highest catalytic activities among the HZSM-5 zeolite catalysts, which have various acid strengths.

Niclosamide encapsulated in mesoporous silica and geopolymer: A potential oral formulation for COVID-19

“…Compared to the MCM-41 and SBA-15 (only one weak broad peak at 100–150 °C) [ [44] , [45] , [46] ], PG exhibited four desorption peaks: the first one 163 °C (weak acid sites), the second and third peaks at 321 and 378 °C (intermediate acidic sites) and the last peak at 604 °C (strong acid sites), indicating that the acidic property and the number of acid sites are increased with extra Al content in the PG framework. Similar phenomenon could be observed in the case of zeolite [ 47 ]. Therefore, this extra Al content in the PG makes them very special as a charged porous material, which can be further utilized for loading both charged and neutral drug molecules for various biomedical purposes.…”

Developments of biobased plasticizers for compostable polymers in the green packaging applications: A review

“…On the other hand, ATBC is mainly produced from TBC via two methods: direct esterification in the presence of acetic acid 54 and acetylation in the presence acetic anhydride 55 . Currently, different trademarks are already available in the global market, for example, Citroflex A‐2 and Citroflex A‐4, both widely used in different applications including food contact applications 56 . Each type possesses unique properties, for example, ATBC has good thermal stability, light, and water resistance and also maintains food flexibility at low temperature, 46 and shows a greater enhancement in cellulose nitrate films including better adhesion to metals, better resistance to yellowing and lower volatility compared to di‐butyl phthalate 56 .…”

“…Currently, different trademarks are already available in the global market, for example, Citroflex A‐2 and Citroflex A‐4, both widely used in different applications including food contact applications 56 . Each type possesses unique properties, for example, ATBC has good thermal stability, light, and water resistance and also maintains food flexibility at low temperature, 46 and shows a greater enhancement in cellulose nitrate films including better adhesion to metals, better resistance to yellowing and lower volatility compared to di‐butyl phthalate 56 . TBC has flame retardant and antibacterial properties, which shows remarkable plasticization efficiency 46 .…”

Efficient and selective glycerol electrolysis for the co-production of lactic acid and hydrogen with multi-component Pt/C-zeolite catalyst

“…NH 3 -TPD measurements were used to determine the total acid site concentration of the CBV600 catalysts. The Lewis acid site density calculated from the NH 3 desorption at 100 • C is 291 µmol g −1 , slightly lower than previously reported values due to the low temperature chosen here [39,40]. As a comparison, the surface acidity of the carbon black was also measured and calculated to be 18 µmol g −1 , which is negligible compared to CBV600.…”