Application of Phase Transfer Catalysis in the Esterification of Organic Acids: The Primary Products from Ring Hydrocarbon Oxidation Processes

Abstract

For enhancing the cetane number (CN) of diesel fraction, the selective oxidative ring opening method was applied to upgrade ring hydrocarbons. Organic acids, one of the main products from this oxidative reaction, being esterified by the phase transfer catalysis (PTC) approach were studied. Adipic acid, benzoic acid, and phthalic acid were used as model compounds. Reaction time, reaction temperature, the amount of water, and the amount of catalyst in the esterification process were investigated and optimized using orthogonal experimental design method. The kinetics of esterification process was then conducted under the optimal condition. The types of catalysts and organic acids, the amount of catalyst and water were also investigated. The PTC esterification was one rate controlling reaction on the interface between the aqueous phase and the oil phase. Hydrophobicity is a key factor for converting benzoic acid, adipic acid, and phthalic acid to the corresponding esters. It was found that around 5–8% water is the optimal quantity for the given reaction system. Two cases of esterification processes of PTC were proposed.

Organo‐sulfonic acid catalyzed degradation kinetics and thermodynamic studies of nylon‐6 by hydrothermal method

“…It becomes supersaturated with PTC as the concentration increases, hence a decrease in degradation yield. [27][28][29] Another parameter investigated is the effect of acid solution concentration on nylon degradation, which is presented in Figure 5C. constant after a certain period, as seen in Figure 5C.…”

Accelerated Non-Enzymatic Fatty Acid Esterification during Microdroplet Collision: A Method for Enhanced Sustainability

“…SEs are used in several food, pharmaceutical, and cosmetic industries. ,− However, lipase-catalyzed esterification reactions are limited by the choice of the solvent system for making a homogeneous solution for lipids that are soluble in non-polar solvents and sugars soluble in water. To overcome the solution-phase heterogeneity, several ionic liquid-based synthetic protocols have been attempted in the past. − Use of a phase transfer catalyst is a general practice in such organic–aqueous mixed phase reactions …”

“…20−22 Use of a phase transfer catalyst is a general practice in such organic−aqueous mixed phase reactions. 23 Since the development of electrospray ionization-mass spectrometry (ESI-MS) half a century ago, it has facilitated the advancement of molecular analysis. In ESI, solution-phase neutral molecules are converted to gas phase ions via charged microdroplets.…”

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