Catalysis of Epoxidation & Ring Cleavage Reactions by Ionic Resins

INQUIRY

Introduction

The selective epoxidation of soybean oil by performic acid can be used to illustrate the application of ionic resin catalyst in the epoxidation reaction.Under the catalysis of inorganic acids such as sulfuric acid and phosphoric acid, carboxylic acid and hydrogen peroxide will react in situ to form peracid. This reaction takes place in the water phase, but after the peracid is generated, it will migrate from the water phase to the oil phase, and quickly react with the double bonds of the oil molecules to produce ethylene oxide products. At this step, carboxylic acid will be produced at the same time, and the newly produced carboxylic acid will return to the water phase and start the catalytic cycle. However, in the entire reaction process, the inorganic acid catalyst promotes side reactions, such as ethylene oxide ring opening, resulting in a sharp drop in product selectivity. In addition, the inorganic acid catalyst needs to be neutralized with alkali (such as NaOH) at the end of the reaction. However, the alkaline environment is conducive to the hydrolysis of triglycerides, forming substances that have a negative impact on the quality of the desired product.

Fig.1 Images of two resins after epoxidation run( Turco R, et al., 2013)

Camphene is an intermediate compound of commercial chemicals such as isobornyl, isobornyl acetate and camphor. The traditional production process of camphene mainly uses acidic TiO2 catalyst to isomerize α-pinene. The use of the catalyst has problems such as preparation, reproducibility, and relatively long time to recover the catalyst from the product after α-pinene isomerization. Using ion exchange resin to replace TiO2, it is found that the similar catalytic effect can be achieved by adjusting the temperature and the ratio of α-pinene/catalyst, and the problem of catalyst recovery can also be solved.(Chimal Valencia O, et al.,2004)

As an expert in the field of ionic resin and organic synthesis, Alfa Chemistry focuses on the application of ionic resin catalysts in organic synthesis. We provide various types of ionic resin catalysts, which can be used in a variety of organic reactions. Our goal is to help you speed up the synthesis process and provide customized resins. Our customers can directly contact our experts and provide timely feedback on any online inquiries. If you are interested in our services, please Ionic resin as a heterogeneous catalyst can minimize side reactions and increase selectivity. Acidic resins are characterized by the presence of strong isolated acidic sites located inside the pore structure. These sites are not easily approached by large oil molecules containing ethylene oxide rings, so they can prevent reactions with protons. For gel-type ionic resins, the higher the degree of cross-linking of the resin, the fewer pores after swelling, and the lower the probability of contact with oil molecules, so it will exhibit higher selectivity. Macroporous ionic resins can solve the shortcomings of reactor blockage. Invariably, ionic resins have high selectivity and high conversion rates for epoxidation reactions, and it is not an exaggeration to be called the best acid catalyst.

Reference

Turco R, et al. Selective epoxidation of soybean oil with performic acid catalyzed by acidic ionic exchange resins[J]. Green Processing and Synthesis, 2013.