Technological Parameters of Epoxidation of Sesame Oil with Performic Acid

Abstract

The course of epoxidation of sesame oil (SO) with performic acid formed „in situ” by the reaction of 30 wt% hydrogen peroxide and formic acid in the presence of sulfuric acid(VI) as a catalyst was studied. The most advantageous of the technological independent parameters of epoxidation are as follows: temperature 80°C, H2O2/ C=C 3.5:1, HCOOH/C=C 0.8:1, amount of catalyst as H2SO4/(H2O2+HCOOH) 1 wt%, stirring speed at least 700 rpm, reaction time 6 h. The iodine number (IN), epoxy number (EN), a relative conversion to oxirane (RCO) and oxirane oxygen content (EOe) were determined every hour during the reaction. Under optimal conditions the sesame oil conversion amounted to 90.7%, the selectivity of transformation to epoxidized sesame oil was equal to 93.2%, EN = 0.34 mol/100 g, IN = 0.04 mol/100 g oil (10.2 g/100 g oil), a relative conversion to oxirane RCO = 84.6%, and oxirane oxygen content of EOe = 5.5%.

Catalytic developments in the epoxidation of vegetable oils and the analysis methods of epoxidized products

“…18 Vegetable oils including edible, non-edible, and waste cooking oils can be transformed into valuable epoxides by the conventional homogeneous system (current industrial process), in which peracids such as performic acid, peracetic acid, and perpropanoic acid are chosen as oxygen carriers in the presence of H 2 O 2 and inorganic acid catalysts (H 2 SO 4 , H 3 PO 4 , and HNO 3 ). [19][20][21][22][23][24][25][26] The degradation of oxirane ring as the undesirable side reaction caused by water, hydrogen peroxide, acetic acid, and peracetic acid was studied in detail for the liquid-liquid system. As a result, acid hydrolysis of epoxidized EVOs happens very slowly but degradation of the oxirane ring by H 2 O 2 in the presence of acid is fast.…”

Preparation of Bio-Based Polyurethane Coating from Citrullus colocynthis Seed Oil: Characterization and Corrosion Performance

“…The final product was then washed with water and extracted with petroleum ether. Then, petroleum ether was removed in a rotary evaporator [ 16 , 27 ]. The conversion (%), epoxidation (%), and selectivity (%) of the produced epoxidized oil were calculated as described in the literature [ 28 , 29 ].…”

Epoxidation of crambe seed oil with peracetic acid formed in situ

“…Although the reaction conducted with 3 wt% catalyst had a faster rate of epoxide formation at the beginning of the process, after 8 h, there was a slight decline in the curve. The decrease in epoxy numbers is caused by side reactions due to the opening of the oxirane rings, mainly in the reaction of water with carboxylic acid, resulting in the formation of glycols and hydroxyl formats, which was intensified at higher concentrations of H 2 SO 4 (Musik et al, 2018). Mungroo et al (2008) mentions a relation between the formation of glycol through the opening of the oxirane ring with the decrease in the yield of epoxides, indicating that this compound is directly linked to the instability of the oxirane ring.…”