Electrochemical hydrogenation of soybean oil by filling H ₂ in supercritical CO ₂

Abstract

Electrochemical hydrogenation under a mixed gas environment of CO2 and H2 was studied. It was found that in supercritical CO2 (SC‐CO2), the mole fraction of H2 in both the CO2 and electrolytes increased as H2 pressure increased. CO2 was dissolved in the electrolyte to form unstable carbonic acid, which was easily decomposed into HCO3- and H+. Meanwhile, H2 was electrolyzed to form H+ at the anode, so that the conductivity increased, the hydrogen consumption of the reaction increased, and then tended to be stable at a total pressure of 9.0 MPa. Herein, the electrochemical hydrogenation of soybean oil was accomplished at a current of 120 mA, a temperature of 50°C, and an agitation speed of 300 rpm. The iodine value (IV) of the hydrogenated soybean oil was 90.6 g I2/100 g oil at 7 hr and the trans fatty acid (TFA) content in the oil was 3.32%. Practical applications In the present study, H2 was added to the electrochemical hydrogenation reactor and soybean oil was electrochemically hydrogenated by filling H2 in supercritical CO2. By filling H2, the TFAs of the hydrogenated soybean oil were reduced, and the TFA content was only 3.32%. The reaction rate of the hydrogenation was faster and the hydrogenation time decreased by 5 hr compared with the hydrogenation of soybean oil at a normal pressure. Moreover, the electrochemical hydrogenation reactor used a moderate pressure and a large reaction volume, which is beneficial to industrialization. The electrochemical hydrogenation by filling H2 in SC‐CO2 decreased the hydrogenation time and reduced the industrial production costs. This method can be further applied for industrial purposes.

The Effect of a Low Degree of Fluorine Substitution on Cotton Fiber Properties

“…[ 2b,6–8 ] A DS value of 0.006 is similar to that found for the chemical esterification of starch by octenyl succinic ester (OSA ester) (DS = 0.006). [ 9 ]…”

Supercritical electrocatalytic catalyst activation and its application in safflower seed oil isomerisation to prepare conjugated linoleic acid

“…(2017) and Wang et al . (2019), electrocatalytic treatment has already been applied to edible oil. Additionally, supercritical CO 2 has been confirmed to be nontoxic, inexpensive, and easily separated and has been widely used in the food industry.…”

“…Regarding health, according to List et al (2007), Yu et al (2017) and Wang et al (2019), electrocatalytic treatment has already been applied to edible oil.…”

“…Yu et al (2017) found that compared with the conventional hydrogenation process, the reaction time was shortened by 4 h, and the TFA content was reduced by 35.8% for supercritical electrochemical hydrogenation of soybean oil. Wang et al (2019) demonstrated that supercritical CO 2 could effectively improve the electrolysis effect of electrochemical reactions, accelerate the catalytic rate and reduce the catalytic time. However, the application of electrocatalytic and supercritical CO 2 treatment in catalyst activation is rare.…”

“…Wang et al . (2019) demonstrated that supercritical CO 2 could effectively improve the electrolysis effect of electrochemical reactions, accelerate the catalytic rate and reduce the catalytic time. However, the application of electrocatalytic and supercritical CO 2 treatment in catalyst activation is rare.…”