2-Butyne-1,4-diol hydrogenation in supercritical CO2: Effect of hydrogen concentration

The solubility of H 2 in electrolytes, H 2 reaction consumption and the conductivity of electrolytes under different pressures in an electrochemical hydrogenation reactor were studied. It was found that with an increase in H 2 pressure, H 2 was electrolyzed at the anode, accompanied by the generation of H +. The solubility of H 2 in the electrolytes and the conductivity of the electrolytes also increased. At first, the reaction consumption increased, followed by a tendency to be stable at 3 MPa. Therefore, the electrochemical hydrogenation of soybean oil was carried out at a H 2 pressure of 3 MPa. When the current was 120 mA, the temperature was 50℃, the agitation speed was 300 rpm, and the time was 7.5 h, the IV of hydrogenated soybean oil was 99.6 g I 2 /100 g oil, and the TFA content of the oil was 4.3%.

show abstract

Section: Solubility and Consumption Of H 2 In The Electrolytesupporting

confidence: 93%

Study on the Electrochemical Hydrogenation of Soybean Oil under H<sub>2</sub> Conditions

et al. 2019

View full text Add to dashboard Cite

show abstract

“…At the saturation level, there was sufficient hydrogen to participate in the oil hydrogenation reaction at the maximum rate, and the hydrogen consumption no longer changed. This is consistent with the conclusion of Kriaa, Serin, Contamine, Cézac, and Mercadier (). In addition, the rate constant k 3 for the hydrogenation of trienoic acid was 0.0373, the rate constant k 2 for the hydrogenation of dienoic acid was 0.0079, and the rate constant k 1 for the hydrogenation of monoenoic acid was 0.0039.…”

Section: Resultssupporting

confidence: 93%

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

Wang

Geng

et al. 2019

J Food Process Preserv

View full text Add to dashboard Cite

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.

show abstract

“…Today, the Reppe process is the major route for the commercial manufacture of 1,4-butynediol (BD) [2,3]. Due to the numerous applications of chemicals derived from BD, such as 1,4-butanediol (BDO), 3-butene-1-ol (BTO), tetrahydrofuran (THF), poly(tetramethylene ether) glycol (PTMEG), γ-butyrolactone (GBL), and poly(butylene succinate) (PBS), among others [4][5][6], which are in high demand in the chemical, polymer, pharmaceuticals, and textiles industries [7][8][9][10][11], the design of highly efficient ethynylation catalysts for the synthesis of BD is of great significance.…”

Section: Introductionmentioning

confidence: 99%

Enhancing the Ethynylation Performance of CuO-Bi2O3 Nanocatalysts by Tuning Cu-Bi Interactions and Phase Structures

et al. 2019

View full text Add to dashboard Cite

Catalytic systems consisting of copper oxide and bismuth oxide are commonly employed for the industrial production of 1,4-butynediol (BD) through ethynylation. However, few studies have investigated the influence mechanism of Bi for these Cu-based catalysts. Herein, a series of nanostructured CuO-Bi2O3 catalysts were prepared by co-precipitation followed by calcination at different temperatures. The obtained catalysts were applied to the ethynylation reaction. The textural and crystal properties of the catalysts, their reduction behavior, and the interactions between copper and bismuth species, were found to strongly depend on temperature. When calcined at 600 °C, strong interactions between Cu and Bi in the CuO phase facilitated the formation of highly dispersed active cuprous sites and stabilized the Cu+ valency, resulting in the highest BD yield. Bi2O3 was completely absent when calcined at 700 °C, having been converted into the spinel CuBi2O4 phase. Spinel Cu2+ was released gradually to form active Cu+ species over eight catalytic cycles, which continuously replenished the decreasing activity resulting from the formation of metallic Cu and enhanced catalytic stability. Moreover, the positive correlation between the in-situ-formed surface Cu+ ions and BD yield suggests that the amount of Cu+ ions is the key factor for ethynylation of formaldehyde to BD on the as prepared CuO-Bi2O3 catalysts. Based on these results and the literature, we propose an ethynylation reaction mechanism for CuO-based catalysts and provide a simple design strategy for highly efficient catalytic CuO-Bi2O3 systems, which has considerable potential for industrial applications.

show abstract

2-Butyne-1,4-diol hydrogenation in supercritical CO2: Effect of hydrogen concentration

Cited by 12 publications

References 29 publications

Study on the Electrochemical Hydrogenation of Soybean Oil under H<sub>2</sub> Conditions

Study on the Electrochemical Hydrogenation of Soybean Oil under H<sub>2</sub> Conditions

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

Enhancing the Ethynylation Performance of CuO-Bi2O3 Nanocatalysts by Tuning Cu-Bi Interactions and Phase Structures

Contact Info

Product

Resources

About

2-Butyne-1,4-diol hydrogenation in supercritical CO2: Effect of hydrogen concentration

Cited by 12 publications

References 29 publications

Study on the Electrochemical Hydrogenation of Soybean Oil under H<sub>2</sub> Conditions

Study on the Electrochemical Hydrogenation of Soybean Oil under H<sub>2</sub> Conditions

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

Enhancing the Ethynylation Performance of CuO-Bi2O3 Nanocatalysts by Tuning Cu-Bi Interactions and Phase Structures

Contact Info

Product

Resources

About

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