Hydrogenation of Sodium Oleate in Aqueous Emulsion with the Hoveyda–Grubbs Second-Generation Catalyst

Abstract

The catalytic hydrogenation of sodium oleate in emulsion form was carried out using the second-generation Ru Hoveyda–Grubbs catalyst in a semibatch reactor. A fast and complete hydrogenation of the CC bond was observed after a reaction time of 1 h with 0.4 wt % catalyst at 120 °C and 8.27 MPa hydrogen gas. 1H NMR characterization shows that the carboxylic group CO was preserved without any reduction. The hydrogenated product sodium stearate was thus obtained. Our results show that the Hoveyda–Grubbs second-generation catalyst can maintain its activity for the hydrogenation reactions in an organic solvent free environment. The hydrogenation reaction presented here provides an alternate pathway to manufacture sodium stearate and other saturated fatty acid salts in a greater volume by an environmental friendly “green” process. In addition, this research will benefit the commercial process of catalytic hydrogenation of unsaturated elastomers in latex form.

Synthesis, Micellization, and Surface Activity of Novel Linear‐Dendritic Carboxylate Surfactants

“…Compared to the 1 H NMR spectra of C 18 ‐G 1 ‐(OH) 2 and C 18 ‐G 2 ‐(OH) 4 , the presence of two new peaks at 2.3–2.5 ppm for C 18 ‐G 1 ‐(COONa) 2 and C 18 ‐G 2 ‐(COONa) 4 may give the indication of the conversion from the hydroxyl group into carboxylate group. Carboxylate and ester groups make two CH 2  groups in the linkage have different chemical environments (Satyarthi et al, 2009; Wang et al, 2016), leading to two different 1 H NMR peaks at 2.3–2.5 ppm. Moreover, the ratios of peak areas at about 0.88, 1.06, and 2.3–2.5 ppm of C 18 ‐G 1 ‐(COONa) 2 and C 18 ‐G 2 ‐(COONa) 4 are in well agreement with their linear‐dendritic structures.…”

Continuous and Electrochemical Synthesis of 2,2’,4,4’,6,6’‐Hexanitrostilbene

“…However, many by-products (HNBB) are obtained in this method, and the solvent (DMSO) used is difficult to handle in the post-treatment process. [20,21] Electrochemical synthesis is a promising alternative to traditional synthesis involving chemical oxidants and reductants because it obviates the use of dangerous and toxic reagents. [22][23][24][25] Thus far, electrochemical synthesis has been successfully applied to various energetic materials synthesis processes such as nitration, coupling, and dehydrogenation.…”

“…To solve this problem, Lu chose TEMPO‐FeCl 2 as the dehydrogenation agent, which greatly improved the reaction yield (the current highest yield, 70 %) and provided good repeatability. However, many by‐products (HNBB) are obtained in this method, and the solvent (DMSO) used is difficult to handle in the post‐treatment process [20,21] …”

One‐step Synthesis of End‐Functionalized Hydrogenated Nitrile‐Butadiene Rubber by Combining the Functional Metathesis with Hydrogenation

“…However, the HNBR produced has a high viscosity relatively to the molecular mass of the macromere due to the limitation of the current production technology and natural aging of nitrile‐butadiene rubber during storage . This seriously affects its processing performance and restricts its widespread application . The olefin metathesis reaction is a valuable new method to prepare moderate molecular weight HNBR …”

“…[33] This seriously affects its processing performance and restricts its widespread application. [34] The olefin metathesis reaction is a valuable new method to prepare moderate molecular weight HNBR. [35][36][37][38][39][40] In the ongoing studies on the chemical modification of NBR by metathesis reaction, methyl methacrylate (MMA) is a valuable functional monomer to modify the molecular structure of NBR during hydrogenation.…”