Synthesis of methyl glycolate via low-temperature hydrogenation of dimethyl oxalate over an efficient and stable Ru/activated carbon catalyst

BACKGROUND Syngas to dimethyl oxalate (DMO) followed by hydrogenation to methyl glycolate (MG) is considered to be an environmentally friendly and economical route. However, the catalyst with super performance and low cost for this route is still challenging. In this work, a simple and low-lost fabrication method was developed to prepare a Ru/activated carbon (AC) catalyst and was used for DMO hydrogenation to MG under mild reaction conditions. RESULTS The Ru/AC catalyst showed the best performance in the low-temperature hydrogenation of DMO to MG compared to Ru/SiO2 and Ru/Al2O3. A series of characterization results showed that the super catalytic properties of Ru/AC catalyst might be attributed to the higher dispersion of Ru on support and its smallest nanoparticles size, weak surface acidity and electron-deficient state of Ru species. The key parameters such as Ru loading, temperature, weight hourly space velocity, and pressure, were comprehensively investigated. MG selectivity of 94.6% with DMO conversion of 97.2% were obtained over the 4.0 Ru/AC catalyst at 90 degrees C. The 4.0Ru/AC catalyst showed excellent stability and there was no obvious deactivation after 1032 h test. CONCLUSIONS The Ru/AC catalyst is effective for the DMO hydrogenation to MG under mild conditions and has great promise for industrial applications because of its low cost, simple preparation, high efficiency, and long life. (c) 2022 Society of Chemical Industry (SCI).

Automated summary

A simple and low-cost Ru/activated carbon (AC) catalyst was developed for the hydrogenation of dimethyl oxalate (DMO) to methyl glycolate (MG) under mild conditions. The Ru/AC catalyst demonstrated superior catalytic performance, which could be attributed to its high dispersion of Ru, small particle size, weak surface acidity, and electron-deficient state of Ru species.