Haifeng Liu

Bio: Haifeng Liu is an academic researcher from Chinese Academy of Sciences. The author has contributed to research in topics: Catalysis & Transesterification. The author has co-authored 2 publications.

Using waste crayfish shell derived catalyst to synthesize glycerol carbonate by transesterification reaction between glycerol and dimethyl carbonate

Abstract: Waste crayfish shell powder was utilized to prepare a series of solid base catalyst for the transesterification of glycerol with dimethyl carbonate to synthesize glycerol carbonate Thermal decomposition behavior of waste crayfish shell powder was investigated by thermogravimetric analysis (TGA) and the different catalysts prepared at different calcinations temperature were characterized using FESEM, XRD, FTIR, BET techniques It was clearly confirmed that the catalyst generated by the calcination of waste crayfish shell at 800 °C exhibited excellent catalytic activity, 987% glycerol conversion and 953% glycerol carbonate yield were obtained under mild reaction conditions such as 90 min of reaction time, 1:6 molar ratio of glycerol to dimethyl carbonate, 4 wt% of catalyst loading and 75 °C of reaction temperature

One-pot facile synthesis of PDMS/PDMAEMA hybrid sponges for surfactant stabilized O/W emulsion separation.

Abstract: Hydrophobic/oleophilic sponges are excellent absorbent materials for oil contaminant removal. However, the application is limited in dealing with surfactant stabilized O/W emulsions. The water in the emulsion isolates the contact between the sponge and oil droplets. Consequently, the oil absorption efficiency is not ideal. Herein, to improve the oil absorption efficiency from anionic surfactant stabilized O/W emulsions, water responsive hybrid sponges were reported. To prepare such sponges, water soluble poly(N,N-dimethylaminoethylmethacrylate) (PDMAEMA) was introduced into polydimethylsiloxane (PDMS) sponges using table salt as a template and multi-walled carbon nanotubes (MWCNTs) as mechanical reinforcement in a one-pot method. Upon contact with an O/W emulsion, the water soluble PDMAEMA chain rose to the surface of the sponge, turning the hydrophobic surface into hydrophilic. Next, the tertiary amine groups in PDMAEMA ionized in water and carried positive charges which would cause the coagulation of oil droplets. Finally, the coagulated oil droplets were absorbed immediately by the oleophilic inner part of the sponge through the wicking effect. As a result, a Janus interface was generated in situ and sustained. Such material design synergistically contributed to a satisfactory hexadecane (HD) absorption efficiency of 178 ± 4% in 25 min. In contrast, the PDMS-MWCNT1.0% sponge could only absorb 9.8 ± 0.2% HD. Moreover, these sponges also presented robust mechanical performance and reusability, offering a new route for oil/water separation and oil pollution remediation in open water.

Recent Advances in Conversion of Glycerol: A Byproduct of Biodiesel Production to Glycerol Carbonate

Abstract: Owing to erupted ecological concerns and escalated energy consumption, biodiesel produced by transesterifying nonedible and used cooking oils has been acknowledged as a viable source of clean and sustainable energy, alternative to fossil fuels. This transesterification process led to an excessive supply of glycerol as the primary byproduct which can then be transformed into value-added derivatives, primarily glycerol carbonate (GC), thereby drawing attention to its potential use in industrial applications. Although several methods for synthesis of GC utilize glycerol as building block, the transesterification approach using dimethyl carbonate (DMC) is the most effective route implementing safer and greener reaction conditions. This review is focused on different types of heterogeneous catalysts and characterization techniques used for identifying and deactivating those catalysts, covering the literature from the last decade to till date on this topic. Potent applications of GC as a versatile compound are elucidated in brief. Finally, a conclusion, outlook, and author’s perspective have been provided in brief.