Decomposition of lignin model compounds by Lewis acid catalysts in water and ethanol

Preparation of magnetic silica supported Brönsted acidic ionic liquids for the depolymerization of lignin to aromatic monomers

Lignin, the most abundant renewable resource of aromatics in nature, is recognized as an alternative for fossil-based fuels and chemicals. Herein, we proposed an efficient method to obtain aromatic monomers...

Extraction of Vanillin Following Bioconversion of Rice Straw and Its Optimization by Response Surface Methodology

Value-added chemicals, including phenolic compounds, can be generated through lignocellulosic biomass conversion via either biological or chemical pretreatment. Currently vanillin is one of the most valuable of these products that has been shown to be extractable on an industrial scale. This study demonstrates the potential of using rice straw inoculated with Serpula lacrymans, which produced a mixture of high value bio-based compounds including vanillin. Key extraction conditions were identified to be the volume of solvent used and extraction time, which were optimized using response surface methodology (RSM). The vanillin compounds extracted from rice straw solid state fermentation (SSF) was confirmed through LC-ESI MS/MS in selective ion mode. The optimum concentration and yield differed depending on the solvent, which was predicted using 60 mL ethyl acetate for 160 min were 0.408% and 3.957 μg g⁻¹ respectively. In comparison, when ethanol was used, the highest concentration and yields of vanillin were 0.165% and 2.596 μg g⁻¹. These were achieved using 40 mL of solvent, and extraction time increased to 248 min. The results confirm that fungal conversion of rice straw to vanillin could consequently offer a cost-effect alternative to other modes of production.

A review on high catalytic efficiency of solid acid catalysts for lignin valorization

It is imminent to develop renewable resources to replace fossil-derived energies as fossil resources are on the brink of exhaustion. Lignin is one of the major components of lignocellulosic biomass, which is a natural amorphous three-dimensional polymer with abundant C-O bonds and aromatic structure. Hence, valorization of lignin into high value-added liquid fuels and chemicals is regarded as a promising strategy to mitigate fossil resource shortages. Solid acid catalysts are extensively studied due to environmentally friendly in terms of the ease of separation, recovery and reduced amount of wastes. Hence, this review focuses on summarizing the recent progress of catalytic valorization of lignin over different kinds of solid acid catalysts including zeolites, heteropolyacids, metal oxides, amorphous SiO₂-Al₂O₃, metal phosphates, and Lewis acid. Based on reviewing of current progress of lignin conversion, the challenges and future prospects are emphasized.

Molecular behaviour of phenol in zeolite Beta catalysts as a function of acid site presence: a quasielastic neutron scattering and molecular dynamics simulation study

The dynamic behaviour of phenol in zeolite Beta is strongly influenced by the presence of Brønsted acid sites.