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Bioenergy is a key strategy for sustainability, yet the potential for biofuel production from chitin is under-exploited. Here, we report the cleavage of the inherently inert σ-type C–C bonds in chitin under the condition of initially breaking the unstable C–O bonds. Mechanistic studies indicate that by regulating the valence state of Ru and the interaction between RuOx and AC-HNO3-melamine, the ability of Ru nanoparticles to cleave C–C and C–O bonds can be controlled. One-pot sequential hydrogenolysis of chitin with RuOx/AC-HNO3-melamine resulted in a mixed alcohol yield 1.66 times that of commercial Ru/C. A mixed alcohol yield of 16.8% was achieved using raw chitin and green process conditions. We expanded the substrate range to include chitosan, N-acetyl- D -glucosamine, and glucosamine. This work demonstrates the potential of shell biorefinery to produce affordable clean energy. [ABSTRACT FROM AUTHOR]

Lignin, a renewable aromatic polymer, has great potential as a synthetic building block for functional materials. The effects of quaternary ammonic methylation of alkali lignin (AL) on the morphologies and ofloxacin antibiotic (OA) removal application from water are investigated by using the dissipative particle dynamics (DPD) simulation method. Untreated AL can form spherical aggregates, but the phenylpropane units of untreated AL and loaded broad‐spectrum OA molecules are randomly distributed in aggregates. However, if quaternary ammonic groups are grafted onto all orthopositions of the phenolic hydroxyl groups (100‐QAMAL), then multilamellar spherical aggregates are obtained and OA molecules are entrapped in the aggregates. To prepare multilamellar spherical aggregates with an ordered and regular layered structure, <15 v% of 100‐QAMAL and low molecular weights of AL (≈4700–9400 Da) are suggested to be used. Lignin‐based multilamellar spherical aggregates can be adopted as potential functional carriers for removing pollutant OA from water. [ABSTRACT FROM AUTHOR]

Integrated carbon capture and utilization (ICCU) simplifies the CO2 utilization process by converting chemically combined CO2 molecules into value-added chemicals, leading to a strong energy-saving effect by omitting the CO2 separation process. Two reaction routes for the hydrogenation of amine captured CO2 to methanol over heterogeneous catalysts were summarized: alcoholic hydroxyl groups-promoted CO2 hydrogenation process over Cu or Pd-based catalysts via formate and ester route, and methanol production from the direct hydrogenation of formate over Au-based catalyst. The technical effectiveness of concurrent carbon capture with heterogeneous catalysis toward methanol via alcoholic hydroxyl groups-promoted CO2 hydrogenation is similar to that of the gas-phase CO2 hydrogenation to methanol over heterogeneous catalysts. The sintering of the catalysts, the phase change of the supports, the combination of amines and the catalysts (namely leaching), and the reaction of water with the supports can cause a decrease in the performance of the catalysts. Thus, it is important to rationally design next-generation stable catalysts to achieve amine captured CO2 hydrogenation to methanol while at the same time regenerating amines. The development of heterogeneous catalysts for methanol synthesis in the liquid phase and the development of the CO2 capture process for subsequent conversion(1 ~ 70%) were carefully reviewed. The integration and optimization of multi-pollutant efficient removal technology, selectively coupled CO2 capture technology, and selective routes for methanol synthesis can achieve industrial verification in typical power plants, which is of great significance in promoting energy conservation, emission reduction, and low-carbon footprint. [ABSTRACT FROM AUTHOR]

The development of safe, low-cost and highly active non-precious metal electrocatalysts plays a vital role in efficient hydrogen production. Herein, Mo2C/Mo2N heterostructure was in-situ synthesized by a two-step method for excellent hydrogen evolution performance at a universal pH range. The results show that the optimized MoCN-750-2h only needs 86.5, 102.5 and 120.5 mV overpotentials to reach 10 mA·cm−2 in alkaline, acidic and neutral media, respectively. Not only that, MoCN-750-2h had a low Tafel slope (37.2 and 88.5 mV·dec−1) in alkaline and neutral media, implying that catalytic kinetic is close to the level of Pt/C. These results can be attributed to reasonable C and N content in MoCN-750-2 h, optimizing the electron cloud distribution of Mo2C/Mo2N heterostructure to boost hydrogen production. MoCN heterostructure was in-situ synthesized by a two-step method for excellent hydrogen evolution performance at a universal pH range. The optimized electron cloud distribution of Mo2C/Mo2N would promote the formation of electron transfer channels, boosting the hydrogen evolution catalytic activity of the heterostructure. The MoCN heterostructure only needs 86.5,102.5 and 120.5 mV overpotentials to reach 10 mA·cm−2 in alkaline, acidic and neutral media, respectively. Not only that, MoCN-750-2 h had a low Tafel slope (37.2 and 88.5 mV·dec−1) in alkaline and neutral media, implying that catalytic kinetic is close to the level of Pt/C. [ABSTRACT FROM AUTHOR]

In the traditional production of acetic esters, water generated in the esterification reaction can form azeotropes with the ester or the unreacted alcohol, which requires subsequent multi-step distillation or extraction to purify the esters. A large number of intermediate streams in the separation process need to consume a lot of steam to obtain high-purity acetic esters, resulting in a high total energy consumption. In this review, a new extraction separation and purification technology, namely the salting-out effect for the purification of acetic esters, was summarized. Different salting-out agents were used to reduce the concentration of water/alcohols in the ester phase and increase the selectivity coefficient of esters to minimize energy consumption. The scaled particle theory provides a clear guideline for the baseline on the separation goal of the alkyl acetate/alcohol/water systems. Extractive distillation, reactive distillation, azeotropic distillation, pervaporation, adsorption, salting-out assisted distillation, and hybrid salting-out-distillation were compared to assess their advantages and disadvantages. Energy-saving production and separation of acetic esters can be achieved with the hybrid salting-out-distillation process because the salting-out agents are cheap, non-toxic, and non-volatile, and the salting-out process can be conducted at room temperature. [ABSTRACT FROM AUTHOR]

Natural drug research is one of the main directions for the discovery and development of new drugs. Underutilized vegetables with a rich source of medicinal value have drawn much attention from scientists in synthesizing new drugs and finding new pharmacological actions. Apigenin is a natural flavonoid with pharmacological effects including anti-inflammatory, anti-tumor, anti-oxidation, anti-radiation, antidepressant effect, cardiovascular protection, regulated glucose and lipid metabolism, protecting the kidneys, neuroprotection, antibacterial, etc. Thus, these pharmacological effects of apigenin and the interaction between apigenin and drugs were mainly reviewed in this paper. The pharmacological actions of apigenin are being elucidated not only on the molecular level but also on the apigenin-receptor interaction, changes in factors, enzymes, proteins, cells, or tissues. The apigenin derivatives and complexes with their pharmacological actions were also summarized, which is expected to provide a reference for the rational development and utilization of apigenin. [ABSTRACT FROM AUTHOR]