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In this work, poly ethylene oxide (PEO) with various molecular weights (MW)s was employed to separate the lignin of prehydrolysis liquor (PHL) of a kraft-based dissolving pulp process. The results revealed that, the higher the MW and concentration of PEO in the PHL at pH 2, the higher are the removals of lignin and chemical oxygen demand (COD) but with a marginal removal of sugars. Alternatively, poly aluminum chloride (PAC) (200 mg/L) and PEO (8 MDa MW) (200 mg/L) were employed in a dual polymer system to extract the lignin, and the PAC/PEO system (MWs of 2 kDa/8 MDa) was more effective than the PEO/PEO system (MWs of 0.1 MDa/8 MDa) in removing lignin and COD of PHL. The maximum lignin, sugar, and COD removals were 46%, 18.8%, and 32%, respectively, under the conditions of 400 mg/g PEO (with a MW of 8 MDa) at pH 2 and room temperature in a singular PEO system.

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For the first time, waste-seashell-derived CaO catalysts were used as high-performance solid base catalysts for cyclopentanone self-condensation, which is an important reaction in bio-jet fuel or perfume precursor synthesis. Among the investigated seashell-derived catalysts, Scapharca Broughtonii-derived CaO catalyst (S-shell-750) exhibited the highest dimer yield (92.1%), which was comparable with commercial CaO (88.2%). The activity sequence of different catalysts was consistent with the CaO purity sequence and contact angle sequence. X-ray diffraction (XRD) results showed that CaCO3 in waste shell were completely converted to CaO after calcination at 750 °C or above for 4 h. CO2 temperature-programmed desorption (CO2-TPD) results indicate that both the amount and strength of base sites increase significantly when the calcination temperature climbs to 750 °C. Therefore, we can attribute the excellent performance of S-shell-750/850/950 catalysts to the higher CaO content, relatively low hydrophilicity, and stronger acidity and basicity of this catalyst. This study developed a new route for waste shell utilization in bio-derived ketone aldol condensation.

A strategy of preparing afterglow materials has been achieved by immobilizing carboxymethylated lignin-based carbon dots into silica, which provides a new path for the high-value utilization of lignin.

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For the first time, ball-milling was introduced as an efficient process for the condensation of biomass-derived cyclopentanone using commercial CaO as a catalyst. Compared with traditional magnetic stirring methods ("heat input" methods), ball-milling is an alternative "energy input" method. CaO dosage, rotation speed, and reaction time were investigated for optimal condition screening, and the ball-milling method could achieve a high yield (98.9%) and a high selectivity (99.2%) under lower energy demand conditions at mild temperature (∼40 °C). Moreover, the power hypothetically needed for dimer per mole (E 2 ) of the ball-milling method was comparable or even lower than that for the magnetic stirring method after our assessment. In addition, we also explored the applicability of the ball-milling method for the condensation of other biomass-derived aldehydes and ketones. Competitive yield was obtained using heterogeneous CaO as a catalyst. Due to the intense stirring in ball-milling, the CaO catalyst was mixed uniformly with reactants, and higher surface area was also obtained due to the decrease of the particle size during the ball-milling method, which may also benefit the reaction and increase the catalytic activity. This way would tally with the concept of green chemistry and economic efficiency, which has the potential for industrial applications.