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A heterojunction structure LaVO4/g-C3N4 composite with oxygen defects was successfully prepared. The characterization results show that the recombination of electron–hole pairs could be inhibited by the heterojunction structure. The LaVO4/g-C3N4 composite shows superior photocatalytic water splitting performance for the generation of hydrogen and oxygen under visible light irradiation. Experimental data show that under visible light irradiation, the hydrogen and oxygen evolution rates of the LVOCN1 composite are much higher than those of fresh carbon nitride. Moreover, the photocatalytic activity of LaVO4/g-C3N4 composites could be significantly enhanced by O defects. Mechanism studies display that the possible mechanism of the photocatalytic water splitting reaction is the Z scheme mechanism. [ABSTRACT FROM AUTHOR]

Abstract: Growing concern about sulfur dioxide (SO2) emission from diesel exhaust causing a serious threat to the environment and human health necessitated enhanced desulfurization materials for dry desulfurization filters. MnO2 was modified with various alkali metal ions by impregnation to strengthen its SO2 capture capacity. The prepared materials were characterized by various technologies. Their SO2 capture capacities were measured by thermogravimetry, and the sulfate reaction mechanism was also evaluated. The results confirm that the SO2 capture performance of MnO2 could be significantly enhanced by doping with alkali metals. The prepared Li‐doped MnO2 has good SO2 trap capacity with improved absorbance being 64 % higher than that of MnO2. The grain model can be applied to explain the sulfate reaction mechanism between Li‐doped MnO2 and SO2. The activation energy was calculated by the grain model equations. [ABSTRACT FROM AUTHOR]

Extraction of high-value products from agricultural wastes is an important component for sustainable bioeconomy development. In this study, wax extraction from sugarcane bagasse was performed and the beneficial effect of dewaxing pretreatment on the enzymatic hydrolysis was investigated. About 1.2% (w/w) of crude sugarcane wax was obtained from the sugarcane bagasse using the mixture of petroleum ether and ethanol (mass ratio of 1:1) as the extraction agent. Results of Fourier-transform infrared characterization and gas chromatography–mass spectrometry qualitative analysis showed that the crude sugarcane wax consisted of fatty fractions (fatty acids, fatty aldehydes, hydrocarbons, and esters) and small amount of lignin derivatives. In addition, the effect of dewaxing pretreatment on the enzymatic hydrolysis of sugarcane bagasse was also investigated. The digestibilities of cellulose and xylan in dewaxed sugarcane bagasse were 18.7 and 10.3%, respectively, compared with those of 13.1 and 8.9% obtained from native sugarcane bagasse. The dewaxed sugarcane bagasse became more accessible to enzyme due to the disruption of the outermost layer of the waxy materials. [ABSTRACT FROM PUBLISHER]

In this study, fly ash and hydrogen peroxide (H 2 O 2 ) assisted hydrothermal carbonization (HTC) was used to improve the removal efficiency of nitrogen (N) and sulfur (S) from sewage sludge (SS). The removal rate and distribution of N and S in hydrochar were evaluated, and properties of the aqueous phase were analyzed to illustrate the N and S transformation mechanism during fly ash and H 2 O 2 assisted HTC treatment of SS. The results suggested that during HTC process assisted by fly ash (10% of raw SS), dehydration, decarboxylation and hydrolysis of SS were strengthened due to the catalysis effect. The N and S removal were promoted marginally. For hydrochar achieved from HTC process with H 2 O 2 addition, the N and S removal were improved slightly due to the biopolymer oxidization by ‧OH released from H 2 O 2 decomposition. While for HTC treatment with fly ash and H 2 O 2 supplementation, a positive synergistic effect on N and S removal was observed. The N and S removal obtained from fly ash (10% of raw SS) and H 2 O 2 (48 g/L) assisted HTC increased to 81.71% and 62.83%, respectively, from those of 69.53% and 49.92% in control group. N and S removal mechanism analysis suggested that hydroxyl radicals (‧OH) produced by H 2 O 2 decomposition will destroy SS structure, and the biopolymers such as polysaccharides and proteins will be decomposed to release N and S into the liquid residue. In addition, the fly ash acts as the catalyst will decrease the energy need for denification and desulfartion. Consequently, N and S removal efficiency was enhanced by fly ash and H 2 O 2 assisted HTC treatment., (Copyright © 2021 Elsevier Ltd. All rights reserved.)