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Hemicellulose is a carbohydrate biopolymer second only to cellulose, which is rich and has a broad application prospect. The limitation of high-value utilization of hemicellulose has been a long-standing challenge due to its complex and diversified structure. The extraction and subsequent modification of hemicellulose from lignocellulosic biomass represent a promising pathway toward this goal. Herein, the extraction processes including physical pretreatment, chemical pretreatment, and combined pretreatment for separating hemicellulose from lignocellulosic biomass were introduced, and the advantages and disadvantages of various extraction procedures were also described. The chemical modification of hemicellulose such as etherification, esterification, grafting, and cross-linking modification was reviewed in detail. The separation and modification of hemicellulose in the future are prospected based on the earlier studies.

In this paper, the effects of nano-zero valent iron (nZVI) on anaerobic digestion of sulphate wastewater with different SO 4 2 − /COD ratios, including the COD removal rate, methane yield, intermediate products and the change of microbial community structure, were investigated. The results showed that nZVI could effectively enhance the treatment efficiency and methane yield. Compared with the control group without nZVI, the methane yield increased from 348.6833 to 1007.05 mL CH4/gCODremoval with 4 g nZVI loading at SO 4 2 − /COD = 0.1. nZVI could make electron flow from sulphate reduction to methane production, which increased methane yield even at high sulphate concentration. The microbial community analysis showed that adding nZVI could increase the abundance of acetoclastic methanogens, which accelerated hydrolysis acidification. [ABSTRACT FROM AUTHOR]

Co-pyrolysis characteristics of rice husk and cow manure using SnCl2, ZnCl2 and Fe3O4 as an additive were studied in a fixed tubular furnace. The effects of additive loading amount (0–20 wt.%) on the pyrolysis processes were investigated. The thermogravimetric-derivative thermogravimetric results showed that the weight loss rate was increased with the increase of additive content. There was no obvious shoulder peak appeared after the addition of Fe3O4, while the peak of weight loss was moved to the low-temperature region with the ZnCl2 addition. Gas yield was increased with the increase of Fe3O4 content while it was decreased after the addition of SnCl2 and ZnCl2. The highest gas yield (0.39 Nm3/kg) was obtained at 20% Fe3O4. At the same time, the additives could obviously improve the quality of syngas which promoted H2 content and reduced CO content. The H2 content was increased by 7.9%, 8.88%, and 4.44%, respectively, for SnCl2, ZnCl2, and Fe3O4. The results of GC/MS showed that the additives promoted hydrogen bond breaking and the cracking of macromolecules resulting in an increase of small polycyclic aromatic hydrocarbons production. Meanwhile, the additives made a great influence on the oxygen-containing functional groups in the biochar, which increased the content of O–H and O–C–O functional groups. [ABSTRACT FROM AUTHOR]

In this paper, the influences of biochar on the anaerobic digestion of sulphate wastewater, including the COD removal rate, methane yield, intermediate products and the change of microbial community structure, were investigated. The results showed that sulphate could promote the anaerobic digestion with the SO42−/COD ratio increasing from 0 to 0.1, while the activity of MPB was inhibited, which led to the decrease of COD removal rate and methane yield with the SO42−/COD ratio increasing from 0.1 to 2. At 1 g biochar loading, 344.97 mL CH4/gCODremoval was obtained compared with the control group (220.70 CH4/gCODremoval) at 2 of SO42−/COD. Biochar could also reduce the secondary accumulation of NH4+–N and TVFA. Meanwhile, methanogenic microorganisms were selectively enriched especially for methanobacterium, methanosaeta and methanolinea, while the growth of SRB was inhibited with biochar addition. [ABSTRACT FROM AUTHOR]

Concerning the increasing greenhouse effect, the development of efficient CO2 adsorbents is very important. In this study, the influence of surfactant on the adsorption performance of amine-functionalized MCM-41 was analysed. The results showed that the residual amount of surfactant in MCM-41 was gradually decreased with the increase of calcination temperature which improved the pore structure. The maximum adsorption capacity (5.495 mmol/g) appeared at PEI-MCM-41-100°C indicated that the adsorption capacity could be improved under the function of surfactant. By calculating the diffusion coefficient of CO2 adsorption process in PEI-MCM-41-100/200/300/400/550°C, the diffusion resistance of CO2 was the lowest in PEI-MCM-41-100°C, which directly proved that the synergism of surfactant and organic amine could reduce the diffusion resistance of CO2 in the pore. [ABSTRACT FROM AUTHOR]

In this paper, rice husk (RH) was used as raw material to prepare white carbon black, and the key technological parameters of preparing white carbon black from RH were studied through single‐factor test, orthogonal experiment, and response surface analysis. Meanwhile, the characteristic of white carbon black was also analyzed. Through orthogonal experiment analysis, it was confirmed that the order of factors affecting the purity of white carbon black was calcination temperature > alkali treatment time > final pH > surfactant. Based on the response surface optimization analysis, the optimum parameters for preparation of white carbon black were as follows: calcination temperature 610°C, alkali treatment time of 2.3 hr, final pH of 10, CTMAB was used as the surfactant. Under this condition, the purity of silica prepared could be reached to 99.39%, and the particle size was uniform, spherical, and well dispersed, which satisfied the requirements of GB/T 34698‐2017 standard. [ABSTRACT FROM AUTHOR]