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Your search keyword '"Guo, Xingjie"' showing total 507 results
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21. Composite fiber as a multifunctional catalyst support for the upgradation of lignin-based chemicals

Author

Li, Zuzhi, Ma, Ya, Guo, Xingjie, Cao, Yang, Jiang, Qian, Gao, Mi, Liu, Xudong, Tsang, Daniel C. W., Jiang, Zhicheng, Shi, Bi, Li, Zuzhi, Ma, Ya, Guo, Xingjie, Cao, Yang, Jiang, Qian, Gao, Mi, Liu, Xudong, Tsang, Daniel C. W., Jiang, Zhicheng, and Shi, Bi

Abstract

Efficient catalytic hydrogenation of lignin-based derivative vanillin (VAN) into valuable chemicals with a high selectivity is important yet challenging because of the lack of selective and active catalysts. Herein, a mixture of polyacrylonitrile (PAN) and water-insoluble tannin (Tan) was employed to create composite fibers through the electrospinning process, resulting in PAN-Tan composite fibers. The formation of hydrogen bonds between the -CN group of PAN and the phenolic -OH group of Tan proved advantageous for high dispersion and reduced physical entanglement, resulting in the production of thinner fibers. Leveraging abundant ortho-phenolic -OH groups of Tan, the PAN-Tan fibers were used to adsorb Pd2+ ions, which were reduced by in situ reduction process to Pd0 particles. Higher solute concentrations in the spinning solution improved the homogeneity of the electrospun PAN-Tan fibers, facilitating the dispersion and reduction of adsorbed Pd2+ on the fiber surface. Subsequently, these Pd/PAN-Tan fibers served as catalysts for the selective hydrogenation of the -CHO group of VAN to produce vanillyl alcohol (VAL) in an aqueous phase. Over 99% of VAN could be hydrogenated into VAL at 50 degrees C for 60 min under 0.5 MPa H2. Moreover, the catalyst exhibited universal applicability for the hydrogenation of diverse typical lignin-based aromatic aldehydes. The catalytic hydrogenation of VAN was then extended to a fixed-bed reactor for 24 h, and only VAL was detected in the effluent. Our study underscored the low energy consumption for catalyst preparation without additional reducing agents and high temperature carbonization process, the stability and reusability of the Pd/PAN-Tan fiber catalyst and its potential for large-scale industrial applications. PAN-Tan fiber could in situ anchor and reduce Pd2+ ions for the subsequent catalysis of vanillin hydrogenation.

Published
2024

42. Evaluation of Biochar and Inorganic Fertilizer on Soil Available Phosphorus and Bacterial Community Dynamics in Acidic Paddy Soils for Different Incubation Temperatures.

Author

Sarfraz, Rubab, Nadeem, Faisal, Yang, Wenhao, Tayyab, Muhammad, Khan, Muhammad Israr, Mahmood, Rashid, Guo, Xingjie, Xing, Shihe, and Kim, Gil Won

Subjects
ACID soils, BACTERIAL communities, BIOCHAR, SOIL amendments, RED soils
Abstract

The composition of microbial communities and the functioning of ecosystems are greatly influenced by the nutrient inputs. Despite this fact, our knowledge regarding the impact of phosphorus (P) inputs on soil P availability and microbial community structures in subtropical acidic soils remains limited. We hypothesized that diverse P inputs, incubation temperatures, and soil types could significantly alter soil P availability and microbial communities. To address this gap, we conducted a laboratory incubation experiment, investigating the effects of biochar and inorganic P amendments on soil available P, soil pH, acid phosphatase enzymes, and bacterial abundance. We employed two different incubation temperatures (15 °C and 25 °C) using acidic paddy soil and red soil from the subtropical Southern China region. Our results indicate a notable increase in soil pH, reaching 37% and 39% at 15 °C and 40% and 40.6% at 25 °C, respectively, following the application of biochar and inorganic P amendments in paddy soil. In the case of red soil, we observed pH increases of 41% and 43% at 15 °C and 44% and 45% at 25 °C after the application of biochar and inorganic P amendment, respectively. The addition of inorganic P amendment resulted in the highest available P contents in paddy soil, reaching 111.47 mg/kg at 15 °C and 100.17 mg/kg at 25 °C, respectively. However, Proteobacteria decreased after inorganic P addition, which showed that P might not be the only limiting nutrient for various bacterial communities. Bacterial diversity and richness indices were found to be higher after biochar application in both soils. Gemmatimonadetes, Acidobacteria, and Actinobacteria were found to be strongly influenced by incubation temperatures, whereas most of the top abundant bacterial phyla, such as Gemmatimonadetes, Actinobacteria, Chloroflexi, Acidobacteria, Planctomycetes, Firmicutes, Patescibacteria, and Bacteroidetes, were highly dependent on soil type. At the genus level, various important P solubilizing genera (Pseudomonas, Bradyrhizobium, Streptomyces jietaisiensis, Massilia) significantly increased after biochar and inorganic P addition in both soils. The correlation analysis proved that P-solubilizing genera were significantly associated with changes in soil pH, as well as soil available P after biochar and inorganic P addition. Conclusively, in a short-term incubation experiment, inorganic P amendment greatly increased the soil pH and available phosphorus contents compared to biochar and control treatments; however, the microbial community was observed to be strongly associated with biochar application, soil type, and incubation temperature. [ABSTRACT FROM AUTHOR]

Published
2024
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