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Catalytic hydrotreatment of humins into cyclic hydrocarbons over solid acid supported metal catalysts in cyclohexane
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作者 Junmin Sun Hai Cheng +5 位作者 Yao Zhang Yinmin Zhang Xunfeng Lan Yongfeng Zhang Qineng Xia Daqian Ding 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第2期329-339,I0011,共12页
Humins are common undesirable sideproducts during many acid-catalyzed reactions in renewable biomass platform conversion. However, few studies have been reported to the efficient utilization of humins.For the first ti... Humins are common undesirable sideproducts during many acid-catalyzed reactions in renewable biomass platform conversion. However, few studies have been reported to the efficient utilization of humins.For the first time, the selective catalytic conversion of biomass-derived humins into cyclic hydrocarbons with high conversion rate and selectivity is presented using a home-made Ru/W-P-Si-O bifunctional catalyst. The multistage polymerization structure of humins was studied through controlled experiments.Results show that the CAC bond network can be efficiently depolymerized at a mild reaction temperature of 340–380 °C, catalyzed by the cooperative catalysis of nano-Ru particles and porous strong Lewis solid acid. Particularly, 95.4% conversion of humins was achieved under the optimal condition with up to 88.3%yield of cyclic hydrocarbons. The detailed composition after liquefaction was also analyzed. This study paves the way for the efficient production of cyclic and aromatic hydrocarbons from furan-derived humin polymer through Lewis acid-catalyzed Diels–Alder reactions between furan rings. 展开更多
关键词 humins HYDROTREATMENT HYDRODEOXYGENATION Bifunctional catalyst Diels–Alder reaction Retro aldol condensation
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Yolk-shell structure synergistic defect engineering for boosting electromagnetic wave absorption in Co_(9)S_(8)@Humins-derived carbon
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作者 Na Liang Zixu Yin +6 位作者 Jingyun Guo Wanying Fang Qi Wang Ge Tian Dong Zhang Huijuan Yue Shouhua Feng 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2023年第33期140-149,共10页
Exploring new strategies to incorporate the concepts of green chemistry and defect engineering into new architectures to address the problem of severe electromagnetic wave(EMW)pollution is challenging.In this work,by ... Exploring new strategies to incorporate the concepts of green chemistry and defect engineering into new architectures to address the problem of severe electromagnetic wave(EMW)pollution is challenging.In this work,by using a by-product of catalytic conversion of biomass as a carbon source,we prepare two-dimensional(2D)Co_(9)S_(8)-coated humins-derived carbon nanomaterials with a yolk-shell structure.The EMW attenuation ability is finally optimized by controlling the morphology and defects of the composite material through the pyrolysis temperature.As expected,with the synergy of conductive loss/interfacial polarization and defects regulating,the composite material achieves a reflection loss(RL)value of−51.4 dB in Ku-band and the effective absorption bandwidth(EAB)can be as high as 5.92 GHz(12.08–18.00 GHz)at 1.8 mm ultra-thin coating thickness.A strong absorption capacity in the low-frequency C-band(6.4 GHz)reaches RL value of−49.9 dB and a thickness of 3.50 mm,which grants it the characteristic of convertible microwave absorption from high frequency to low frequency.Taking account of the facile synthesis and tunable absorption properties,the encouraging findings shed light on exploring waste-turned-microwave absorbents with promising practical applications. 展开更多
关键词 Yolk-shell structure Electromagnetic wave absorption SULFIDE humins
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Mapping out the reaction network of humin formation at the initial stage of fructose dehydration in water
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作者 Xing Fu Yexin Hu +4 位作者 Ping Hu Hui Li Shuguang Xu Liangfang Zhu Changwei Hu 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第6期1016-1026,共11页
The formation of humins hampers the large-scale production of 5-hydroxymethylfurfural(HMF)in biorefinery.Here,a detailed reaction network of humin formation at the initial stage of fructose-to-HMF dehydration in water... The formation of humins hampers the large-scale production of 5-hydroxymethylfurfural(HMF)in biorefinery.Here,a detailed reaction network of humin formation at the initial stage of fructose-to-HMF dehydration in water is delineated by combined experimental,spectroscopic,and theoretical studies.Three bimolecular reaction pathways to build up soluble humins are demonstrated.That is,the intermolecular etherification of β-furanose at room temperature initiates the C12 path,whereas the C-C cleavage of a-furanose at 130-150℃ leads to C11 path,and that of open-chain fructose at 180℃ to C11' path.The successive intramolecular dehydrations and condensations of the as-formed bimolecular intermediates lead to three types of soluble humins.We show that the C12 path could be restrained by using HCl or AlCl_(3) catalyst,and both the C12 and C110 paths could be effectively inhibited by adding THF as a co-solvent or accelerating heating rate via microwave heating. 展开更多
关键词 Carbohydrates 5-HYDROXYMETHYLFURFURAL Reaction network Soluble humins TAUTOMER
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Effects of Fe3+ and Ca2+ on sorption of phenanthrene by Humin in karst soil,Southwest China
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作者 Xianjin An Wei Li +1 位作者 Xinyue Di Jiacheng Lan 《Acta Geochimica》 EI CAS CSCD 2023年第1期125-135,共11页
Humin(HM) is the main organic matter component to af fect the migration and transformation of polycyclic aromatic hydrocarbons(PAHs) in soil. The study on infl uence of the morphology change of inorganic ions on the a... Humin(HM) is the main organic matter component to af fect the migration and transformation of polycyclic aromatic hydrocarbons(PAHs) in soil. The study on infl uence of the morphology change of inorganic ions on the adsorption of PAHs in soil and its organic matter is still rare at microscopic scale. In this paper, yellow soil humin(YS-HM) and lime soil humin(LS-HM) were chosen as samples, then Fe^(3+) and Ca^(2+) were added into samples to facilitate the precipitation by changing the existing conditions of ions, and the mechanism by which inorganic precipitation changed adsorption capacity of karst soil was analyzed from the microscopic scale. The results showed that the adsorption capacity of HM reduced with the inorganic precipitation increasing. The precipitation of Ca^(2+)and Fe^(3+) both reduced the adsorption capacity of YS-HM and LS-HM by 61.71% and 71.83% on average, respectively. The results of scanning electron microscope-energy dispersive spectrometry(SEM-EDS) and pore analysis showed that the HM porosity decreased after formation of Ca^(2+) and Fe^(3+) precipitation. According to the value of Freundlich parameter n, it may be because the precipitation or colloid of Ca^(2+) and Fe^(3+) fi lled micropores and covers high-energy adsorption sites of the HM. This research provides theoretical support for studying the PAHs migration and bioavailability of Calcium-rich in karst soil. 展开更多
关键词 Inorganic ions HUMIN PHENANTHRENE Adsorption SOIL KARST
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Extraction and Characterization of Humic Acids and Humin Fractions from a Black Soil of China 被引量:47
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作者 XINGBao-Shan LIUJu-Dong +1 位作者 LIUXiao-Bing HANXiao-Zeng 《Pedosphere》 SCIE CAS CSCD 2005年第1期1-8,共8页
Twenty-three progressive extractions were performed to study individual humic acids (HAs) and humin fractions from a typical black soil (Mollisol) in Heilongjiang Province, China using elemental analysis and spectrosc... Twenty-three progressive extractions were performed to study individual humic acids (HAs) and humin fractions from a typical black soil (Mollisol) in Heilongjiang Province, China using elemental analysis and spectroscopic techniques. After 23 HA extractions the residue was separated into high and low organic carbon humin fractions. HA yield was the highest for the first extraction and then gradually decreased with further extractions. Organic carbon (OC) of the humin fractions accounted for 58% of total OC … 展开更多
关键词 elemental composition humic acid HUMIN soil organic matter spectroscopic analysis
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Carbon Sequestration in Soil Humic Substances Under Long-Term Fertilization in a Wheat-Maize System from North China 被引量:12
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作者 SONG Xiang-yun LIU Shu-tang +2 位作者 LIU Qing-hua ZHANG Wen-ju HU Chun-guang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第3期562-569,共8页
The changes in humic substances (HS) is fundamental in detecting soil carbon sequestration mechanisms in natural and cultivated environments. Based on a long-term trial, the amounts of water dissolved substances (... The changes in humic substances (HS) is fundamental in detecting soil carbon sequestration mechanisms in natural and cultivated environments. Based on a long-term trial, the amounts of water dissolved substances (WSS), humic acid (HA), fulvic acid (FA) and humin (HU) were determined to explore the impact of long-term fertilization on HS. Increases in the amounts of WSS, HA, FA and HU were significant different among the treatments with manure. A significant correlation was found between the increased soil organic carbon (SOC) and HS (R^2=0.98, P〈0.01). The change in the E4/E6 ratio was significantly correlated with the increased SOC (R2=0.88, P〈0.01), HA (R^2=0.91, P〈0.01), FA (R^2=0.91, P〈0.01) and HU (R^2=0.88, P〈0.01). The cluster was mainly divided into two parts as manure fertilization and inorganic fertilization, based on the increases in HA, FA and HU. These results suggest that long term fertilization with manure favours carbon sequestration in HS and is mainly stabilized as HU, while the HA becomes more aliphatic. We conclude that increases in SOC can be linked to changes in the molecular characteristics of HS fractions under long term fertilization. 展开更多
关键词 carbon sequestration humic acid HUMIN long term fertilization E4/E6 ratio
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Characteristics of humin fractions associated with inorganic minerals obtained by NaOH,and NaOH assisted with anthraquinone extraction procedures 被引量:1
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作者 韩桂洪 姜涛 +2 位作者 黄艳芳 张元波 李光辉 《Journal of Central South University》 SCIE EI CAS 2012年第8期2286-2290,共5页
The differences in XRD patterns, elemental compositions, FT-IR spectra and TG-DSC curves of extract residues obtained by NaOH, and NaOH assisted with anthraguinone (AQ) extraction procedures were studied. The extrac... The differences in XRD patterns, elemental compositions, FT-IR spectra and TG-DSC curves of extract residues obtained by NaOH, and NaOH assisted with anthraguinone (AQ) extraction procedures were studied. The extract residues are mainly comprised of humin fractions associated with inorganic minerals. XRD analysis shows that there is no typical peak of organic carbon because those organic humin fractions appear as a highly disordered substance. The peak of quartz is dominant. The elementary analysis shows that assistant AQ in NaOH solution can break the link of organic humic substances with inorganic minerals. And aromatization degree of humin fractions obtained by NaOH is smaller than that obtained by NaOH assisted with AQ. FT-IR analysis displays that various groups exist in those two humin fractions obtained by different extraction procedures. There are some differences in FT-IR curves between two humin fractions. TG-DSC analysis shows that thermal decomposition occurs during the heating of testing samples. By contrast, the humin fractions associated with inorganic minerals obtained by NaOH possess a higher thermal decomposition range. 展开更多
关键词 organic binder humin fraction infrared spectrum oxidized pellets
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Adsorption mechanism of Cd(Ⅱ)by calcium‑modifed lignite‑derived humin in aqueous solutions
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作者 Ping Wang Zhanbin Huang +4 位作者 Zhanyong Fu Peng Zhao Zeshen Feng Yao Wang Fangze Li 《International Journal of Coal Science & Technology》 EI CAS CSCD 2022年第3期221-231,共11页
Lignite-derived humin(CHM)was extracted from raw coal in Heihe City,China,producing calcium-modifed lignite-derived humin(Ca-CHM)by Ca(OH)_(2).The physical and chemical performances of CHM and Ca-CHM were analyzed wit... Lignite-derived humin(CHM)was extracted from raw coal in Heihe City,China,producing calcium-modifed lignite-derived humin(Ca-CHM)by Ca(OH)_(2).The physical and chemical performances of CHM and Ca-CHM were analyzed with SEM,^(13)C spectra and XPS techniques.The results show that Ca-CHM exhibited weaker aliphatic,more aromatic polar compared with CHM,which improves the adsorption capacity for Cd(Ⅱ).XPS analysis indicates that Ca(Ⅱ)has been loaded onto Ca-CHM successfully after modifcation.This batch adsorption experiments report the adsorption performance of CHM and Ca-CHM for Cd(Ⅱ).The adsorption process of CHM and Ca-CHM for Cd(Ⅱ)conform to pseudo-second-order model,which is chemical adsorption,and the adsorption data presented good fts to the Langmuir model.The maximum adsorption amount(Q_(m))of Cd(Ⅱ)onto CHM and Ca-CHM by the Langmuir model is 15.29 mg/g and 41.84 mg/g,respectively.Based on the results of SEM,^(13)C spectra,and XPS analysis,we concluded that the main adsorption mechanism of Ca-CHM on Cd(Ⅱ)was ion exchange of Cd(Ⅱ)for Ca(Ⅱ),static-adsorbed and surface complexation.Therefore,Ca(Ⅱ)can be loaded on the surface of Ca-CHM by chemical modifcation,improving the adsorption capacity of materials in aqueous solutions. 展开更多
关键词 Lignite-derived humin Modifcation CD(II) Adsorption Mechanism
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Humic substances:Structure,function and benefits for agroecosystems—a review 被引量:2
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作者 Jaya TIWARI AL RAMANATHAN +1 位作者 Kuldeep BAUDDH John KORSTAD 《Pedosphere》 SCIE CAS CSCD 2023年第2期237-249,共13页
The increasing global demand for food production,often causing excessive use of chemical fertilizers,has led to the deterioration of soil health.Immediate action is required to restore soil health in a sustainable man... The increasing global demand for food production,often causing excessive use of chemical fertilizers,has led to the deterioration of soil health.Immediate action is required to restore soil health in a sustainable manner.This review advocates switching to use of organic matter(manure and compost)that contains vital nutrients for plant growth and helps restore soil health.Humic substances(HSs),derived from degraded plant remains and found ubiquitously in nature,are an important source of organic matter.The application of HSs to soil enhances essential nutrient supply and assimilation of atmospheric CO_(2)due to increasing biomass yield.Promoting HS application globally can help lower atmospheric CO_(2)concentrations and create a sustainable agricultural practice.However,the process of humification and the molecular structure of HSs remain poorly understood subjects in soil science.Therefore,it is imperative to understand the mechanisms underlying various roles of HSs in agroecosystems.This review offers an insight into the various structural and functional aspects of HSs,particularly fulvic acid and humic acid.The dynamic and interactive nature of HSs creates a framework for sustainable agriculture. 展开更多
关键词 fulvic acid humic acid HUMIN HUMUS nutrient supply soil health sustainable agriculture
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Latitudinal patterns and influencing factors of soil humic carbon fractions from tropical to temperate forests 被引量:7
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作者 徐丽 王春燕 +5 位作者 朱剑兴 高扬 李美玲 吕瑜良 于贵瑞 何念鹏 《Journal of Geographical Sciences》 SCIE CSCD 2018年第1期15-30,共16页
Soil humic carbon is an important component of soil organic carbon (SOC) in ter- restrial ecosystems. However, no study to date has investigated its geographical patterns and the main factors that influence it at a ... Soil humic carbon is an important component of soil organic carbon (SOC) in ter- restrial ecosystems. However, no study to date has investigated its geographical patterns and the main factors that influence it at a large scale, despite the fact that it is critical for exploring the influence of climate change on soil C storage and turnover. We measured levels of SOC, humic acid carbon (HAC), fulvic acid carbon (FAC), humin carbon (HUC), and extractable humus carbon (HEC) in the 0-10 cm soil layer in nine typical forests along the 3800-km North-South Transect of Eastern China (NSTEC) to elucidate the latitudinal patterns of soil humic carbon fractions and their main influencing factors. SOC, HAC, FAC, HUC, and HEC increased with increasing latitude (all P〈0.001), and exhibited a general trend of tropical 〈 subtropical 〈 temperate. The ratios of humic C fractions to SOC were 9.48%-12.27% (HAC), 20.68%-29.31% (FAC), and 59.37%-61.38% (HUC). Climate, soil texture, and soil microbes jointly explained more than 90% of the latitudinal variation in SOC, HAC, FAC, HEC, and HUC and interactive effects were important. These findings elucidate latitudinal patterns of soil humic C fractions in forests at a large scale, and may improve models of soil C turnover and storage. 展开更多
关键词 humic acid carbon HUMIN LATITUDE pattern soil organic carbon NSTEC
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Experimental and molecular dynamic simulation study of perfluorooctane sulfonate adsorption on soil and sediment components 被引量:7
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作者 Ruiming Zhang Wei Yan Chuanyong Jing 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2015年第3期131-138,共8页
Soil and sediment play a crucial role in the fate and transport of perfiuorooctane sulfonate (PFOS) in the environment. However, the molecular mechanisms of major soil/sediment components on PFOS adsorption remain u... Soil and sediment play a crucial role in the fate and transport of perfiuorooctane sulfonate (PFOS) in the environment. However, the molecular mechanisms of major soil/sediment components on PFOS adsorption remain unclear. This study experimentally isolated three major components in soil/sediment: humin/kerogen, humic/fulvic acid (HA/FA), and inorganic component after removing organics, and explored their contributions to PFOS adsorption using batch adsorption experiments and molecular dynamic simulations. The results suggest that the humin/kerogen component dominated the PFOS adsorption due to its aliphatic features where hydrophobic effect and phase transfer are the primary adsorption mechanism. Compared with the humin/kerogen, the HA/FA component contributed less to the PFOS adsorption because of its hydrophilic and polar characteristics. The electrostatic repulsion between the polar groups of HA/FA and PFOS anions was attributable to the reduced PFOS adsorption. When the soil organic matter was extracted, the inorganic component also plays a non-negligible role because PFOS molecules might form surface complexes on SiO2 surface. The findings obtained in this study illustrate the contribution of organic matters in soils and sediments to PFOS adsorption and provided new perspective to understanding the adsorption process of PFOS on micro-interface in the environment. 展开更多
关键词 Humic/fulvic acid Humin/kerogen PFOS Adsorption Molecular dynamics
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Solid-State 13C Nuclear Magnetic Resonance Spectroscopic Characterization of Soil Organic Matter Fractions in a Forest Ecosystem Subjected to Prescribed Burning and Thinning 被引量:1
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作者 thilini d.ranatunga zhongqi he +1 位作者 kamala n.bhat junyan zhong 《Pedosphere》 SCIE CAS CSCD 2017年第5期901-911,共11页
Forest management practices such as prescribed burning and thinning in forest ecosystems may alter the properties of soil organic matter (SOM). In this study, surface softs from field plots in the Bankhead National ... Forest management practices such as prescribed burning and thinning in forest ecosystems may alter the properties of soil organic matter (SOM). In this study, surface softs from field plots in the Bankhead National Forest, Alabama, USA, were used to investigate possible SOM transformations induced by thinning and burning. Elemental analysis and solid-state 13C cross polarization magic angle spinning nuclear magnetic resonance (13C CPMAS NMR) spectroscopy were used to characterize SOM fractions in whole soils, humic substances, and density fractions. Our data revealed that the changes in SOM fractions due to the repeated burning carried out in the forest ecosystem studied were involved mainly with alkyl C, O-alkyl C, and carbohydrate functional groups, implying that most prominent reactions that occurred involved dehydrogenation, de-oxygenation, and decarboxylation. In addition, burning and thinning might have also affected the distribution and composition of free and occluded particulate SOM fractions. The limited structural changes in SOM fractions suggested that low-intensity prescribed fire in the forest ecosystem studied will not create major structural changes in SOM fractions. 展开更多
关键词 density fractionation forest fires forest management practices forest soils fulvic acids humic acids HUMIN particulateorganic matter
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Reliability of radiocarbon dating on various fractions of loess-soil sequence for Dadiwan section in the western Chinese Loess Plateau
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作者 Zongli WANG Hui ZHAO +3 位作者 Guanghui DONG Aifeng ZHOU Jianbao LIU Dongju ZHANG 《Frontiers of Earth Science》 SCIE CAS CSCD 2014年第4期540-546,共7页
The accurate radiocarbon dating of loess-soil sequences plays an essential role in the reconstruction of the environmental and climatic changes in continental settings during the last glaciation and Holocene. However,... The accurate radiocarbon dating of loess-soil sequences plays an essential role in the reconstruction of the environmental and climatic changes in continental settings during the last glaciation and Holocene. However, our knowledge about the reliability of radiocarbon ages of various fractions of soil and loess samples is still insufficient. Here, we present our study results on radio- carbon ages based on bulk organic matter, humin fraction, and carbonate of samples collected from a loess-paleosol section in the western Chinese Loess Plateau. We compare these observations with the optically stimulated luminescence ages and charcoal radiocarbon ages to evaluate the reliability of these fractions. We observed that the radio- carbon ages of humin fraction are very close to those of charcoal and are consistent with the optically stimulated luminescence ages within the experimental errors. We observed a significant deviation in the radiocarbon ages of carbonate and bulk organic matter from those of charcoal and optically stimulated luminescence ages, likely due to the dilution of these fractions during the pedogenetic process. Our results reveal that, except for charcoal, the humin fraction may yield reliable laC ages for the Chinese loess-soil sequence. 展开更多
关键词 loess-soil sequence humin fraction charcoal organic matter radiocarbon dating
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