Journal of Energy Storage
·
2025
·
IF 9.8
Meiyu Zhou,Lin Wang,Yunpeng Li,Xiaoqing Liu,Jun Liu,Yongfa Zhang,Yongliang Ma,Junhua Li,Jingcheng Hao,Xu Wu
Lignite, a low-rank coal with abundant reserves, plays a crucial role in enhancing energy efficiency and mitigating environmental pollution through quality enhancement and improved utilization. Its large supply, low cost, well-developed pore structure, and functional groups make it a valuable starting material for fabricating porous carbon materials used in supercapacitors. During the preparation, a special chemical treatment can create the appropriate pore structure and a large surface area, which helps to speed up ion transport and enhances the supercapacitor performance. This study presents an innovative method for producing coal-based activated carbon (PAC) using an optimized supercritical methanol/alkali treatment. The resulting PAC exhibited a high surface area of 1616.9 m 2 g −1 , a significant microporous volume of 0.78 cm 3 g −1 , and an appropriate percentage of micropores (85.71 %). The PAC electrode achieved a specific capacitance of 263.2 F g −1 at 1 A g −1 , while a PAC//PAC symmetric supercapacitor exhibited an exceptional performance, with an energy density of 16.48 Wh kg −1 at 500 W kg −1 and 1 A g −1 , along with a 98 % capacity retention after 20,000 cycles at 5 A g −1 . This method enables the precise removal of certain oxygen-containing groups from lignite, making it a more environmentally friendly and cost-effective option than traditional chemical activation, while also using less acid and creating a higher number of defective sites. The resulting porous carbon material features a larger specific surface area, a lower ash content, and superior properties.
研究领域:
材料科学
·
能源化学
·
电化学
·
环境功能材料
·
碳材料
✓ 已验证
产品关联
DOI
高影响因子
ENERGY & FUELS
·
2017
·
IF 3.091
Fan Yang,Yucui Hou,Muge Niu,Ting Lu,Weize Wu,Zhenyu Liu
Carboxylic acids (CAs) are considered as an important group of chemicals and are widely used in the chemical industry. The production of CAs via oxidation of lignite is a promising industrial process. In the present work, we found that H5PV2Mo10O40 (HPA) was beneficial to catalytic oxidation of lignite by O2 in aqueous H2SO4 solutions to produce CAs. The effects of HPA concentration, H2SO4 concentration, reaction temperature, initial O2 pressure, and reaction time on lignite conversion and CA yield were studied. The catalytic oxidation of lignite in aqueous HPA/H2SO4 solutions with O2 can yield 56.9 wt % CAs, including 33.5 wt % formic acid, 14.4 wt % acetic acid, 1.5 wt % succinic acid, 1.1 wt % oxalic acid, and 6.4 wt % benzene carboxylic acids (BCAs, including 12 types) at 170 °C and 3 MPa for 60 min. In this catalyst system, the existence of H2SO4 can change the catalytic activity of HPA, and the synergistic effect of HPA and H2SO4 can significantly promote the production of CAs. VV can oxidize lignite or intermediates to form VIV, which can be reoxidized by O2 to complete a redox cycle. In the catalytic oxidation, lignite was converted into water-soluble intermediates at first, and then the water-soluble intermediates were converted to CAs. The catalyst system was reused four times without significant decline in activity. Compared with the traditional alkali-oxygen oxidation, this method can decrease the usage of mineral acid and alkali and lower reaction temperatures.
研究领域:
能源化学
·
工业催化
·
环境化学
·
有机化学
·
资源利用
✓ 已验证
DOI
高影响因子
MINERALS ENGINEERING
·
2020
·
IF 3.795
Hongliang Li,Rui Li,Mengmeng Wang,Jianbo Li,Yafeng Fu,Benkang Zhu
Previous studies verified that the moisture adsorption on the lignite can be reduced by adsorption of surfactant on the surface. However, these surfactant adsorption processes were realized in aqueous solutions, result in a great deal of water bring into the system. It seems that the surfactant is affinity to the surface of lignite and the adsorption can be realized in dry condition with a well-designed method. In this study, we propose a method to reduce the adsorption of moisture by lignite in dry condition, by mechanically mixing it with a surfactant in a ball mill. The surfactant is adsorbed by the lignite surface toward due to the electrostatic interactions during the mixing process, which makes the lignite surface hydrophobic. Untreated and treated samples of lignite were exposed in an environment of 100% relative humidity, maintained at 20 °C, for 36 h. Compared to the untreated sample, the moisture content in the treated sample decreased from 25.9% to 11.6%. This reduction in the adsorbed moisture content is due to the modification of the hydrophobicity of the original sample. The particle size of the lignite decreases significantly after ball milling. As the particle size required for the commercial utilisation of lignite is usually low, the proposed method can be applied after the dry beneficiation process.
研究领域:
环境科学
·
材料科学
·
化学工程
·
能源技术
✓ 已验证
DOI
高影响因子
Journal of Energy Storage
·
2026
·
IF 10.7
Guangchao Hu,Haokun Li,Fangqin Cheng,Xiangtao Huo,Min Guo,Mei Zhang
A low-cost, porous carbon aerogel derived from lignite has been successfully developed as an electrode material for supercapacitors designed for high-efficiency energy storage. The assembled device achieves an energy density of 7.92 Wh kg −1 , making it highly competitive. Unlike traditional methods requiring extensive cleaning, this work employs a mild, acid-free H 2 O 2 oxidation strategy to directly convert lignite into soluble precursors without extra impurity removal steps. This green approach significantly simplifies the preparation process and reduces chemical consumption. The selective oxidation introduces abundant oxygen-containing groups (e.g., -COOH, -OH), which facilitate the formation of a robust sol-gel network and induce a hierarchical microporous–mesoporous architecture (average pore size: 3.76 nm) during carbonization. Consequently, the optimized material (CA-700) delivers a specific capacitance of 252.65 F g −1 at 0.5 A g −1 . When assembled into a symmetric supercapacitor, the device exhibits excellent cycling stability, retaining 85.11% of its initial capacitance after 10,000 cycles. This study proposes a low-cost, green, and efficient process for upgrading abundant low-grade coal into high-value-added electrode materials, offering a more economical and environmentally friendly pathway for preparing supercapacitor electrodes.
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2019
·
IF 5.128
Tengfei Yang,Congcong Liu,Chuan Li,Liyong Gan,Wenan Deng,Qingshan Niu
Nickel sulfide is regarded as one of the most promising substitutes for the best-performing disposable molybdenum catalyst in the hydrogenolysis of lignite and heavy residue, but its practical application is hindered severely by insufficient catalytic activity and a prohibitively large dosage. Herein, we report that the issues of activity and cost of nickel sulfide can be addressed simultaneously by employing a combination of iron incorporation and a dispersing strategy via oil-soluble ligands. Motivated by first-principles calculations where iron incorporation in nickel sulfide would lead to a better activity towards the rate-limiting step of hydrogenolysis compared with nickel sulfide alone, we successfully prepared a well-dispersed Fe-Ni-S catalyst by coordinating active metal salts with carboxylate ligands and a subsequent essential sulfurization. The synthesized Fe-Ni-S catalyst outperformed not only the monometallic nickel catalyst but also the commercial molybdenum catalyst in the hydrogenolysis of lignite and heavy residue, and exhibited a high conversion efficiency, hydrogen consumption, hydrogen/carbon product atomic ratio, and dispersibility of solid residues, with an economic nickel dosage of as low as ~250 μg·g −1 . Structural changes of raw coal and solid residues further confirmed the role of the Fe-Ni-S catalyst in facilitating the hydrogenolysis of lignite and heavy residue.
研究领域:
化学工程
·
催化科学
✓ 已验证
DOI
高影响因子
Journal of Energy Storage
·
2024
·
IF 8.9
Xinyang Wu,Jun Liu,Chenlei Wu,Wenjun Wu,Ying Wang,Yuqiong Zhao,Guoqiang Li,Guojie Zhang
Heteroatom-doped porous carbons are widely utilized as electrode material for electric double layer capacitors (EDLCs) due to their excellent electrochemical properties. Nevertheless, the achievement of obtaining porous carbon materials with both abundant pores and appropriate levels of heteroatom doping consistently has always been a significant hurdle. In this work, a green and economical strategy was developed for the preparation of N- and O-enriched porous carbon using a simple two-step pyrolysis process. Lignite sodium humate was used as the raw material, urea as the N source and activation aids and a low-dose KOH as the activator, as well as the urea addition ratio and coactivation temperature were explored. The optimized sample of NHAC exhibits a high specific surface area (2323.2 m 2 /g), a significant microporous volume (0.97 cm 3 /g), appropriate pore size distribution and N/O content (N 2.5 at.%, O 17.31 at.%). Consequently, NHAC electrode demonstrates a high specific capacitance of 312.75 F/g @ 0.5 A/g and a satisfactory capacitance retention of 78.18 at.% 20 A/g. Furthermore, the assembled NHAC//NHAC symmetric supercapacitor has an excellent energy density of 13.34 Wh kg −1 at 150 W kg −1 and an outstanding cycling stability of 88 % (5 A/g) after 20,000 charge/discharge cycles. This study presents a promising application of lignite humate in energy storage.
研究领域:
材料科学
·
能源存储
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE ENERGY INSTITUTE
·
2024
·
IF 5.6
Meilu Hao,Peng Liang,Miaomiao Tian,Songze Li,Yue Gao,Yaqing Zhang,Xizhuang Qin,Wenrui Zhang,Tiantian Jiao
To efficiently utilize the oxygenated structures in lignite and obtain value-added oxygenated compounds, this study proposes a low carbon cascading utilization of Zhaotong lignite (ZT) through thermal dissolution and pyrolysis. The selectivity of ethanol (ET), tetrahydrofuran (THF) and ethyl acetate (EA) for oxygenated compounds in thermal dissolution, and the enrichment of thermal dissolution-pyrolysis on oil phases were investigated. The results show that sequential thermal dissolution is selective for different oxygenated compounds in ZT. ET shows selectivity for esters at 350 °C-2 MPa and for phenols at 350 °C-6 MPa. THF and EA are selective for naphthols and esters at 350 °C-6 MPa, respectively. Compared with the single process of thermal dissolution or pyrolysis, thermal dissolution-pyrolysis can significantly increase the oil phases yield with high value-added, in which ET, THF and EA increase the oil phase yields by 24.81 wt%, 13.66 wt% and 7.90 wt%, respectively. In particular, 59.15 wt% of the oxygen is distributed in light oil, and 9.79 % phenols as well as 1.56 % esters are enriched into light oil during thermal dissolution-pyrolysis process of ET. High value-added oxygenated compounds can be selectively enriched by appropriate solvents, at the same time, the quality of pyrolysis tar can be improved and the carbon emissions could be reduced.
研究领域:
化学工程
·
能源科学
✓ 已验证
DOI
高影响因子
FUEL PROCESSING TECHNOLOGY
·
2016
·
IF 3.847
Ting-Ting Zhao,Wen-Zhi Ge,Fen Yue,Ying-Xiong Wang,Christian Marcus Pedersen,Fan-Gui Zeng,Yan Qiao
Lignite showed high capacity for reducing Cr(VI) to Cr(III) and hence removed Cr(VI) from aqueous solution, but the reduced Cr(III) cannot be released from adsorbent afterwards especially under acidic condition. In order to know why Cr(III) ions are immobilized within lignite adsorbent and how to recovery Cr species, the interaction of Cr(III) ions with lignite oxidized by Cr(VI) was studied by X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR). The data obtained from these studies indicate that Cr(III) ions are bonded to oxygenic functional groups in lignite oxidized by Cr(VI) and electrons are delocalized over -O-Cr-O- domain. It is also revealed that the O atoms of C = O and C-O groups in the adsorbent matrix are bonded to Cr(III) ions along with the decrease of electron density, while the O atoms of O -C = O group are along with the increase of electron density. Based on these important structural information, we developed a method to treat Cr-loaded lignite further and to recover the Cr species.
研究领域:
环境科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL RESEARCH
·
2022
·
IF 8.431
Wencheng Ma,Shaobo Zhang,Yiru Chen,Dan Zhong,Qinghui Du,Jinxin Li,Ru Li,Xuan Du,Jingna Zhang,Taiping Yu
In this study, lignite activated coke (LAC) was used as the carrier for the first time, Fe 3 O 4 –CuO composite metal oxide was used as the main active material, and the nano-scale magnetic supported composite metal oxide Fe 3 O 4 –CuO@LAC catalyst was synthesized for the first time, which can effectively activate the active oxygen in peroxodisulfate (PS). XRD, FTIR , BET, SEM , XPS and other analysis results showed that there was particulate matter with spherical structure on the surface of the active coke, and its diffraction peaks matched well with the characteristic peaks of Fe 3 O 4 and CuO, and it was a mesoporous structure with a specific surface area of 619.090 m 2 g −1 . By optimizing the experimental conditions, the results showed that more than 92% of hydroquinone can be removed under the conditions of hydroquinone concentration of 50 mg/L, pH = 5, adding 0.1 g/L catalyst and 3 mmol/L PS. EPR and quenching experiments proved that there were four reactive oxygen species in the reaction system ·OH, SO 4 − ·, O 2 − · and 1 O 2 . According to the degradation products of hydroquinone detected by LC-MS, the possible degradation path was deduced which laid a foundation for solving the problem of difficult treatment of phenol-containing wastewater in coal chemical industry.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2023
·
IF 6
Chong Liang,Wei Zhao,Xutang Liu,Zhijie Jiang,Fei Wang
To separate the valuable carboxylic acids (CAs) from the complicated oxidized products (OPs) of H 8 [PMo 7 V 5 O 40 ]-catalyzed lignite, systematic processes including distillation, ether extraction, acetone dissolution and separation by deep eutectic solvent (DES) were first constructed and sequentially performed. First, formic acid and acetic acid are separated in vacuum at 56 °C with the separation efficiency of 95% and 82%, respectively. Subsequently, sequential treatments of OPs by ether extraction and acetone/water dissolution are implemented to reduce the low-polarity compounds contents and fully dissolve CAs from concentrated residue. Separation results indicate that choline chloride (ChCl) shows a better separation performance compared to acetylcholine chloride and gives optimal separation efficiencies of 78.19% and 94.45% for benzenepentacarboxylic acid (BPA) and mellitic acid (MLA) within 2 h at ambient temperature, respectively. The hydrogen-bonded binding energies (BEs) formed in DES are calculated based on density functional theory, and results show that total BEs of MLA and ChCl is as high as −31.09 kcal/mol, and the next is −26.79 kcal/mol for BPA, leading to their quick and high separation efficiencies within 2 h. As a result, only MLA and BPA show the high correlation with pseudo-second-order kinetic model, and the rate constant of MLA is as high as 0.3367 g/(mg·h), which is far more than that of BPA. Additionally, the effect of hydrogen bonds on the separation of CAs follows the order of Cl∙∙∙H-O > O-H∙∙∙O-C > O-H∙∙∙O = C. Overall, this attractive strategy provides ideas for efficient separation of CAs, which will pave the way for utilization of lignite.
研究领域:
化学工程
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Cong Liu,Zhi-Ang Liu,Zhong-Qiu Liu,Hai-Ni Yang,Guo-Xiao-Yao Zhao,Yujing Liu,Anguo Ying
The preparation of carbon-based catalyst supports from low-grade lignite, followed by its self-catalytic hydrocracking to produce lignite-derived aromatic compounds, is crucial for achieving efficient lignite utilization and expanding aromatic compound sources. During lignite catalytic hydrocracking, the uncontrolled diffusive migration of active hydrogen (H*) and insufficient protection of aromatic rings reduce the yield of aromatic compounds. Using Heishan lignite as the raw material, we employed a relay process of thermal-induced self-assembly and oxidation-mediated carbon distortion for fabricating the Co 3 O 4 /AC&GC-S-600 composite material, which features an optimal hydroxyl occupancy ratio and a balanced combination of amorphous carbon/graphite carbon (AC/GC) types. The optimal hydroxyl occupancy threshold balances Co 3 O 4 dispersion and hydrophilicity, facilitating the efficient formation and directional migration of H* through synergistic interaction between Co 3 O 4 and H 2 O. The adequate threshold of AC/GC ratio regulates substrate adsorption, activation, and inhibition of aromatic hydrogenation, enhancing selective C–O bridge bond cleavage and preserving the unsaturation of aromatic rings. The synergistic regulation of dual thresholds promotes the rapid formation and the directional migration of H*, enabling efficient conversion of Heishan lignite to aromatic compounds (45.8% conversion, 80.8% selectivity) under mild conditions. Characterization techniques, experimental analyses, kinetic studies, and density functional theory calculations confirm that thermally induced self-assembly and oxidation-mediated carbon distortion are crucial for redistributing the carbon framework of the Heishan lignite matrix and regulating the optimal dual thresholds of hydroxyl occupancy and AC/GC types, which are essential for the catalytic hydrocracking of Heishan lignite to aromatic compounds. This strategy provides a scientific basis for selective catalytic production of lignite-based aromatic compounds, thereby supporting its clean and efficient utilization.
研究领域:
能源化学
·
催化科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2019
·
IF 6.97
Yafu Tang,Yuechao Yang,Dongdong Cheng,Bin Gao,Yongshan Wan,Yuncong C. Li,Yuanyuan Yao,Jiazhuo Xie,Lu Liu
To improve fertilizer use efficiency, reduce irrigation requirement, and minimize negative environmental impact, a novel large-grained-activated-lignite-slow-release fertilizer (LAF) with good water retention was developed by mechanical extrusion of activated lignite and conventional fertilizer. A 3D molybdate-sulfur hierarchical hollow nanosphere (3D-MoS2–HN) catalyst was successfully fabricated via a simple route, and the lignite was activated by 3D-MoS2–HN to increase its water-soluble humic acid content and nutrient adsorption ability. After activation, the amounts of small molecular active groups and water-soluble humic acid of activated lignite were significantly higher than those of raw lignite. The activation also increased adsorption ability of the activated lignite for nutrients. LAF prepared from the activated lignite had a preferable slow-release property and good water-holding capacity in soil. Moreover, a pot trial further demonstrated that LAF effectively improved the growth of an apple plant. With outstanding water-retention and slow-release capacities, this new fertilizer is economical and eco-friendly, and thus is promising in field applications.
研究领域:
农业科学
·
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）