SCIENCE OF THE TOTAL ENVIRONMENT
·
2021
·
IF 7.963
Wei Yi,Diweina Zheng,Xianhua Wang,Yingquan Chen,Junhao Hu,Haiping Yang,Jingai Shao,Shihong Zhang,Hanping Chen
In this study, batched hydrothermal experiments on corn stalk were conducted at 240–330 °C under CO 2 or inert (N 2 ) atmosphere. The distribution and characteristics of gaseous, solid, and liquid products were analyzed in detail to comprehensively investigate the effects of CO 2 on the hydrothermal conversion of biomass, especially on the cellulose and lignin in biomass. The results demonstrate that compared with N 2 , CO 2 slightly increased the liquid and gas yields and significantly improved the control effect of temperature on bio-oil components. Under CO 2 atmosphere, bio-oil achieved effective enrichment of ketones and phenols at 240 °C and 300 °C, respectively, and their highest relative contents reached 44.8% and 62.0%, respectively. In addition, the hydrochar obtained under CO 2 atmosphere showed higher crystallinity , which is conducive to its subsequent utilization. This study explored the feasibility of introducing CO 2 into the biomass hydrothermal process to realize the high-value utilization of biomass waste and the reuse of CO 2 .
研究领域:
能源生物学
·
环境科学
✓ 已验证
DOI
PubMed
高影响因子
FUEL
·
2020
·
IF 5.578
Ruonan Zheng,Dong Liu,Junshi Tang,Qiang Song,Qiang Yao
Coke formation during the process of in-situ combustion is affected by clay minerals, among which montmorillonite shows the most significant effect. A fixed-bed reactor was used to conduct the thermal conversion experiments of heavy oil and model compounds to reveal the mechanism of montmorillonite affecting the coke formation. Under the inert atmosphere, in the presence of montmorillonite, the temperature at which aromatic C–C groups of coke appeared decreased from 500 °C to 450 °C and polymers were formed when toluene was heated, indicating that montmorillonite catalyzed aromatization and polymerization, respectively. The increase in the supporter surface area promoted the formation of coke from pyrolysis by shortening the induction of coking. Under the oxidizing atmosphere, in the presence of montmorillonite, the initial temperature of O 2 consumed by heavy oil decreased from 270 °C to 250 °C, indicating that montmorillonite catalyzed oxygen-adding reaction. The temperature of CO x released by acetaldehyde and acetic acid decreased, and the release amounts increased, indicating that montmorillonite catalyzed decarbonylation and decarboxylation. Polymers were formed when acetaldehyde, acetic acid, ethanol, and acetone were heated, indicating that montmorillonite catalyzed polycondensation. When the oil mass fraction in the sample was within 18%, further increase in the supporter surface area did not affect the formation of coke from oxidation. The catalysis of montmorillonite was the main mechanism affecting coke formation during the thermal conversion of heavy oil under the inert and oxidizing atmospheres.
研究领域:
石油工程
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2022
·
IF 8.035
Libo Zhang,Xiao Yang,Yequan Sheng,Qiguang Huang,Zhilin Yang,Yang Shi,Xuqiang Guo,Shengbo Ge
Conversion of agricultural and forestry waste biomass into high value-added bio-oil by mild hydrothermal method is of great significance to reduce the diesel consumption and alleviate the shortage of high-quality fuel oil supply. Most of the current research focuses on the parameter adjustment in the hydrothermal process, including temperature, time, catalyst and cosolvent, but the influence of the structure of raw materials on the hydrothermal conversion activity and the properties of hydrothermal oil is less. In this study, several typical pretreatment methods (including ball milling, alkali + ball milling, urea/NaOH and NaOH + ethanol) were used to change the structural characteristics of agricultural waste cotton stalks (CS), and the treated CS were used for hydrothermal conversion at low temperature (180–220 ℃). Taking the yield of hydrothermal bio-oil as index, the results show that various pretreatment can effectively improve the hydrothermal conversion activity of CS, improve the combustion performance of hydrothermal bio-oil and adjust the composition of hydrothermal oil. The hydrothermal bio-oil obtained by NaOH + EtOH pretreatment has the best properties, the yield is 7.41 % (wt, 220 ℃, 2 h), the calorific value is 24.16 MJ/kg, and the energy recovery is 10.98 %, which is higher than untreated CS bio-oil (with yield of 3.90 wt% at 220 ℃ and 2 h, calorific value is 23.32 MJ/kg and energy recovery of 10.98 %). The research will strengthen the role of lignocellulosic raw material structure in the hydrothermal process, which will play an important role in promoting the industrialization process of hydrothermal technology in the field of biomass, especially considering the optimization of operating parameters of various raw materials in the future industrialization.
研究领域:
能源生物学
·
生物质能工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Xuan Hou,Shuhua Ma,Xiaohui Wang,Ruiping Liu,Muhammad Ibrahim
In the study of hydrothermal conversion of fly ash to calcium silicate hydrates (C–S–H), the concentration of Ca and Si in the liquid phase plays a vital role in determining the hydrothermal transformation results. This paper selected a fly ash as a research object, which can leach a high Si concentration into the solution in the hydrothermal process even in a slight alkaline solution, based on a new finding when studying the alkali dissolution kinetics of different fly ashes. To explore the effects of Ca and Si concentrations in the liquid phase on the hydrothermal transformation of fly ash to tobermorite or katoite, Na 2 SiO 3 (Na 2 O·xSiO 2 ·yH 2 O) and CaSO 4 were used to change the concentration of Si and Ca in the liquid in the hydrothermal system. Characterization methods such as XRD, SEM, infrared spectroscopy, and solid-state nuclear magnetic resonance indicated that a little more concentration of Si can promote the transformation from fly ash to tobermorite and persuade the conversion of the Si–O tetrahedron in C–S–H from Q 2 to Q 3 and Q 4 . However, too high a liquid Si concentration made the hydrothermal product change to colloidal calcium silicate. On the other hand, a high Ca concentration in the liquid was found to lead to the conversion of the hydrothermal product from tobermorite to katoite. According to the above results, the deep transformation from fly ash to tobermorite under the conditions of a low temperature of 160 °C and no extra alkali addition was achieved by the induction of a small quantity of Na 2 SiO 3 .
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2025
·Vol. 36
·期 5
·1-14
·
IF 2.8
Junlong Wang,Yimin Dai,Ling Cai,Siwen Yang,Yusong Yang,Lihui Xie,Li Wan
The frequent leakage of crude oil and the illegal discharge of industrial organic pollutants have caused serious damage to the ecological environment and the loss of valuable resources. In this paper, we introduce a sponge with magnetic and photothermal properties. Polydopamine and ferric oxide (Fe 3 O 4 ) were grafted onto the sponge, self-assembled on the three-dimensional (3D) skeleton surface by Zif material, and grafted with cetyltrimethoxysilane to make the modified sponge highly hydrophobic (water contact angle = 155°). Moreover, due to the dual photothermal conversion properties of polydopamine and ferric oxide (Fe 3 O 4 ), the modified sponge can be quickly heated to 110 °C under light (1.25 kw/m 2 ). The modified sponge demonstrated excellent crude oil adsorption capacity (44 g/g) and recyclability. Due to its magnetic properties (saturated magnetization = 4.43 emu/g), derived from the incorporation of Fe₃O₄, the sponge could be remotely controlled for adsorption. Moreover, it demonstrated the ability to continuously adsorb and collect light oil from the water surface with the aid of a peristaltic pump. The sponge also functioned as an efficient filter for separating heavy oil underwater through liquid gravity, achieving a separation efficiency of 97.2%. Therefore, this composite sponge not only presents a promising solution for crude oil spill remediation but also holds significant potential for industrial wastewater treatment, making it highly relevant for practical environmental applications.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2022
·
IF 7.968
Runhao Zhang,Miao Gong,Yujie Yan,Jiangya Ma,Huiwen Zhang
In this study, the degradation behaviour of phospholipid 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) during hydrothermal conversion (HC) and the effect of alkali additives on phosphorus forms during HC of phospholipids and different phosphorus-containing wastes were investigated. The mechanism of phosphate-alkali-directed regulation and transformation was discussed and analysed with batch hydrothermal treatment experiments and characterizations such as XRD and SEM. The obtained results showed that DOPC degradation was divided into two periods, i.e., the initial accumulation of phosphorus-containing precursors with increasing temperature, followed by complete degradation to H 3 PO 4 as treatment continued. In addition, compared with the activation of P by NaOH, Ca(OH) 2 is more favourable for the stabilization of P and the migration of non-apatite inorganic phosphorus (NAIP) to apatite inorganic phosphorus (AP). The pH and appropriate feed Ca/P molar ratio during HC determine the degree to which total phosphorus is converted to Ca-bound P. The findings reveal the mechanism of phosphate-alkali-directed regulation and transformation and provide a theoretical reference for the efficient treatment of phosphorus-containing waste and the alkali-directed production of high-phosphorus bioavailability products.
研究领域:
环境科学
·
生物化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Cleaner Production
·
2025
·
IF 10
Yafei Zhang,Yi Li,Mingzhao Cheng,Aihua Yao,Zhenzi Jing
A novel two-stage hydrothermal technology was developed to convert full sludge components into humic acid and functional minerals as key soil compositions, along with heavy metal immobilization in the synthesized minerals for environmental remediation. In the first hydrothermal stage, by simulating the underground formation mechanism of natural humic acid, the organic components in sludge were hydrothermally converted into humic acid, exhibiting significant aromaticity and porous microstructure similar to that of mineral-derived humic acid, with a high yield of 46.7% at 150 °C for 1 hour. Subsequently, the second hydrothermal stage was conducted to further convert the inorganic sludge residue into functional minerals (analcime) through hydrothermal dissolution and reconstitution at 200 °C over 6 hours. The study on the flow direction and distribution of heavy metals in sludge-derived products during hydrothermal processing quantitatively revealed that heavy metals predominantly accumulated in the inorganic sludge residue, with over 90% of Cu, 84% of Pb, and 46% of Cr being retained. These multiple heavy metals were found to be stably immobilized within the secondary hydrothermally synthesized analcime structure, with total leaching rates below 1.7%, thus minimizing their environmental impacts. Additionally, these hydrothermal products exhibited significant benefits for agricultural fertilization and environmental remediation: the humic acid enhanced soil fertility, while the functional zeolites remediated soil and water. As such, the study exhibits great potential to hydrothermally convert full sludge components into eco-friendly regenerated soil products (humic acid and analcime), paving a novel and safe way for returning sludge to nature.
研究领域:
环境科学
·
土壤学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2021
·Vol. 32
·期 10
·13382-13395
·
IF 2.478
Yang Lin,Xin Yanmei,Yao Congfei,Miao Yuqing
As an organic–inorganic hybrid material, metal organic frameworks (MOFs) has a great development prospect in the field of photocatalysis. Herein, the in situ growth of Bi-based MOF (CAU-17) on Bi 2 WO 6 was utilized to obtain Bi 2 WO 6 /CAU-17 photocatalyst by a simple solvothermal transformation method. Bi 2 WO 6 can be used both as template and Bi source. The structure and morphology of Bi 2 WO 6 /CAU-17 composites were characterized by X-ray diffraction patterns, X-ray photoelectron spectroscopy, Fourier transform infrared spectra, UV–vis diffuse reflectance absorption spectra and scanning electronic microscopy, and transmission electron microscope. The results showed Bi 2 WO 6 /CAU-17 composites were successfully constructed by growing CAU-17 in situ on Bi 2 WO 6 . Compared with pure Bi 2 WO 6 and CAU-17, Bi 2 WO 6 /CAU-17-1 h composite exhibited excellent photocatalytic activity for the degradation of Rhodamine B, and its rate constant was 0.02083 min −1 . In addition, the quantum yield and space time yield of the obtained photocatalyst were 2.56 × 10 −6 molecules/photon and 1.28 × 10 −7 molecules/photon·mg, respectively. Bi 2 WO 6 /CAU-17 also exhibits better values of the modified FOM (figure of merit). This method provides a potential opportunity for the development of in situ growth of similar MOF materials for water treatment and other possible applications in the future.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
ENERGY & FUELS
·
2018
·
IF 3.024
Ruonan Zheng,Jingjun Pan,Lijuan Chen,Junshi Tang,Dong Liu,Qiang Song,Long Chen,Qiang Yao
In situ combustion is an enhanced method to recover heavy oil. The formation and oxidation of coke are crucial to promote the combustion front. Heavy oil from China and montmorillonite, a major type of clay, were used as samples in this study. The thermogravimetric analyzer (TGA) was applied to temperature-programmed oxidation/pyrolysis experiments to study the effect of montmorillonite on the thermal conversion characteristics of heavy oil. A fixed-bed reactor was then used to obtain coke and study the effect of montmorillonite on coke properties. The characteristic temperatures of thermal conversion decreased with montmorillonite in the oxidizing atmosphere but remained unaffected in the pyrolysis atmosphere. The fuel deposition increased in both atmospheres because of montmorillonite’s strong adsorption. In the oxidizing atmosphere, the presence of montmorillonite obviously promoted the progress of coke formation and increased coke yield. The content of O was increased, and the contents of C and H were decreased in coke. The oxidation activity of coke was improved, while trailing occurred due to the blocking in the pore structures of the montmorillonite skeleton. In the pyrolysis atmosphere, the presence of montmorillonite did not influence the coke formation temperature but increased the coke yield. The content of C was increased and the contents of H and O were decreased in coke. Coke oxidation activity was reduced with the more serious trailing phenomenon. Montmorillonite significantly affected coke formation through its strong adsorption to polar components in heavy oil in both atmospheres and obvious catalysis on dehydrogenation as an acid catalyst in the pyrolysis atmosphere, while it enhanced the oxygenation due to its large surface area and catalyzed polycondensation in the oxidizing atmosphere.
研究领域:
石油工程
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2024
·
IF 10.8
Hao Han,Penglei Yan,Qingye Li,Shuyi Zhang,Binglei Jiao,Gaolei Wei,Zhao Wang,Muhan Cao,Panpan Xu,Qiao Zhang,Jinxing Chen
Upgrading the most difficult-to-recycle waste polyvinyl chloride remains a significant challenge due to the potential formation of highly toxic substances, such as polychlorinated biphenyls. Here, we introduce a paradigm shift with a mild photothermal dechlorination–carbonization process that converts waste polyvinyl chloride plastics into valuable carbon materials. Through detailed techno-economic assessment (TEA) process modeling, based on recycling 96,000 tons of plastics, we demonstrate that utilizing clean solar energy for photothermal conversion can save approximately 2.34 × 1012 kJ electricity and reduce the carbon footprint by 261,912.2 tons compared to traditional thermal-driven methods, offering clear environmental benefits. Notably, this photothermal recycling method can process more than 10 types of postconsumer and mixed waste polyvinyl chloride plastics, yielding carbon materials that exhibit excellent performance as components in sodium-ion energy storage batteries. Photothermal catalytic recycling of plastics thus emerges as a green and sustainable technology with promising applications.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2024
·
IF 8.5
Xiaotong Wang,Simin Xuan,Keying Ding,Peng Jin,Yonghua Zheng,Zhengguo Wu
Uncontrolled antibacterial, insufficient barrier and low strength are the bottlenecks of food packaging applications. Herein, Ta 4 C 3 T x nanosheet as a template was used to prepare Ta 4 C 3 T x immobilized silver nanoparticles (Ta 4 C 3 T x -AgNPs), which was compounded with nanocellulose to obtain high-strength and high barrier controllable bactericidal nanocellulose-based bioplastic packaging (CTa-Ag). The results indicated that due to the hydrogen bonding between nanocellulose and Ta 4 C 3 T x , the bridging effect of QCS (quaternized chitosan) and the filling of Ta 4 C 3 T x -AgNPs, the CTa-Ag had tightly stacked microstructure, which endowed them with excellent mechanical properties (4.0 GPa), ultra-low oxygen permeability (0.009 cm 3 /m 2 ·d·atm) and stable photothermal conversion efficiency. Importantly, the packaging exhibits the ability to control the release of antibacterial active ingredients. Moreover, the synergistic effects of controllable release of nano active factors, photothermal and photocatalysis in CTa-Ag gave it long-lasting antibacterial properties . This study brings new insights into the design and manufacture of multifunctional, controllable and long-lasting antibacterial bioplastic food packaging.
研究领域:
食品科学
·
材料科学
·
生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Materials Research Express
·
2022
·Vol. 9
·期 11
·115502
·
IF 2.025
Jiajun Miao,Yafei Zhang,Liang Yue,Xianqiang Ran,Mingzhao Cheng,Zhenzi Jing
To develop a new technology to remediate pollution sites stably and effectively, hydrothermal conversion of polluted soil (model soil) into zeolite P for in situ immobilization of Heavy Metals (HM) was carried out. Zeolite P could be synthesized from soil hydrothermally with a large range of Al/Si ratio (0.33–1.0) in 48 h at 200 °C. With immobilizing heavy metals (Cr, Zn and Cd), the crystallization of Zeolite P (Cr-ZP, Zn-ZP and Cd-ZP) was delayed with the order of Cr >Zn >Cd because the stronger the ligand effect of heavy metals have, the more heavily the nucleation and growth were influenced. During immobilization via zeolitization, a self-adaptive structuring behavior was confirmed by EDAX, BET and Rietveld refinement analyses: zeolite P structured more [AlO4]− to immobilize HM because the flexible 8-member-Ring channels (8 mRs) with higher Al/Si ratio could complex with more HM readily. The encapsulated HM occupied the original Na positions (Na1 and Na2) of zeolite P competitively because of their different cation size, e.g., the smallest Cr3+ could substitute all Na1 because Na1 is closer to the Framework Oxygen (FO); the largest Cd2+, however, substituted Na1 (9%) and Na2 (14%) evenly. The shrunken 8 mRs due to heavy metal immobilization also caused different chemical environments for different heavy metals immobilized because the smaller heavy metal cation could get closer to the framework, and also coordinated with more FO.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）