FUEL
·
2023
·
IF 7.4
Yaohong He,Yanjun Hou,Cheng Wang,Shan Wang,Yi Wei
Nowadays, the amount of waste textiles (WT) was increasing due to the increase in population, thermochemical processes owe the potential to process WT on large-scale. However, tar removal is the key to industrial thermochemical treatment. Molten carbonates pyrolysis technology is proposed to remove WT tar in this study. The result showed that molten carbonates favor catalytic reaction medium for turning tar into char and small molecular pyrolysis gases (including H 2 , CO, and CO 2 ), meanwhile, excellent heat and mass transfer performance of molten carbonates can also reinforce the reaction. 94.95 wt% of tar was removed at 550 °C with flow rate of 0.15 L/min. Molten carbonates not only promoted decarboxylation of acid in tar, but also enhanced the reaction between coke and carbon dioxide, which in return benefits lifetime of molten carbonates, so after recycling eight times, tar removal rate was still above 90 %. The kinetic study suggested that lower flow rate laid positive influence on tar elimination by contributing to mass and heat transfer inside the bubbles.
研究领域:
环境科学
·
能源工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMOSPHERE
·
2018
·
IF 4.427
Ziling Peng,Chunmei Xiong,Wei Wang,Fatang Tan,Xinyun Wang,Xueliang Qiao,Po Keung Wong
Usually, nanoscale zero-valent iron (NZVI) cannot float on water because of high density and hydrophilic surface. Herein, alkyltrimethoxysilanes with different carbon chain lengths (C1, C8 and C16) were used as “water-repellent legs” to graft onto NZVI, enduing NZVI with hydrophobic and floatable characteristics like a water strider. The hydrophobic performance of as-modified NZVI materials was found to be better when NZVI was modified by alkyltrimethoxysilane with longer carbon chain, and a large contact angle of 151.2°(>150°) was obtained in C16-NZVI, indicating the superhydrophobic characteristic of C16-NZVI. The oil-absorption experiments showed that the absorption capacity of C16-NZVI for lubricating oil reached 9.73 g/g within 30 s. After seven consecutive runs, the oil-absorption capacity of C16-NZVI still maintained at 9.26 g/g, indicating high reusability of C16-NZVI. Also, C16-NZVI exhibited excellent stability in NaCl solution without being oxidized for 32 d. Significantly, C16-NZVI possessed admirable chemical stability with high hydrophobic property in acid and alkaline solutions (pH 3–12). Considering the advantages of easy preparation, high stability and reusability, excellent oil-absorption capacity as well as magnetic recovery property, C16-NZVI is expected to have remarkable potential in the treatment of floating oil on water/seawater.
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
FUEL
·
2019
·
IF 5.128
Haimiao Yu,Yang Liu,Jiecheng Liu,Dezhen Chen
The study aims to evaluate the catalytic potential of a Ni-based catalyst supported by magnesium slag (MS) for catalytic reforming of pyrolysis volatiles from pine sawdust. The catalysts were prepared by a wet impregnation method. The effects of different parameters (Ni loading content, calcination/catalytic bed temperature and steam to carbon (S/C) ratio) on the catalytic performance were investigated. In addition, tar cracking capability and coke deposition resistance of Ni/MS catalyst and Ni/γ-Al 2 O 3 catalyst were explored under different calcination/catalytic bed temperatures. The catalysts were characterized by BET, XRD, SEM, TEM, TPO and Raman spectroscopy. The Ni/MS catalyst exhibited excellent catalytic reactivity as well as thermal stability. The best tar conversion (95.69%) and the highest hydrogen yield of 38.9 mmol/g biomass were obtained over Ni/MS catalyst under the conditions of Ni loading content = 3%, calcination/catalytic bed temperature = 800 °C, and S/C = 0.5. The interactions among Ni, Fe, Ca, and Mg formed multiple active centers (e.g., Ca 2 Fe 2 O 5 , (Ni, Mg) O solid solution and NiFe 2 O 4 ) in the catalyst to show synergistic catalysis effects, thereby jointly improving catalyst activity and coke deposition resistance. Furthermore, both amorphous carbon and graphitic carbon were formed on the used catalysts and the D/G ratio (the relative intensity ratio between the D and G bands) was positively correlated with the catalytic activity.
研究领域:
能源科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2016
·
IF 4.836
Yue Yang,Shengming Xu,Zhen Li,Jianlong Wang,Zhongwei Zhao,Zhenghe Xu
Deoiling process is a key issue for recovering metal values from spent hydrotreating catalysts. The oils can be removed with organic solvents, but the industrialized application of this method is greatly hampered by the high cost and complex processes. Despite the roasting method is simple and low-cost, it generates hardest-to-recycle impurities (CoMoO 4 or NiMoO 4 ) and enormous toxic gases. In this study, a novel and facile approach to remove oils from the spent hydrotreating catalysts is developed. Firstly, surface properties of spent catalysts are characterized to reveal the possibility of oil removal. And then, oils are removed with water solution under the conditions of 90 °C, 0.1 wt% SDS, 2.0 wt% NaOH and 10 ml/g L/S ratio for 4 h. Finally, thermal treatment and leaching tests are carried out to further explore the advantages of oil removal. The results show that no hardest-to-recycle impurity CoMoO 4 is found in XPS spectra of thermally treated samples after deoiling and molybdenum is leached completely with sodium carbonate solution. It means that the proposed deoiling method can not only remove oils simply and without enormous harmful gases generating, but also avoid the generation of detrimental impurity and promote recycling of valuable metals from spent hydrotreating catalysts.
研究领域:
化学工程
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CANADIAN JOURNAL OF CHEMICAL ENGINEERING
·
2016
·Vol. 94
·期 12
·2298-2302
·
IF 1.066
Shenwen Fang,Ying Zhu,Bin Chen,Yan Xiong,Ming Duan
In this study, a magnetic demulsifier, called M-DMEA, was prepared by “one-pot” synthesis through the pyrolysis of ferric triacetylacetonate (Fe(acac) 3 ) in DMEA 1231, which is a type of polyether demulsifier used in oil fields. The morphologies and phase compositions of the M-DMEA nanoparticles were determined by transmission electron microscopy and X-ray diffraction, respectively. The presence of surface coating was confirmed by using Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analyses (TGA). Magnetic property was measured by vibrating sample magnetometer. The demulsification of M-DMEA for treating oily wastewater produced from polymer flooding (OWPF) was investigated. It was found that the oil removal of M-DMEA reached 96.0 % at the concentration of 4.0 g/L. In addition, M-DMEA can be recycled and reused by using an external magnet. The results showed that there was a significant decrease in the oil removal after two cycles because the polymer residue remaining in OPWF, namely partially hydrolyzed polyacrylamide (HPAM), was adsorbed onto the surface of M-DMEA.
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
APPLIED ENERGY
·
2021
·
IF 9.746
Guanyi Chen,Xiaoshan Dong,Beibei Yan,Jian Li,Kunio Yoshikawa,Liguo Jiao
Tar elimination is the bottleneck which hinders the industrial application of gasification due to the risks of corrosion and blockage in downstream components. Tar production decreases the energy efficiency of gasification systems. The steam reforming is attractive for tar treatment, but the high reaction temperature limits its applications. Photothermal catalysis has the potential to decompose organic pollutants, and it is expected to improve tar removal and reduce the reaction temperature. So, the photothermal steam reforming of toluene was performed to evaluate the toluene conversion. The effects of the toluene concentration, the temperature, the steam to carbon ratio, and the ultraviolet light intensity were investigated. The results showed that, compared with the thermal steam reforming, the photothermal steam reforming could significantly improve the conversion of toluene and promote the formation of gaseous products, especially H 2 . At 600 °C, the conversion of toluene in the photothermal steam reforming was 90.1%, which was 16.3% higher than that in the thermal steam reforming. Moreover, the mechanisms of the photothermal steam reforming were revealed. The introduction of the ultraviolet irradiation could strongly promote the toluene decomposition and alter the reaction pathways. The carbon deposition and agglomeration of the catalyst were inhibited in photothermal steam reforming. Meanwhile, the toluene removal performance and the energy consumption were compared in photothermal and thermal steam reforming. The potential applications of photothermal catalytic tar removal were also described. These findings proposed a novel approach for low-cost but high-efficiency biomass tar removal, thus promoting the clean utilization of biomass energy.
研究领域:
能源科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2024
·
IF 12.2
Maolin Tian,Hongtao Liu,Jian Cui,Yaqing Weng,Xueli Wang,Erkang Feng,Wenjie Zhang,Caifang Cao,Jiawei Wen,Guoyong Huang,Shengming Xu
The removal of crude oil from spent hydrodesulfurization catalysts constitutes the preliminary stage in the recovery process of valuable metals. However, the traditional roasting method for the removal exhibits massive limitations. In view of this, the present study used an ultrasound-assisted surfactant cleaning method to remove crude oil from spent hydrodesulfurization catalysts, which demonstrated effectiveness. Furthermore, the study investigated the mechanism governing the process with calculation and experiments, so as to provide a comprehensive understanding of the cleaning method’s efficacy. The surfactant selection was predicated on the performance in the IFT test, with SDBS and TX-100 finally being chosen. Subsequent calculations and analysis were then conducted to elucidate their frontier molecular orbitals , electrostatic potential , and polarity. It has been found that both SDBS and TX-100 possess the smallest LUMO-HOMO energy gap (ΔE), registering at 4.91 eV and 4.80 eV, respectively, and presenting the highest interfacial reactivity. The hydrophilic structure in the surfactant regulates the wettability of the oil-water interface, and the long-chain alkanes have excellent non-polar properties that promote the dissolution of crude oil. The ultrasonic-assisted process further improves the interface properties and enhances the oil removal effect. Surprisingly, the crude oil residue was reduced to 0.25% under optimal conditions. The final phase entailed the techno-economic evaluation of the entire process, revealing that, in comparison to the roasting method, this process saves $0.38 per kilogram of spent HDS catalyst, with the advantages of operational simplicity and emission-free. Generally, this study shed new light on the realization of efficient oil removal, with the salience of green, sustainable, and economical.
研究领域:
化学工程
·
环境科学
·
催化材料
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
·
2021
·
IF 5.541
Haimiao Yu,Jiecheng Liu,Haojie Yang
A novel magnesium slag (MS) supported nickel-based catalysts (Ni/MS) was prepared and tested in catalytic reforming of volatiles derived from the pyrolysis of biomass components (cellulose, hemicellulose and lignin) and two biomass feedstocks (pine and straw). The physical and chemical properties of catalysts were characterized by XRD, TPR, BET, TEM, TPO-TGA and Raman spectroscopy. Ni/MS catalyst showed a higher tar removal efficiency than conventional Ni/γ-Al 2 O 3 under the same Ni loading. The tar conversion of cellulose hemicellulose and lignin reached 94.8 %, 92.0 % and 89.4 %, respectively over Ni/MS catalyst. In addition, the lignin content of the biomass feedstock appreciably affected the yield and dew point of tar. The highest increment in gas and H 2 yield (increased by 39.0 % and 106.4 %, respectively) was observed in cellulose. The highest decrement in tar dew point (from 166.4 ℃ to 53.0 ℃) was observed in hemicellulose. The excellent tar removal of Ni/MS was attributed to the metallic Ni and Ni-Fe alloy on catalyst surface. Besides, the MgO and Fe 2 O 3 phases in the support can retard the carbon deposition during the reaction. The results of this study are expected to provide insightful guidance for the application of Ni/MS catalysts for pyrolysis/gasification of biomass.
研究领域:
能源与环境科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
WASTE MANAGEMENT
·
2018
·
IF 4.723
Yue Yang,Tiantian Cao,Yong Xiong,GuoYong Huang,Wenqiang Wang,Qi Liu,Shengming Xu
Deoiling enjoys great significance in recycling and landfill of spent hydrotreating (HDT) catalyst. In this study, a novel approach for oil removal from spent HDT catalyst with assistance of ultrasound was developed. The effects of variables on oil removal were investigated by response surface methodology and central composite design method. The oil removal efficiency reaches 96.03 ± 0.82% under the optimum conditions of liquid-solid ratio 16.00 ml·g −1 , 75 °C, sodium hydroxide dosage 3.88 wt%, and 40 kHz ultrasonic irradiation for 3.25 h. Under the optimum conditions, the contact angle of spent catalyst is 98.7° before oil removal, and then reduces to 57.2° after deoiling with the help of ultrasound, but turns to 72° after deoiling in the absence of ultrasound, which further verifies that the oil removal efficiency can be improved by ultrasound. Compared to traditional extraction or hydrothermal methods for removing oil from spent catalyst, the proposed approach introduced ultrasonic force field to enhance oil removal efficiency without adding organic solvent or surfactant.
研究领域:
化学工程
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Materials Chemistry A
·
2021
·Vol. 9
·期 46
·26127-26134
·
IF 12.732
Xiangyu Li,Qilin Gui,Yen Wei,Lin Feng
Superwetting porous membranes are highly desirable for purifying oily wastewater discharged from industrial and domestic sources. However, the sustainability of this technology remains challenging due to its incapability of eliminating residual soluble oils in post-purified water. The critical limitation that the filtrate cannot meet stringent emission standards is neglected by previously reported studies. Herein, nanostructured superwettable skins are developed to provide filtration membranes with the comprehensive performance of soluble oil removal. According to a newly proposed separation mechanism of unlockable-hydration hydrophobic assembly, membranes are employed to separate various surfactant stabilized oil-in-water emulsions with ultralow residual oil content (<0.5 mg L−1), superior permeation flux (∼1400 L m−2 h−1), and robust reusability for long-term work solely under the driving force of gravity (∼1.5 kPa). This study should provide distinctive insights into the functional wetting modification and pioneer a promising strategy to design high-performance separation materials for thorough oily wastewater remediation.
研究领域:
环境科学
·
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2020
·
IF 6.182
Xiao Miao,Changqing Zhu,Guina Ren,Xiaohui Sun,Yuchao Li
The availability of two-dimensional composite photocatalyst materials under rapid, large-scale and mild conditions is a bottleneck for the application of water pollution treatment materials. In this paper, a superhydrophobic-BiOBr composite (WCA = 158°) with size of 0.5 m × 0.5 m was prepared by spraying and combustion methods within 1 h. The obtained fabric has selective oil removal performance and can be used for degrading the water-soluble pollutant under outdoor exposure to sunlight irradiation. The degradation efficiency of rhodamine B can reach 97.4% after 140 min. This excellent light activity can be attributed to the higher roughness requirements of the superhydrophobic fabric that the catalyst exposed area be increased. This work discusses not only the photodegradation active species ( O 2 − ) as well as the valence band (3.025 eV.) and conduction band (0.315 eV) information, but also the mechanical stability and verification of large-scale preparation. It also provides a new solution for the practical application of photodegradable materials.
研究领域:
材料科学
·
环境科学
·
表面化学
✓ 已验证
产品关联
DOI
高影响因子
PETROLEUM SCIENCE AND TECHNOLOGY
·
2023
·
IF 1.5
Huili Zhang,Hailin Yu,Hongsheng Liu
Carbon nanotubes (CNTs), as a new type of carbon material with complete molecular structure, have great application potential in the field of nanocomposites. In this study, carbon nanotubes were first surface modified to give them good hydrophilicity. Subsequently, the nanocomposite coagulant (PASS-T) with different modified CNTs (m-CNTs) contents was prepared by alkaline titration method. The CNT, m-CNT, PASS and PASS-T were characterized by FTIR, XRD and XRF. Then the coagulant was applied to oily sewage, and the coagulation results showed that the PASS-T (0.1%) had the best oil reduction rate (92%) and turbidity reduction rate (97%). Appropriate addition of m-CNT can increase the local concentration of coagulant at the molecular level, making the flocs of oily sewage larger. It can be found by SEM that PASS-T produces large and knotted flocs in oily sewage. Finally, the residual turbidity and oil removal rate of the different coagulants were statistically analyzed.
研究领域:
材料科学
·
环境工程
✓ 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）