Asia-Pacific Journal of Chemical Engineering
·
2023
·
IF 1.8
Kai Fei,Zhuo Yi Dong,Li Shi,Xuan Meng,Naiwang Liu
Transformer oil plays a critical role in ensuring the insulation and normal operation of power transformers. However, during operation, the transformer oil would undergo oxidation and degradation, leading to the formation of acids and polar compounds that increase its acidity and degrade its performance. Hence, the recycling and regeneration of aged transformer oil is an essential practice in transformer maintenance, contributing significantly to the extension of a transformer's operational lifespan and the reduction of potential risks. Adsorption separation is a preferred method for regeneration, offering simplicity and high efficiency. This study focuses on impregnated γ-Al 2 O 3 as an adsorbent for acidity removal in waste transformer oil. We conducted static adsorption experiments to investigate the optimal loading amount of the active component and the best calcination temperature for acid removal. XRD technique is employed to monitor the phase changes of the carrier during the calcination process. BET analysis is used to observe variations in the specific surface area and pore volume of the adsorbent during the modification process. DTG-TGA is utilized to assess the weight loss during the calcination process. FTIR is employed to observe changes in functional groups during modification and adsorption processes. Along with these investigations, a study is also carried out to assess the dynamic acid removal performance of the acid-removing adsorbent loaded into a fixed bed. The findings contribute to the development of sustainable methods for regenerating transformer oil, ensuring efficient and environmentally friendly operations.
研究领域:
化学工程
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环境科学
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DOI
高影响因子
CATALYSIS LETTERS
·
2018
·Vol. 148
·期 11
·3402-3412
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IF 2.911
Bao Qiang,Qi Hui,Zhang Chunlei,Ning Chunli,Zhang Yi,Jiang Ye,Wu Yifan,Gui Wenying,Wang Zhenlu
Abstract In this work, titanium-doped mesoporous Al 2 O 3 (γ-Ti–Al 2 O 3 ) was prepared by an evaporation-induced self-assembly method and used as a carrier of Ba/γ-Ti–Al 2 O 3 catalyst to catalyze the aldol condensation of methyl acetate with formaldehyde to methyl acrylate in a fixed-bed reactor. The catalysts were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, N 2 adsorption–desorption, pyridine absorption performed via Fourier transform infrared spectroscope (Py-IR), and NH 3 and CO 2 temperature-programmed desorption (NH 3 and CO 2 -TPD). Experimental results indicated that the doping of the titanium species into the frame work of mesoporous Al 2 O 3 (γ-Ti–Al 2 O 3 ) had a significant influence on the catalytic activity via modifying the acid–base surface properties of the catalyst. Furthermore, the Ba/γ-Ti–Al 2 O 3 catalyst demonstrated excellent catalytic performance, with a methyl acetate conversion rate of 50% and methyl acrylate selectivity up to 90.2%. Compared with the Ba/Al 2 O 3 catalyst, the Ba/γ-Ti–Al 2 O 3 catalyst had better catalytic activity, stability and potential for practical application, which was likely due to an increased number of Lewis acid sites, especially the medium acid sites. Graphical Abstract Barium supported mesoporous γ-Ti–Al 2 O 3 catalyst was found to be an effective catalyst for vapor phase aldol condensation of methyl acetate with formaldehyde.
研究领域:
催化化学
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材料科学
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DOI
高影响因子
CATALYSIS TODAY
·
2016
·
IF 4.312
Dapeng Liu,Anjie Wang,Chenguang Liu,Roel Prins
Bulk Ni 2 P and Al 2 O 3 -supported Ni 2 P were prepared at low phosphidation temperature (300 or 330 °C) from nickel nitrate, oxide, sulfate, chloride, and acetate as nickel source and ammonium and sodium hypophosphite as well as hypophosphoric acid as phosphorus source. The hypophosphite source was positioned up-flow of the nickel source in an oven and flowing N2 gas transported the phosphine formed in the decomposition of hypophosphite to the nickel compound. X-ray diffraction, N2 adsorption-desorption, thermogravimetry and differential scanning calorimetry, temperature-programmed reduction in H 2 , and transmission electron microscopy, field emission scanning electron microscopy, CO chemisorption, and solid-state 31 P nuclear magnetic resonance were used to study the bulk and supported Ni 2 P. Whereas unsupported nickel nitrate, sulfate, chloride, and oxide led to impure Ni 2 P, nickel acetate gave pure Ni 2 P. Ni 2 P/Al 2 O 3 catalysts were therefore prepared from nickel acetate and their activity was studied in the hydrodesulfurization of dibenzothiophene. Separating the hypophosphite from the nickel compound has the advantage that the phosphate formed in the disproportionation of hypophosphite does not reach the Al 2 O 3 -supported Ni compound and cannot block the pores of the support. Ni 2 P is formed by sequential reduction and phosphidation reactions and therefore its preparation demands careful adjustment of the synthesis conditions. Insufficient PH 3 leads to Ni and Ni 12 P 5 side products and too much PH 3 to Ni 5 P 4 , which all have a lower HDS activity than Ni 2 P.
研究领域:
化学工程
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催化材料科学
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DOI
高影响因子
CHINESE JOURNAL OF CHEMICAL PHYSICS
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2016
·Vol. 29
·期 5
·617-622
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IF 0.496
Tang Wen-wu,Zhang Xing-hua,Zhang Qi,Wang Tie-jun,Ma Long-long
Ni-based catalysts supported on different supports ( α -Al 2 O 3 , γ -Al 2 O 3 , SiO 2 , TiO 2 , and ZrO 2 ) were prepared by impregnation. Effects of supports on catalytic performance were tested using hydrodeoxygenation reaction (HDO) of anisole as model reaction. Ni/ α -Al 2 O 3 was found to be the highest active catalyst for HDO of anisole. Under the optimal conditions, the anisole conversion is 93.25% and the hydrocarbon yield is 90.47%. Catalyst characterization using H 2 -TPD method demonstrates that Ni/ α -Al 2 O 3 catalyst possesses more amount of active metal Ni than those of other investigated catalysts, which can enhance the catalytic activity for hydrogenation. Furthermore, it is found that the Ni/ α -Al 2 O 3 catalyst has excellent repeatability, and the carbon deposited on the surface of catalyst is negligible.
研究领域:
催化化学
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材料科学
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DOI
高影响因子
FUEL
·
2019
·
IF 5.128
Lina Han,Weiguo Ren,Bing Wang,Xingxing He,Lingjun Ma,Qihuang Huo,Jiancheng Wang,Weiren Bao,Liping Chang
In this work, a novel method is introduced to activate coal gangue (CG) for extraction of Si and Al species. The activation experiments were carried out using a stainless steel tube reactor (17 mL) and an autoclave reactor (1000 mL). Firstly, CG was activated by supercritical water added with alkali. It was found that the kaolinite phase of raw CG could be transformed into cancrinite, sodalite and kalsilite by using NaOH, Na 2 CO 3 and KOH as activators, respectively. Secondly, silica (SiO 2 ) and alumina (Al 2 O 3 ) were prepared by acid and alkali combination method. The extraction rates of Al 3+ and Si 4+ from the activated CG using KOH as activator were as high as 78.9% and 69.2%, respectively. The purity of SiO 2 and Al 2 O 3 products were 96.2% and 99.3%, respectively. The as-synthesized SiO 2 both from 17 mL and 1000 mL reactor exhibited very high specific surface areas of 710.0 m 2 ·g −1 and 872.8 m 2 ·g −1 , respectively. In addition, the SiO 2 after hydrophobic modification displayed excellent absorption selectivity for xylene.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
JOURNAL OF PLASTIC FILM & SHEETING
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2019
·
IF 1.714
Rui Zhang,Tongqing Zhang,Youfeng Cai,Xuyang Zhu,Qiong Han,Yu Li,Yi Liu,Ailian Wang,Guihong Lan
In this work, composite nanofiber membranes were prepared by adding modified nano-sized Al2O3-particles to a polyvinylidene fluoride (PVDF) solution (17 wt %) through an electrospinning process. The Al2O3 content affected the spun membrane performance, such as hydrophilicity, bovine serum albumin (BSA) rejection rate and anti-fouling properties were examined in detail. UF (experiment with an ultrafiltration cup) experiment was used to measure how the membrane water flux changed. This test showed that the nanoparticle affect was remarkable, the pure water flux was 4635 L•m−2•h−1 in 2% Al2O3/PVDF membrane versus 3546 L•m−2•h−1 for the membrane without nanoparticles. Contact angle was used to determine the hydrophilicity change of membranes. The results demonstrate that the modified membrane hydrophilicity was enhanced dramatically the contact angle of composite membrane with 2% Al2O3 was 56.34° versus 85.64° for the pristine PVDF membrane. The roughness and surface structure were measured by atomic force microscope (AFM) and electron microscopy (SEM). There were clear fibers in SEM images and the membrane surface roughness was heightened by adding nanoparticles. The rejection rate was investigated by UV spectrophotometer and the porosity was measured using a dry-wet weight method. The spun membrane rejection rate was 95.4%. Thermo gravimetric Analysis (TGA) and Fourier transform infrared spectroscopy (FT-IR) were used to study how nano-Al2O3 particles affected the membrane structure. More importantly, the Al2O3/PVDF spun membrane displayed an outstanding anti-fouling property. To sum up, this composite spun membrane shows a remarkable efficiency in the test and could be an ideal candidate for water treatment.
研究领域:
材料科学
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环境工程
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膜技术
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产品关联
DOI
高影响因子
FUEL
·
2025
·
IF 7.5
Hong-Hui Gong,Xian-Yong Wei,Wen-Long Mo,Zhi-Min Zong,Guang-Hui Liu,Pei Liu,Kun-Peng Jiao
NiCs/Al 2 O 3 with medium-strong alkaline and the contents of Ni and Cs of 26.55 wt% and 0.02 wt%, respectively, was prepared by a three-step method and characterized with multiple tools. Oxydibenzene (ODB) and benzyloxybenzene (BOB) were used as low-rank coal-related model compounds and their catalytic hydroconversion (CHC) were investigated over NiCs/Al 2 O 3. Under mild conditions (MCs), NiCs/Al 2 O 3 can effectively activate H 2 to biatomic active hydrogen (H···H) and part of H···H can be effectively split to relative mobile H - and immobile H + on the NiCs/Al 2 O 3 surface. Both ODB and BOB can be completely converted and full hydrogenation (FH) of the benzene ring (BR) in −O-BR is the first step for the CHC of both ODB and BOB via H···H transfer to the BR under MCs. Subsequently, H - transfer to an ipso -carbon (IC) in the resulting oxydicyclohexane from the FH of ODB cleaves an −O-CH< bond to produce cyclohexane (CH I ) and cyclohexyloxy anion (CHOA), which abstracts H + from H···H to afford cyclohexanol (CH II ) followed by H - transfer to the IC in CH II and subsequent HO – release to yield CH I . As a result, CH I is the only final product from the CHC of ODB. In contrast, H - transfer preferentially proceeds to the carbon atom in the –CH 2 - of the resulting benzyloxycyclohexane from the FH of the BR in −O-BR of BOB to produce toluene and CHOA followed by the FH of toluene to get methylcyclohexane and the H + abstraction by CHOA from H···H to obtain CH II . Moreover, NiCs/Al 2 O 3 shows a distinguished recyclability and repeatability.
研究领域:
化学工程
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催化科学
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DOI
高影响因子
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
·
2021
·Vol. 168
·期 10
·103508
·
IF 4.316
Donghua Tian,Mingyong Wang,Jingxiu Wang,Jiguo Tu,Shuqiang Jiao
USTB technology is widely considered as a low-cost and environmentally-friendly method for titanium extraction from a consumable TiCxOy anode. It is expected to directly prepare TiCxOy by selective carbothermal reduction of titanium ores, not pure TiO2. However, impurities in titanium ores, particularly Al2O3, may affect the electrochemical dissolution of TiCxOy and Ti extraction. In this work, the effects of Al2O3 impurity on the preparation and dissolution behaviors of Ti2CO are studied. It is found that the existence form of Al2O3 is not changed during carbothermal reduction. With the increase of Al2O3 content, the conductivity of Ti2CO anode slightly decreases from 143.1 to 131.6 S cm−1 and the anodic polarization curves of Ti2CO@Al2O3 shifts to the positive direction due to the increase of dissolution resistances. Al2O3 in Ti2CO@Al2O3 anode will drop into molten salts to form anode slime during USTB process. On both liquid Zn and solid nickel cathodes, Ti is electrodeposited, which is not affected by Al2O3 impurity. Therefore, it is confirmed that typical Al2O3 impurity has no obvious effect on the electrochemical dissolution of Ti2CO anode and Ti extraction. The advanced USTB process is expectedly developed by the selective carbothermal reduction of titanium ores to prepare Ti2CO anode.
研究领域:
冶金学
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材料科学
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DOI
高影响因子
ZEITSCHRIFT FUR PHYSIKALISCHE CHEMIE-INTERNATIONAL JOURNAL OF RESEARCH IN PHYSICAL CHEMISTRY & CHEMICAL PHYSICS
·
2023
·Vol. 237
·期 7
·969-980
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IF 2.5
Waquar Ahmed Khokhar,Atef El Jery,Adeel Ahmed,Mouataz Aldrdery,Danish Ahmed,Muhammad Usman,Muhammad Rafiq,Raza Ullah,Muhammad Khurram Tufail
Highly conductive and stable β″-Al 2 O 3 electrolyte powder is achieved via the solid-state reaction technique when sintered at 1200 °C, 1250 °C, 1300 °C, 1350 °C, and 1400 °C temperature, correspondingly. The findings show that the ionic conductivity has improved slightly from 1200 °C to 1400 °C. As the sintering temperature is increased, the EIS curve shows a short curve of resistance. A maximum ionic conductivity of 7.07 × 10 −4 S cm −2 is achieved at 1400 °C (1800 Ω). This is caused by the large β″ contents in Al 2 O 3 , as inspected by the X-ray diffraction results. Furthermore, the morphology of Al 2 O 3 shows less porosity and denser particles within the powder.
研究领域:
材料科学
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电化学
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DOI
高影响因子
CATALYSIS LETTERS
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2021
·Vol. 153
·期 6
·1666-1675
·
IF 3.186
Wang Yuan,Liu Shanshan,Zhang Yidong,Guo Qirui
Hydrogenation of biomass-derived furfuryl alcohol to widely used tetrahydrofurfuryl alcohol is an important industrial route, which however calls for a more efficient catalyst. In this work, a highly selective and stable Ni-C-Al 2 O 3 catalyst for furfuryl alcohol hydrogenation to tetrahydrofurfuryl alcohol is reported. The catalyst precursor is prepared by in-situ growth of Ni-based metal organic frameworks (Ni-BTC) on Al 2 O 3 and then the precursor undergoes thermal decomposition to obtain the catalyst directly. For comparison, Ni-C/Al 2 O 3 acquired from pyrolysis of physically mixed Ni-MOFs with Al 2 O 3 and Ni/Al 2 O 3 prepared by impregnation method are also tested as the hydrogenation catalysts. The prepared catalysts are characterized by a series of techniques, including XRD, FT-IR, TG, TEM, SEM, XPS and BET to reveal the relationship between the catalysts structure and their performance. The results show that small metal Ni particle size and appropriate interaction between Ni and the support, which benefit from the in-situ preparation method are key factors that ensure the high furfuryl alcohol conversion (99.8%) and high selectivity to tetrahydrofurfuryl alcohol (98.2%) at moderate reaction conditions (120 °C, 30 min, 4 MPa H 2 ). Graphical Abstract
研究领域:
催化化学
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材料科学
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生物质转化
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产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Qibao Yang,Shaobai Sang,Yawei Li,Tianbin Zhu,Heng Wang
The development of highly oxidation-protective and stable coatings is crucial for significantly reducing the oxidation of 06Ni9DR alloy steels during heating before hot rolling, thereby enabling the products with superior surface quality. In this study, three types of coatings—Al 2 O 3 -glass coating, a 10 wt% NiO-90 wt% Al 2 O 3 ceramic coating, and a double-layer coating Al 2 O 3 -glass top layer and NiO-Al 2 O 3 ceramic bottom layer)—were prepared, and their oxidation protection and underlying mechanisms were systematically investigated. The results revealed that the oxidation protection ratio of the glass coating sharply decreased from 96.6 % for 10 min to 44.9 % for 180 min at 1200 °C. In contrast, the oxidation protection of the ceramic coating increased slightly with the oxidation time. Notably, the excellent oxidation protection ratio of the double-layer coating was obtained as 86.2 % for 180 min. The rapid densification of the Al 2 O 3 -glass layer in the double-layer design provided good oxidation protection and significantly reduced the formation of iron oxides in the initial oxidation stage; NiO-Al 2 O 3 ceramic layer reacted with Fe 2+ to form a relatively dense composite spinel barrier layer, which further improved the thermal stability of the Al 2 O 3 -glass layer, and greatly enhanced the oxidation protection and stability of the double-layer coating.
研究领域:
材料科学
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冶金学
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表面工程
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陶瓷材料
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高温氧化
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED POWDER TECHNOLOGY
·
2022
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IF 4.969
He Zhang,Jun-Ru Liu,Zhi-Bo Li,Xiao-Chun Deng,Guo-Hua Zhang,Kuo-Chih Chou
In this study, high-performance fine-grained W-Cu sintered blocks with the addition of dispersed Al 2 O 3 particles were successfully produced by low temperature liquid-phase sintering, using the raw material of ultrafine W-Cu alloy powder. The ultrafine W-Cu alloy powder was obtained by a two-step reduction process composed of stages of carbothermal reaction and hydrogen deep deoxidation. The fine Al 2 O 3 grains with uniform distribution in W-Cu alloy were introduced by spray method, leading to the decrease of W grain size and W-W connectivity. The relative densities of all sintered blocks were>97%, and a higher degree of densification ensures that the alloy has excellent comprehensive properties. With the increase of Al 2 O 3 content, W grain size and W-W connectivity of sintered W-Cu samples decrease from 664 nm to 472 nm and 0.2 to 0.14, respectively. The W-Cu alloy with the ultimate tensile strength of 415 MPa and the highest elongation of 7.22% was obtained when the addition amount of Al 2 O 3 was 0.5 wt%. At the same time, it also possessed the maximum bending strength of 1028 MPa and microhardness of 312 HV, respectively. In addition, due to the good network structure of Cu and uniform three-phase distribution, the sintered samples had excellent conductivity and compressive strength.
研究领域:
材料科学
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冶金工程
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）