CHEMICAL ENGINEERING SCIENCE
·
2024
·
IF 4.1
Xiaolin Bi,Nan Zhao,Meina Guo,Weihua Zhang,Fengping Zhou,Wuming Xie,Ruigang Wang
Roxarsone (ROX), a livestock growth enhancer, poses environmental and health hazards due to its remarkable stability, making traditional degradation methods ineffective. To tackle this issue, a novel Fenton-like composite, composed of nanoscale zero-valent iron supported on γ-aluminum oxide (nZVI/γ-Al 2 O 3 ), was synthesized to boost ROX degradation. Results demonstrated nearly complete mineralization of the ROX organic matrix within just 180 min, facilitated by the Lewis acidity sites of γ-Al 2 O 3 . Significantly, this composite exhibited selective adsorption of released AsO 4 3− ions on its surface, forming FeAsO 4 and Fe-As-Al complexes. It also established an internal redox cycle involving Fe(0), Fe(II), and Fe(III), ensuring a continuous and efficient generation of primary reactive oxygen species (·OH and O 2 ·− ). Thus, a simultaneous redox process occurred on the composite surface can be attributed to the synergy of the reducibility of nZVI and the oxidation catalyzed by ·OH and O 2 ·− . Initially, the nitro group of ROX was reduced by nZVI, forming more hydrophilic o-aminophenol, favoring subsequent oxidation and mineralization. Simultaneously, the As-C bonds in ROX were oxidized, yielding AsO 4 3− , which was subsequently adsorbed over extended reaction times. This innovative approach offers a potential solution for treating wastewater contaminated with metalloid-organic composite pollutants, addressing the environmental and health concerns associated with ROX residues.
研究领域:
环境科学
·
化学
·
生物学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2015
·
IF 2.711
Lei Liu,Shi-Zhong Luo,Bin Wang,ZhanHu Guo
The interactions between poly(acrylic acid) (PAA) and alumina have been widely investigated. In this study, the pattern of small molecular weight PAA ( M W 3000) interaction with γ-alumina has been dissected. The alumina/PAA hybrids were prepared at pH 4.0, 5.5, and 7.0, respectively. Nitrogen absorption–desorption analysis, Fourier transform infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, and elemental analysis were conducted to illustrate the characteristics of the hybrids. At pH 4.0, the coiled PAA conformation yielded polymer adsorption primarily on alumina outer surface. At higher pH values, the more stretched PAA molecules were able to infiltrate inside the alumina pores. The phenomenon is explained by the polymer chain reptation motion model. Coiled polymer chains are not oriented enough to penetrate the oxide pore channels. In contrary, stretched polymer chains are more likely to move along the pore channels.
研究领域:
材料科学
·
表面化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2025
·
IF 11.3
Qiuyu Chen,Yongyi Zhang,Haiwang Liu,Peng Liu,Xinxin Ye,Xing Xia,Xiangwei Wu
Straw-derived dissolved organic matter (DOM) is widespread in farmland soils, but the relationship between straw-derived DOM and As in their co-sorption on minerals and the underlying mechanisms remain unclear. Here, batch experiments and spectroscopic analyses were employed to investigate the co-sorption of straw-derived DOM and As(III/V) on γ-Al 2 O 3 . Results showed a trade-off between the As(III/V) and DOM immobilization on γ-Al 2 O 3 under different pH levels, which was caused by competitive sorption. The rape straw-derived DOM (DOM_Ra) exhibited a stronger inhibition on As(III/V) sorption than rice straw-derived DOM (DOM_Ri). This could be due to more aromatic fractions in the DOM_Ra and DOM_Ri, which were preferentially sorbed by γ-Al 2 O 3 . In turn, the preferential sorption of aromatic DOM components was weakened by As(V) sorption, which, however, was not found in As(III) and DOM co-sorption. Furthermore, spectral results indicated that carboxylic groups on the sorbed DOM could provide additional binding sites for As(III/V) to form ternary complexes, but its role was overwhelmed by the DOM competitive sorption, which ultimately exhibited the inhibitory effect of DOM on As(III/V) sorption. These findings enhance the fundamental understanding of the co-sorption of As(III/V) and DOM on soil minerals and contribute to predicting As mobility and OM stability in As-contaminated farmlands with straw return.
研究领域:
环境科学
·
土壤化学
·
农业生态学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CERAMICS INTERNATIONAL
·
2018
·
IF 3.057
Xiuxiu Zou,Peng Wang,Zongde Wang,Guorong Fan,Shangxing Chen,Shengliang Liao,Hongyan Si,Meijuan Lu
The discovery that γ -alumina can be prepared at lower calcination temperature from an ammonium aluminum carbonate hydroxide (AACH) precursor templated with rosinyl trimethyl ammonium chloride has led to the assumption that Cl - is capable of lowering the temperature of the phase transformation of AACH to γ -alumina. To verify this hypothesis, several chlorides were introduced into the calcination process of the AACH precursor. The samples were characterized using X-ray diffraction, thermogravimetry and differential scanning calorimetry as well as X-ray photoelectron spectroscopy. The results showed that Cl - has great effects on the crystallinity of γ -alumina obtained by the calcination of AACH. The effects varied with the type, dosage and introduction method of the particular chloride. It was also found that Cl - began to take effect only after the AACH had been decomposed to form amorphous alumina . Therefore, the true function of Cl - is to decrease the temperature of the phase transformation from the amorphous phase to γ -alumina: the phase transformation temperature decreases by as much as 115 K.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Catalysts
·
2023
·Vol. 13
·期 6
·994
·
IF 3.9
Jiangang Lv,Di Wang,Luming Peng,Xuefeng Guo,Weiping Ding,Weimin Yang
Highly efficient and stable catalysts are among the key factors in industrial ethanol dehydration to ethylene. Among the widely studied catalysts, alumina is the most suitable for industrial application. In this study, novel gamma alumina was synthesized by solvent protection and a hydrothermal procedure. HRTEM, XRD, FT-IR, NH3-TPD, H-D exchange, and29Si MAS NMR were employed to compare the difference in physicochemical properties between the novel gamma alumina and commercial alumina. Characterization results show that the as-synthesized novel gamma alumina mainly exposes the high-energy crystal plane (111) while the commercial alumina mainly exposes the thermostatically stable (110) crystal plane. The dominating (111) plane, according to the characterizations, endows the novel gamma alumina with a higher density of surface hydroxyl groups, higher acid content, and higher surface energy compared to the commercial alumina. The catalytic performance of the two catalysts for industrial ethanol dehydration to ethylene was studied. The novel (111) plane-exposed alumina showed a higher yield of ethylene than commercial alumina under the same reaction conditions. This could be related to the difference in atomic arrangement and the unsaturated aluminum coordination of different crystal planes. Stability testing under severe reaction conditions (450 °C, 1 MPa, 4 h−1) indicates that novel gamma alumina shows better stability (catalyst life cycle increased by 50%) and produces less acetaldehyde as a byproduct. The effects of steam treatment on the catalytic performance were further investigated. The surface acidity and the catalytic performance of novel gamma alumina present a volcanic curve with the increase in steam treatment temperature. Under the optimal water vapor treatment temperature of 650 °C, the conversion of ethanol and selectivity of ethylene were both higher than 99%.
研究领域:
化学工程
·
材料科学
✓ 已验证
DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2015
·
IF 3.453
Xianfu Chen,Wei Zhang,Yuqing Lin,Yuanyuan Cai,Minghui Qiu,Yiqun Fan
Membrane technology has become a low-cost and high-efficiency separation technology for industrial processes over the past decennia. The colloidal route is an environmentally benign process for the preparation of ceramic membranes by using water as solvent. A stable, colloidal boehmite sol with an average particle size of 16 nm was prepared from aluminum tri-sec-butoxide using water as a solvent in the pH range of 3–4. Acetic acid was used as the peptizing agent instead of nitric acid. The stable sol was used to fabricate γ-alumina nanofiltration membranes on α-alumina microfiltration substrates by a dip-coating approach. The effects of the peptizing agents on the properties of the sols and the membranes were investigated. γ-alumina nanofiltration membranes with an average membrane thickness of 1.8 μm were obtained after sintered at 600 °C for 2 h. The molecular weight cut-off of the γ-alumina nanofiltration membranes, as obtained by filtration of an aqueous PEG solution, was approximately 1 kDa. This membrane also showed a typical retention for monovalent ions and divalent ions. Additionally, the nanofiltration membranes exhibited a relatively high pure-water flux (>20 L/(m 2 h bar)), which is four times higher than that of the γ-alumina nanofiltration membranes reported in the literature. The contribution ratios of different microstructure factors on pure-water flux were calculated. The change in tortuosity with a contribution ratio of 75.6% was the main factor for the improvement of pure-water flux.
研究领域:
材料科学
·
环境工程
✓ 已验证
DOI
高影响因子
JOURNAL OF THE CERAMIC SOCIETY OF JAPAN
·
2022
·Vol. 130
·期 5
·341-350
·
IF 1.217
Lu Li,Hongbing Yang,Libin Zhao,Yuanyuan Li,Bing Shen,Masood Mukhtar,Jiangong Li
High-yield production of high-purity, disperse, ultrafine, and equiaxed gamma-alumina (γ-Al2O3) nanoparticles with narrow size distributions are essential for their applications. However, the synthesis of γ-Al2O3 nanoparticles by calcination of alumina precursors usually results in severe aggregates. In our present work, commercial γ-Al2O3 particles with an irregular shape, large size, and severe aggregates were directly ball-milled. The milled powders were subsequently corroded with hydrochloric acid to obtain γ-Al2O3 nanoparticles. The γ-Al2O3 nanoparticles obtained are dispersed without aggregates, equiaxed in shape, and ultrafine with a mean particle size of 6.2 nm. The disperse γ-Al2O3 nanoparticles are with high purity (99.994 %, mass per cent) and yield. Then γ-Al2O3 nanoparticles were separated by fractionated coagulation to narrow their size distribution. After coagulation separations, γ-Al2O3 nanoparticles with mean particle sizes of 4.8, 6.6, and 7.7 nm and respective size distributions of 2–9, 2–12, and 2–15 nm were acquired. This high-yield preparation process for γ-Al2O3 nanoparticles is simple and scaled up. Furthermore, using commercial γ-Al2O3 powders as starting material, disperse, and equiaxed α-Al2O3 nanoparticles with a mean particle size of 7.6 nm and purity of 95.98 % (mass per cent) were also prepared by ball milling at a higher ball-to-powder weight ratio of 60:1 and acid corrosion.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2016
·
IF 3.349
Jing Xu,Abdul-Rauf Ibrahim,Xiaohui Hu,Yanzhen Hong,Yuzhong Su,Hongtao Wang,Jun Li
Alumina was synthesized from Al(NO 3 ) 3 , AlCl 3 and Al 3 (SO 4 ) 2 with NaOH, and from NaAlO 2 with HNO 3 by addition of acidic solution to alkaline solution with a syringe pump. The as-produced Al 2 O 3 precursors were supercritically dried and calcined at 500 °C to obtain mesoporous γ-alumina material. Results showed that all the inorganic aluminum salts could be used to synthesize high pore volume γ-alumina by controlling the precursor addition rate at room temperature and supercritical CO 2 drying. However, the γ-alumina with the largest pore volume (5.4 cm 3 /g), BET surface area (423.7 m 2 /g) and pore size (37.8 nm) was obtained using Al(NO 3 ) 3 and NaOH. This γ-alumina was further used as a support for Fe-based catalyst with hydrogen peroxide to produce hydroquinone and catechol in the phenol hydroxylation reaction in 30 min at 80 °C. The conversion of phenol was 53.4% whereas the selectivity to dihydroxybenzenes-DHBs (hydroquinone-HQ and catechol-CAT) was as high as 96.2%, revealing that the larger pore volume takes effect in the γ-alumina as support for the Fe-based catalyst in the hydroxylation reaction, and that the γ-alumina may be a good candidate as the support for other important catalysts such as those used in the petroleum refining industry.
研究领域:
化学工程
·
催化材料
✓ 已验证
DOI
高影响因子
International Journal of Applied Ceramic Technology
·
2018
·Vol. 15
·期 6
·1490-1501
·
IF 1.165
Xiangli Kong,Minghui Qiu,Anran Wang,Lu Yang,Rongfei Zhou,Yiqun Fan,Deshuang Kong,Changjun Gu
The adhesion and cohesion between the coating layers and the ceramic honeycombs are usually one of the key issues in the preparation of high-performance zeolite-based/Monolith catalysts. In this work, we investigate the deposition of high-efficiency Cu-SAPO-34 catalyst on a cordierite monolith with special focus on the impact of alumina binders on the structure, mechanical adhesion and cohesion, and catalytic performance of the monolithic catalyst. Two kinds of alumina nanoparticles, α-alumina and γ-alumina, have no significant impacts on the Cu-SAPO-34 crystal structure, micropore morphology and catalytic activity. But washcoating experiments showed that the mass loss rate of the coating was less and the loading of the catalyst was higher when α-alumina was used as the binder. The reason of improving the adhesion and cohesion strength is the suitable thermal shrinkage, the uniform distribution and densification structure of α-alumina. Furthermore, optimization of the coating formulation with α-alumina as the binder has been performed. Finally, the catalyst prepared under the optimal conditions was tested by SCR and a maximum conversion rate of 97.4% was obtained. It was concluded that the use of the washcoating method with α-alumina does not affect catalytic performance while it increases bonding strength between substrate and catalysts.
研究领域:
化学工程
·
催化材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF CATALYSIS
·
2023
·
IF 7.3
Yujie Wan,Pengfei Ma,Hongliang Lu,Jianping Zhang,Jie Wang,Weiping Fang,Wenjing Song,Quanxing Zheng,Weikun Lai
Hydrogen spillover had played a significant role in catalytic processes involving reducible oxide supported metal catalyst and hydrogen molecule. Herein, crystal plane regulative hydrogen spillover strategy for the effective reductive amination on Ni/Al 2 O 3 was developed. A rod-like alumina supported Ni catalyst with primarily external (1 1 1) facets was prepared. In the presence of NH 3 and H 2 , Ni/Al 2 O 3 (1 1 1) exhibited a turnover number of 30.4 h −1 , which was 136-fold higher than that of Ni/Al 2 O 3 (1 1 0) in the reductive amination of furfural to furfuryl amine. For the Ni/Al 2 O 3 (1 1 1) catalyst, Al 2 O 3 (1 1 1) facets exhibited strong Lewis acidity, resulting in an enhanced H affinity of Al 2 O 3 (1 1 1) and a positively charged of Ni through electronic interaction. It was revealed that strong H affinity of Al 2 O 3 (1 1 1) and positively charged Ni sites significantly promoted hydrogen migration from Ni surface to Al 2 O 3 (1 1 1) facets, which effectively prevented the Ni sites from hydrogen poisoning and enhanced the adsorption and activation of NH 3 and intermediates for reductive amination. Consequently, the activation energy of Schiff base reductive ammonolysis was obviously reduced, resulting in high inherent activity for furfural reductive amination to furfuryl amine. This work developed a new strategy for high efficiency reductive amination catalyst in terms of hydrogen spillover effect.
研究领域:
催化化学
·
材料科学
·
能源化学
✓ 已验证
产品关联
DOI
高影响因子
LANGMUIR
·
2018
·
IF 3.789
Ya-Ping Wang,Peng Zhou,Shi-Zhong Luo,Xue-Pin Liao,Bin Wang,Qian Shao,Xingkui Guo,Zhanhu Guo
Polymer/inorganic nanocomposites exhibit special properties due to highly intimate interactions between organic and inorganic phases and thus have been deployed for various applications. Among them, nanocomposites with monolayer polymer coverage on the inorganic surface demonstrate the highest efficiency for applications. However, the controllable synthesis of the polymer monolayer in mesopores of inorganic substrates remains a challenge. In this study, poly(acrylic acid)/γ-alumina nanocomposites (PAA/alumina) were synthesized via the in situ polymerization of acrylic acid impregnated in mesopores of alumina. By applying the preneutralization of monomers, the polymerization was found to be highly controllable in generating monolayer PAA coverage. The formation of monolayers was verified by thermogravimetry, semiquantitative Fourier transform infrared spectroscopy, N2 adsorption–desorption, and Pb(II) adsorption. Alternatively, the organic loadings of PAA/alumina composite samples could be controlled in the range of 0.2 to 1.0 equiv of monolayer, together with the linearly correlated metal ion adsorption capacity. As calculated by the complexation model, one Pb(II) is combined with two carboxylate groups of PAA. The formation of the monolayer polymer inside mesoporous oxide channels represents a method for the development of highly promising functional nanocomposites.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
PubMed
高影响因子
Catalysis Science & Technology
·
2023
·Vol. 13
·期 14
·4156-4167
·
IF 5
Ji Feng,Lin Liu,Xiaohua Ju,Qike Jiang,Jiemin Wang,Jianping Guo,Teng He,Ping Chen
Utilization of promoters to improve the catalytic performance of supported metal catalysts is an important strategy for the design of efficient catalysts. However, it is difficult to detect the relationship between the promoters and the structure of main catalysts. Herein, we firstly develop an efficient Ru-based ammonia synthesis catalyst by decorating Ru nanoparticles (NPs) on γ-alumina with sub-nanometer ceria (CeO2) species (Ce–Ru/Al2O3). In comparison with neat Ru/Al2O3, Ce–Ru/Al2O3 exhibits up to 10-fold activity enhancement at 400 °C and 1.0 MPa. Our characterization results show that such an activity increment is relevant to the function of the sub-nanometer CeO2 species on the Ru NPs. The sub-nanometer CeO2 species will aggregate around the Ru nanoparticles, leading to a clear electron transfer from sub-nanometer CeO2 species to Ru nanoparticles. At the same time, the introduction of CeO2 species can not only weaken the hydrogen poisoning effect on the Ru nanoparticles but also facilitate nitrogen adsorption and hydrogenation of dissociated N* atoms according to the kinetic test results. This work highlights the important role of highly dispersed rare earth oxide promoter species in modulating the structure and catalytic performance of supported Ru NPs for ammonia synthesis.
研究领域:
催化化学
·
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）