Catalysts
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2021
·Vol. 11
·期 12
·1464
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IF 4.146
Su Yang,Xiaoxuan Guo,Xiaomei Pan,Liuyu Gu,Xueping Liu,Lijing Gao,Guomin Xiao
Concentrated sulfuric acid is generally used as a catalyst for producing brominated alkanes in traditional methods, but is highly corrosive and difficult to separate. This work reports the preparation of bromopropane from n-propanol based on a reactive distillation strategy combined with alumina-modified sulfated zirconia (Al2O3/SO42−/ZrO2) as a heterogenous catalyst. As expected, under the optimum reaction conditions (110 °C), the yield of bromopropane was 96.18% without side reactions due to the reactive distillation strategy. Meanwhile, the microscopic morphology and performance of Al2O3/SO42−/ZrO2were evaluated by X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), Brunner–Emmet–Teller (BET), Fourier transform infrared spectroscopy (FT–IR), and other characterization methods. The results confirmed that the morphology of zirconia sulfate is effectively regulated by the modification method of alumina, and more edges and angles provide more catalytic acid sites for the reaction. Furthermore, Al2O3/SO42−/ZrO2exhibited high stability and remarkable reusability due to the strong chemical bond Zr–Al–Zr. This work provides a practical method for the preparation of bromopropane and can be further extended to the preparation of other bromoalkanes.Keywords:sulfated zirconia;modification of alumina;bromopropane;catalytic distillation
研究领域:
化学工程
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催化
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有机化学
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产品关联
DOI
高影响因子
MINERALS ENGINEERING
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2025
·
IF 5
Lijia Zhu,Yimin Zhu,Wenliang Xiong,Zheng Zhou,Peng Gao,Yuexin Han
Metal ions, naturally present in flotation pulp, are commonly employed in flotation reagents, serving as vital reagents in mineral separation processes. This study investigated the impact of ASS, a blend of AlCl 3 , sulfuric acid, and sodium silicate (SS), on the flotation separation efficiency of fluorite from dolomite, as well as the underlying interaction mechanism. Micro flotation tests revealed that ASS significantly decreased the flotation recovery of dolomite while exerting negligible influence on that of fluorite. The difference in flotation recovery rates among the two minerals reached 92.00 % with the addition of 103 mg/L of ASS. The artificial mixed mineral flotation tests were also carried out, the recovery rate and grade of F in the concentrate were 86.47 % and 42.79 %, respectively. The formation of the metal complex ASS, resulting from the combination of Al with Si(OH) 4 , facilitated the adsorption of their hydrolysis products on the surface of dolomite. Within the flotation pulp system, the Ca 2+ and Mg 2+ on the dolomite surface selectively interact with the –OH groups in ASS. At the same time, the Al 3+ in ASS selectively bonds with the O atom of the carbonate group exposed on the dolomite surface. This interaction promotes the adsorption of ASS onto the dolomite surface, thereby hindering the adsorption of sodium oleate. The fluorite surface exhibited weaker interactions with ASS, leading to more sodium oleate adsorbed on the surface of fluorite, thereby increasing the hydrophobicity of the fluorite particles, which floated up. As a result, the selective adsorption of the reagents facilitated the flotation separation of fluorite from dolomite.
研究领域:
矿物加工工程
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材料化学
✓ 已验证
产品关联
DOI
高影响因子
Frontiers of Chemical Science and Engineering
·
2023
·Vol. 17
·期 11
·1776-1787
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IF 4.5
Zhang Jing-Xuan,Wang Xuan,Feng Yan-Ru,An Jia-Yu,Chi Yu-Xuan,Liu Ya-Tai,Zhang Ling-Fei,Zhao Yun-Bo,Zeng Xiang-Feng,Wang Zi-Bo,Liu Jia-Shuai,Wang Yi-Fan,Dou Shuai-Yong,Duan Er-Hong,Meng Tao
Compared with traditional hydrodesulfurization, new nonhydrodesulfurization methods have the advantage of a high removal efficiency for thiophene compounds under mild conditions. However, independent nonhydrodesulfurization technologies are faced with their own shortcomings, such as limitations of the desulfurization performance and regeneration of materials. To overcome these limitations, four nanofluids were prepared by dispersing different metal-modified MCM-41 particles in deep eutectic solvent as multifunctional promoters to develop a comprehensive desulfurization method. Based on the excellent adsorbability and high catalytic activity of the dispersed particles and the outstanding extractability of deep eutectic solvent in nanofluids, a high sulfur removal of 99.33% was achieved for model oil under mild conditions in 15 min. The nanofluids also showed excellent reusability due to their high structural stability. In addition, NF@Cu/Al-MCM-41-2.5% exhibited the best desulfurization performance among the prepared nanofluids. This result was obtained because the introduction of Al ions increased the number of acid sites and defect sites to improve the catalytic activity and adsorbability, and the best affinity of Cu/Al-MCM-41 for the deep eutectic solvent favored the reaction mass transfer. This work opens the door to the development of a comprehensive nonhydrodesulfurization method based on the design of nanofluid materials.
研究领域:
化学工程
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材料科学
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环境科学
✓ 已验证
DOI
高影响因子
ENVIRONMENTAL POLLUTION
·
2024
·
IF 7.6
Xiuyan Wang,Tianxiao Li,Xin Hu,Yuxuan Zhang,Dunhan Zhang,Hanshuo Zhang,Hongxia Xu,Yuanyuan Sun,Xueyuan Gu,Jun Luo,Bin Gao
Although selenium is an essential nutrient, its contamination in water poses serious risks to human health and ecosystems. In this study, aluminum-modified bamboo biochar (Al-BC) was developed to reclaim Se(VI) from water. Compared to pristine biochar (BC), Al-BC had a larger specific surface area (176 m 2 /g) and pore volume (0.180 cm³/g). The modification, achieved by loading AlOOH and Al 2 O 3 particles onto the surface, enabled Al-BC to achieve a maximum adsorption capacity of 37.6 mg/g for Se(VI) within 2 h and remove 99.6% of Se(VI) across a pH range of 3–10. The main adsorption mechanism of Se(VI) involved electrostatic attraction, forming outer-sphere complexes between Se(VI) and AlOOH sites on the biochar. The bioavailability of Se sorbed on the spent biochar (Al-BC-Se) was thus evaluated. It was discovered that Al-BC-Se successfully released Se(VI), which impacted the growth of wheat seedlings. The Se content reached 134 μg/g dry weight (DW) in wheat shoots and 638 μg/g DW in roots, significantly exceeding normal selenium content (<40 μg/g DW). By successfully applying the modified biochar to capture selenium from water through adsorption and then reusing it as an essential nutrient in soil, this study suggests the promising feasibility of the "removal-collection-reuse" approach for the circular economy of selenium in wastewater.
研究领域:
环境科学
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农业科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2022
·
IF 16.744
Haifeng Yang,Chuanhao Xu,Weimiao Wang,Pengfei Tang,Xiaodong Li,Shanshan He,Hebin Bao,Shuaishuai Man,Deyun Tang,Xueming Li,Guangcheng Yang,Zhiqiang Qiao
Micro-propulsion underwater technology has been an extensively concerned topic in advanced marine energy systems because of its wide prospects in high-precision prospecting and positioning. Wherein, the design and selection of propellant in energy-supply systems are the key issues to greatly explore its future application. Here, the hydrophobic thermite sticks which contain hydrophobic polytetrafluoroethylene nanoparticles and modified aluminum coated with 1H, 1H, 2H, 2H-perfluorodecyltriethoxysilane shells, were fabricated via a simple direct-writing approach. The modified thermite sticks exhibit stable underwater combustion and self-sustained propagation with a small diameter size (0.94 ± 0.05 mm). In-situ observation shows that the underwater reaction process could be divided into three steps: laser-induction, organic decomposition-dissolution, and thermite reaction. The aging results indicate that the thermite sticks demonstrate an excellent storage stability wherever in air or underwater environments. Simultaneously, it is found that its critical energy required to sustain stable underwater combustion is higher than that in air. Most notably, it not only can be used as the fuels for controllable miniature underwater propulsion, but also can be applied as the energy-delivery materials to expand thrust capacity of vehicles by igniting higher impulse explosives, such as CL-20.
研究领域:
材料科学
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海洋工程
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能源技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CATALYSIS
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2021
·
IF 7.92
Yue Ma,Songqi Cheng,Xiaodong Wu,Tongxi Ma,Liping Liu,Baofang Jin,Minghan Liu,Jianbo Liu,Rui Ran,Zhichun Si,Duan Weng
To improve the hydrothermal durability of Cu-SSZ-13 selective catalytic reduction (SCR) catalyst, a thin Al 2 O 3 modification layer was coated on the external surface of Cu-SSZ-13 by a chemical liquid deposition (CLD) method. The high-temperature SCR activity of the Al-modified Cu-SSZ-13 can be maintained upon 750–800 °C hydrothermal aging, and over-oxidation of NH 3 is largely inhibited. Based on H 2 -TPR and EPR results, it is revealed that CuAl 2 O 4 -like species forms upon Al modification and converts further to CuAlO 2 -like species during aging, while the accumulation of CuO-like species is inhibited. The high affinity of Al-containing species ( i.e. , Al 2 O 3 and CuAl 2 O 4 -like species) with Cu(OH) 2 is suggested by DFT calculations, indicating that Cu(OH) 2 detached from ion-exchange sites are captured by Al to form CuAlO 2 -like species instead of CuO-like species. The passivation of detached Cu species by coated Al leads to somewhat weakened low-temperature SCR activity, but successfully preserves the high-temperature SCR performance upon aging, which can be applied to high-temperature SCR scenarios.
研究领域:
催化化学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL GEOCHEMISTRY AND HEALTH
·
2024
·Vol. 47
·期 1
·1-18
·
IF 3.2
Gong Huichun,Ke Pingchao,Zhou Yipeng,Xu Lingling,He Guang,Jian Peng
Fluoride contamination is a serious environmental problem in lepidolite hydrometallurgy wastewater. The treatment of fluoride-bearing wastewater is challenging because of the presence of coexisting ions including lithium (Li + ), rubidium (Rb + ), silicate (SiO 3 2− ), sulfate radical (SO 4 2− ). However, aluminum-modified zeolite (Al@zeolite) with sufficient hydroxyl groups and high adaptability has unique advantages for eliminating fluoride from lepidolite hydrometallurgy wastewater. Al@zeolite was prepared on natural zeolite by an atmospheric process and then used for the adsorption of fluorine from fluoride-bearing wastewater produced by the lepidolite hydrometallurgy process. The results of material characterization confirmed the successful immobilization of aluminum within the zeolite pores and indicated the formation of zeolite-Al–OH. The zeolite host significantly enhanced the chemical stability of Al@zeolite against pH changes for a wide pH range of 2.0–10.0. The adsorbent had a surface area of 33.46 m 2 /g and demonstrated excellent capacity and selectivity for fluoride adsorption. Notably, a maximum adsorption of 98.6% was observed at a pH value of 6.0 for a duration of 20 min with a fluoride content of 20 mg/L, and the equilibrium concentration decreased to 0.4 mg/L. The results of fluorine adsorption showed that fluoride uptake onto Al@zeolite agreed well with the pseudo-second-order kinetic model and the Langmuir isotherm model. The reusability of the substance was evaluated for up to eight cycles following consecutive regeneration with 0.2 mol/L AlCl 3 . The exhausted Al@zeolite was effectively regenerated through simple alkaline treatment for recycling. The above results verified that Al@zeolite is a new kind of efficient defluoridation adsorbent for lepidolite hydrometallurgy wastewater with practical application prospects.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
DESALINATION
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2025
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IF 9.8
Xin Li,Xifan Li,Quanxun Liang,Guijing Chen,Wenjie Wang,Jin Bao,Jiawang Qin,Shun Tang,Xiao Lin,Alberto Tiraferri,Baicang Liu
The growing demand for lithium in energy storage batteries has driven interest in extracting lithium from shale gas wastewater as a sustainable alternative to traditional mining. To address challenges such as high cycling loss of adsorbent powder and complex operational procedures, this study developed adsorbent spheres by pelletizing Al-modified H 1.33 Mn 1.67 O 4 powder with polyvinyl chloride (PVC) as the skeleton material, and introducing cellulose acetate (CA) or Pluronic F127 as hydrophilic modifiers. CA-modified powder exhibited superior mechanical stability, internal porosity, and hydrophilicity. These properties reduced interference from organic matter and allowed a lithium adsorption capacity of 20.2 mg/g, surpassing the 18.8 mg/g capacity of unmodified PVC particles. Adsorption behavior followed the Freundlich isotherm model, while pseudo-second-order kinetics indicated that multi-step and multi-layer chemisorption governed lithium uptake. In fixed-bed filtration experiments, the optimal empty bed contact time (EBCT) was determined to be 40 min, leading to an adsorption saturation bed volume more than 40 times the empty bed volume. Desorption enrichment provided lithium concentrations of approximately 200 mg/L. The adsorbent maintained its adsorption capacity over 10 adsorption-desorption cycles, with manganese dissolution losses below 0.3 % and in some cases as low as 0.2 %. These findings confirm the durability and efficacy of the novel composite adsorbent in lithium recovery, offering a significant step toward more efficient and sustainable lithium extraction from treated shale gas wastewater.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
Water Supply
·
2024
·Vol. 24
·期 6
·2172-2184
·
IF 1.9
Ren Mengyue,Jia Xiangling,Huang Tianyin,Wu Bingdang,Yang Jingjing
View large Download slide View large Download slide Close modal Efficient and low-cost removal of fluoride from water has attracted wide attention. Here, aluminum-modified hydroxyapatite (Al-HAP) was prepared by a homogeneous hydrothermal co-precipitation method. The physicochemical properties of the Al-HAP surface were characterized by SEM, XRD, FT-IR, BET, and zeta potential, and the adsorption performances were evaluated. It showed that Al-HAP has a larger specific surface area (121.97 m 2 /g, which is 2.3 times larger than that of HAP), more surface-active hydroxyls and positively charged at pH less than 7, which indicate that Al-HAP is beneficial to the adsorption of negatively charged fluoride. Al-HAP had a higher fluoride adsorption capacity (56.44 mg/g) than that of HAP (28.36 mg/g), and not sensitive to the interference of coexisting ions except CO 3 2- . Based on the adsorption kinetics and adsorption isotherm experiments, the proposed two-stage kinetic model and Freundlich isotherm model can better describe the adsorption process. From the results of XPS and FT-IR, it indicated that the ion exchange between hydroxyl group on the surface and fluoride ions is the main driven force for the adsorption, and electrostatic adsorption is also helpful. The present study provides an improved HAP to effectively remove fluoride from water. Aluminum-modified hydroxyapatite (Al-HAP) was prepared by a co-precipitation method. The adsorption efficiency of Al-HAP was 30% higher than that of HAP. Al-HAP belongs to mesoporous structure with larger specific surface area. The equilibrium adsorption capacity of Al-HAP is 56.44 mg/g at 298 K. The main mechanism is ion exchange.
研究领域:
环境科学
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材料科学
✓ 已验证
DOI
高影响因子
Journal of Environmental Sciences
·
2021
·
IF 5.565
Xueyi Dong,Xihua Cao,Wenbin Jiang,Xiuxian Song,Zhiming Yu,Shitao Yu
Polyaluminum chloride modified clay (PAC-MC) is a safe and efficient red tide control agent that has been studied and applied worldwide. Although it is well known that the distribution of hydrolytic aluminum species in PAC affects its flocculation , little is known about the influence of particulars aluminum species on the microalgae removal efficiency of PAC-MC; this lack of knowledge creates a bottleneck in the development of more efficient MCs based on aluminum salts. The ferron method was used in this study to quantitatively analyze the distributions of and variations in different hydrolytic aluminum species during the process of microalgae removal by PAC-MC. The results showed that Al a , which made up 5%–20% of the total aluminum, and Al p , which made up 15%–55% of the total aluminum, significantly affected microalgae removal, with Pearson's correlation coefficients of 0.83 and 0.89, respectively. Most of the aluminum in the PAC-MC sank rapidly into the sediments, but the rate and velocity of settlement were affected by the dose of modified clay. The optimal dose of PAC-MC for precipitating microalgae was determined based on its aluminum profile. These results provide guidance for the precise application of PAC-MC in the control of harmful algal blooms .
研究领域:
环境科学
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水处理工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Environmental Chemical Engineering
·
2023
·
IF 7.7
E. Shuang,Qiong Wang,Kuichuan Sheng,Ximing Zhang
The development of a simple and feasible process for preparing adsorbent materials to recover phosphorus resources would have significant environmental and social benefits. In this study, the Al-modified hydrochar was synthesized for phosphate adsorption by hydrothermal carbonization in one pot using corn stover as raw material. The results showed that phosphate adsorption mainly depended on the precipitation reaction between Al element and phosphate, in which the hydrochar carrier played a synergistic role. Al element through the hydrothermal treatment loaded on hydrochar expressed a much higher phosphate adsorption performance than that on pyrochar. When the concentration of AlCl 3 solution added in the hydrothermal process was 2 mol·L −1 and the hydrothermal temperature exceeded 180 ℃, Al element could transform from the amorphous state, which was less effective for phosphate adsorption, to Al 24 O 11 (OH) 44 Cl 6 crystal with high adsorption performance and could be more stably loaded onto the hydrochar. Although the preparation process was simple, the adsorption performance of hydrochar is good. The phosphate adsorption capacity and removal efficiency by the hydrochar prepared at 260 °C reached to 114.40 mg·g −1 and 76.27%, which could be further increased by adjusting the dosage of adsorbent and pH of water. The pseudo-second-order kinetic model and Langmuir isotherm model could better describe the phosphate adsorption process on Al-loaded hydrochar. Phosphate was rapidly adsorbed on the surface of the hydrochar rich in mesoporous structure and bound to the surface-active sites. This study could transform agricultural waste into a functional hydrochar-based adsorbent and provide a low-cost, simple operation and efficient phosphate removal technology .
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2023
·Vol. 47
·期 16
·7810-7818
·
IF 3.3
Yanke Guo,Qiaoyun Qin,Jing Zhu,Baohe Wang
Propylene glycol methyl ether was directly synthesized from propylene and hydrogen peroxide under mild conditions via aluminum modified titanium silicalite-1 as a bifunctional catalyst. It has both active sites capable of epoxidation and active sites capable of ring opening reactions, thus realizing the one-pot preparation of propylene glycol methyl ether by propylene. The synergistic effect of Ti–Al on the catalytic performance and the distribution of propylene glycol methyl ether isomer were investigated in detail, and the synergistic catalysis between the two active sites was characterized. The gradual introduction of aluminum reduced the activation ability for hydrogen peroxide, but gradually increased the selectivity for propylene glycol methyl ether. Under the optimum conditions, the selectivity for propylene glycol methyl ether reached 91.53%. Combined with Density Functional Theory (DFT) calculations, the synergistic catalytic effect of doped Al and framework Ti in titanium silicalite-1 is discussed in detail from a microscopic perspective. Al increases the Lewis acid strength of Ti active sites and promotes the conversion of propylene to propylene oxide (PO), and simultaneously Ti increases the Brønsted acid strength of Al active sites and promotes the conversion of propylene oxide to propylene glycol ether.
研究领域:
化学工程
·
催化科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）