SEPARATION AND PURIFICATION TECHNOLOGY
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2024
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IF 8.1
Lin-Jiang Zhong,Shu-Jie Hu,Di Wu,Meng-Yue Zhang,Hong Liu,Yuan Liu
Both the sustainable development and environmental protection urge a demand of new paradigm to recover high-quality nutrients from source-separated urine, but the simultaneous recovery of phosphorus and nitrogen is difficult due to the complex composition. Herein, a coupled system consisting of a flow-electrode capacitive desalination and magnesium-air fuel cell (FCDI-MAFC) was proposed to accomplish electrochemical selective separation plus induced precipitation. The results showed that ionic species in urine were effectively separated from the non-ionic components to generate a urea solution with purity up to 99.7%. Ionic species were converted into artificial phosphate ores (APOs) with a phosphate content of 98.2%. The mass proportion of struvite in the APOs exceeded 90%. The energy consumption also decreased by 13% over five batches of operation. The overall results provide a novel method for the electrochemical selective separation and recovery of high-quality nutrients from complex wastewater.
研究领域:
环境科学
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资源回收
·
电化学工程
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DOI
高影响因子
HYDROMETALLURGY
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2022
·
IF 4.217
Zhihe Cao,Baozhong Ma,Chengyan Wang,Bingding Shi,Yongqiang Chen
Currently, with the increasing demand of nickel and cobalt, more and more attention has been placed on hydrometallurgical processing to treat laterite ore. The nitric acid pressure leaching (NAPL) has several advantages. In order to solve the problems of environmental pollution and resource wastage caused by the NAPL residue, this work proposes a novel and green process for treating laterite residue to prepare high-purity iron phosphate. The laterite residue was subjected to selective leaching by 6.0 mol L −1 phosphoric acid . The pregnant leach solution (PLS) was used to prepare iron phosphate by induced precipitation. The selective leaching was conducted using 6.0 mol L −1 H 3 PO 4 of to obtain high extraction of iron. After leaching and clarification of PLS iron phosphate was precipitated in two steps by controlling temperature and pH, to yield more than 94% iron phosphate. The reaction mechanism of the induced precipitation was analyzed, which illustrated that intermediate products were first formed from the leach liquor and then transformed to FePO 4(s) . Characterization of the iron phosphate showed that the product displayed flowerlike morphology with high purity and dispersion. This process not only solves the serious environmental damage by accumulation and landfill of laterite residue, but also improve the efficiency of resource utilization for the hydrometallurgical nickel laterite industry.
研究领域:
冶金学
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材料科学
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环境科学
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DOI
高影响因子
ChemCatChem
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2017
·Vol. 10
·期 5
·1166-1172
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IF 4.803
Lan-Lan Lou,Huaxin Qu,Wenjun Yu,Bei Wang,Lezi Ouyang,Shuangxi Liu,Wuzong Zhou
Graphical Thermoresponsive lipase catalyst : A UCST-type thermoresponsive polymer–lipase conjugate was exploited and applied as an asymmetric biocatalyst in the kinetic resolution of racemic α-methylbenzyl butyrate, exhibiting high catalytic performance, easy recovery, and good durability. A thermoresponsive lipase catalyst with an upper critical solution temperature (UCST) of about 26 °C was exploited by covalent immobilization of an enzyme, Pseudomonas cepacia lipase (PSL), onto poly(acrylamide- co -acrylonitrile) by glutaraldehyde coupling. The experimental conditions for the PSL immobilization were optimized. The immobilized PSL was much more stable for wide ranges of temperature and pH than free PSL. The material was also evaluated as an asymmetric catalyst in the kinetic resolution of racemic α-methylbenzyl butyrate at 55 °C in an aqueous medium and exhibited high catalytic performance and stability. Up to 50 % conversion and 99.5 % product enantiomeric excess were achieved, thus providing highly pure enantiomers. This biocatalyst could be easily recovered by simple decantation for reuse based on temperature-induced precipitation. It showed good reusability and retained 80.5 % of its original activity with a well reserved enantioselectivity in the 6th cycle. This work would shed light on the future development of new UCST-type enzyme catalysts.
研究领域:
生物化学
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酶工程
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材料科学
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DOI
高影响因子
BIOSENSORS & BIOELECTRONICS
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2016
·
IF 7.476
Huayu Xiong,Huiling Zheng,Wei Wang,Jichao Liang,Wei Wen,Xiuhua Zhang,Shengfu Wang
Herein, we report a convenient approach to purify water-soluble dihydrolipoic acid (DHLA)-capped Ag nanoclusters (Ag NCs) by pH-induced precipitation under acidic conditions. The fluorescence of Ag NCs could be completely recovered by re-dispersing the precipitate into a basic solution using DHLA and NaBH 4 as stabilizing ligands and etching reagent. DHLA-Ag NCs-doped agarose hydrogels have been prepared to monitor pH with a wide range from 8.0 to 4.0. When pH decreased, the fluorescence of the hydrogels under a UV lamp decreased and completely disappeared after pH 5. The DHLA-Ag NCs-doped agarose hydrogels biosensor showed low cytotoxicity and long stability. Accordingly, a fluorescent pH sensor for bacterial monitoring has been employed based on the “OFF–ON” signal switch of the Ag NCs-agarose hydrogel.
研究领域:
纳米技术
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材料科学
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分析化学
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生物医学工程
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产品关联
DOI
PubMed
高影响因子
ENVIRONMENT INTERNATIONAL
·
2019
·
IF 7.943
Qian Sun,Cun Liu,Peixin Cui,Tingting Fan,Mengqiang Zhu,Marcelo Eduardo Alves,Matthew G. Siebecker,Donald L. Sparks,Tongliang Wu,Wei Li,Dongmei Zhou,Yujun Wang
Apart from surface complexation, precipitation of minerals also plays an important role in reducing the mobility and transport of heavy metals in the environment. In this study, Cd(II) sorption species on surfaces of γ-Al 2 O 3 at pH 7.5 were characterized using multiple techniques. Results show that in addition to adsorption complexes, Cd hydroxide phases (Cd(OH) 2 precipitates and Cd x (OH) y polynuclear complexes) were formed at the initial stages of Cd(II) sorption and gradually transformed to CdCO 3 with time. In addition, Cd(II) formed Cd Al layered double hydroxide (LDH) on γ-Al 2 O 3 under various conditions, independent of temperature and Cd loadings. The formation of Cd hydroxide phases and Cd Al LDH could be ascribed to surface-induced precipitation because the bulk solution was undersaturated with respect to hydroxides. Cd Al LDH formation on the Al-bearing mineral here is rather surprising because typically this occurs with elements of ionic radii similar to that of Al 3+ ; this formation is unknown for metals such as Cd(II) with a much larger ionic radius. The thermodynamic feasibility of Cd Al LDH formation was further confirmed by laboratory synthesis of Cd Al LDH and density function theory (DFT) calculations. These results suggest that Cd precipitation on Al-bearing minerals can be an important mechanism for Cd immobilization in the natural environment. Additionally, the finding of Cd Al LDH formation on Al-bearing minerals and the thermodynamic stability of Cd Al LDH provides new insights into the remediation of Cd-polluted soils and aquatic systems.
研究领域:
环境科学
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地球化学
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材料科学
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产品关联
DOI
PubMed
高影响因子
LANGMUIR
·
2021
·
IF 3.882
Lingqi Zhong,Haizheng Tao,Xiao Gong
In this work, superhydrophobic poly(l-lactic acid) (PLLA) hierarchical membranes exhibiting excellent oil-removal performance, which is of great importance in curbing the oil-pollution environment, were fabricated by a simple solvent-evaporation-induced precipitation method. PLLA membranes with hierarchical micro/nanostructures (fish scales, fibrous sheets, and petal-like morphology) can be conveniently prepared by adjusting the preparation parameters including PLLA concentration, precipitation temperature, type of solvent and nonsolvent, and the addition of nano-SiO2. The results show that the water contact angle of the fish-scale-structured PLLA membrane was 138.6°, revealing that water repellency was significantly improved compared to that of the solvent-casting PLLA membrane (∼72.8°). Moreover, the PLLA/SiO2 nanocomposite membrane with a dense hierarchical micro/nanostructure had a water contact angle greater than 167.1°, which has great potential in oil–water separation.
研究领域:
材料科学
·
环境工程
·
化学工程
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产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）