ACS ES&T Engineering
·
2022
·
IF 0
Jiazhen Cao,Yao Chen,Hengjun Shang,Xiang Chen,Qianyu Qiao,Hexing Li,Zhenfeng Bian
Gold and palladium are the most widely used precious metal materials in the field of electronic devices and industrial catalysis. How to realize the green recycling of gold and palladium is important and challenging. In this work, we found that gold and palladium in wastes, such as electronic devices and industrial catalysts, can be completely dissolved and recycled by photocatalysis. Gold and palladium are oxidized to the ionic state in water, which does not involve strong acids, strong alkalis, toxic cyanides, or an organic medium. More interestingly, the dissolution of gold and palladium in different halogen aqueous solutions has special selectivity, which depends on the coordination stability constants between gold and palladium with halide ions. Therefore, gold and palladium can be selectively dissolved in iodine ion solution and bromine ion solution, respectively, then gold and palladium can be obtained by a one-step reduction. This work opens up a new direction for optimizing the photocatalytic dissolution technology and promoting the green recycling of precious metals.
研究领域:
环境科学
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材料科学
✓ 已验证
DOI
JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY
·
2013
·Vol. 298
·期 3
·1999-2008
·
IF 1.467
Pan Ning,Guan Debin,He Ting,Wang Ruibing,Wyman Ian,Jin Yongdong,Xia Chuanqin
The removal of Th 4+ ions from aqueous solutions was investigated using single-layer graphene oxide (GO) as a sorbent which was prepared by the modified Hummers’ method through batch adsorption experiments at room temperature. Structural characterizations of the sorbent were also investigated. The influences of the pH value of solution, contact time, sorbent dose, ionic strength, the initial metal ion concentration and temperature on the adsorption of Th 4+ were also investigated. These results indicated that the adsorption of Th 4+ was dependent on the pH and independent on the ionic strength. The sorbent provided significant Th 4+ removal (>98.7 %) at pH 3.0 and the adsorption equilibrium was achieved after only 10 min. The Langmuir adsorption isotherm fit the absorption profile very closely, and indicated that a maximum adsorption capacity of 1.77 mmol g −1 of GO (411 mg g −1 ) after 2 h. The thermodynamic parameters showed that this adsorption process was endothermic and spontaneous. Moreover, the desorption level of Th 4+ from GO, by using 0.1 mol L −1 H 2 SO 4 as a stripping agent, was 84.2 ± 1.2 %, and that of 0.5 mol L −1 HNO 3 as a stripping agent, was 79.8 ± 3.0 %.
研究领域:
环境科学
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材料科学
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核化学
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水处理技术
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吸附科学
✓ 已验证
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2016
·
IF 2.567
Lu Jiang,Wei Zhang,Congguang Luo,Daojian Cheng,Jiqin Zhu
Zeolite imidazolate frameworks (ZIFs) have been applied to gas adsorption, but there remain no reports detailing the adsorption–desorption process for lanthanum metal ion (LMI). This work first testifies that ZIF-8 has a better adsorption property than ZIF-90 for remediation of LMI from water. Adsorption results demonstrate that ZIF-8 removes 100.0% of the metals ions, whose concentrations are below 20 mg L–1, and the saturated adsorption capacity is 385 mg g–1. Characterization by P-XRD, ICP, and FT-IR indicates that the main structure of ZIF-8 remained unchanged to a large extent during the adsorption process. Density functional theory (DFT) calculations illustrated that the adsorption process is spontaneous, and the adsorption site is in the center of two imidazole rings. La-ZIF-8 was subjected to two polar desorbents, acetonitrile and methyl alcohol, possessing a desorption ratio of 94.4% and 61.0%, respectively. Recycling the adsorption/desorption process using acetonitrile resulted in significant crystal structure collapse after three recycles reducing the adsorption capacity to 150 mg g–1. However, acetonitrile still maintains a desorption ratio of over 90.0%. Our work shows that ZIF-8 can be used as an efficient adsorbent in the removal of aquatic LMI, especially at trace concentration levels.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2019
·Vol. 55
·期 4
·1854-1864
·
IF 3.442
Zhang Zhizhong,Li Liang,An Duo,Li Hanxue,Zhang Xinghua
Novel triazine-based covalent organic polycalix[4]arenes, CalCOPs, were synthesized via the copolymerization of calix[4]arene derivatives and 2,4,6-trichloro-1,3,5-triazine (TCT) or 2,4-dichloro-1,3,5-triazine (DCT). The resulting CalCOPs have permanent pores that can be regulated by the variation of the alkyl chain lengths of the calixarene backbones and the reaction sites. With the alkyl chain length at the low rim in calixarene units increasing from ethyl to butyl during the reaction, the Brunauer–Emmett–Teller surface areas decrease with surface areas of 280, 31.5, 18.4 and 1.6 m 2 g −1 obtained for CalCOP1, CalCOP2, CalCOP3 and CalCOP4, respectively. Among these CalCOPs, CalCOP1 shows ultrahigh absorption for iodine capture in a water solution with an uptake of up to 232 wt%. Furthermore, the adsorption and release efficiency of iodine were obtained by using the UV–Vis spectroscopy. In addition, these polymers can be recycled at least five times while maintaining high removal capacity, suggesting that CalCOPs are ideal absorbent materials for reversible iodine capture in the mitigation of environmental issues.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of the Taiwan Institute of Chemical Engineers
·
2016
·
IF 2.848
Ruiqi Fu,Yu Liu,Zimo Lou,Zhuoxing Wang,Shams Ali Baig,Xinhua Xu
A novel adsorbent (AC/Fe 3 O 4 @SiO 2 –NH 2 ) was synthesized via a co-condensation process for the enhanced removal of Pb(II) from aqueous solutions. Characterization analyses including SEM, TEM, BET and XRD confirmed the successful integration of magnetic nanoparticles and amino groups with carbon matrix. Results demonstrated that AC/Fe 3 O 4 @SiO 2 –NH 2 (mass ratio of AC to Fe 3 O 4 was 1:0.25) with specific surface area (48.9 m 2 /g) showed higher adsorption capacity for Pb(II) as compared to other mass ratios. Kinetics study revealed that the adsorption reach equilibrium within 20 h and the maximum adsorption capacity of 104.2 mg/g was achieved with increasing the initial concentration from 20 to 250 mg/L using AC/Fe 3 O 4 @SiO 2 –NH 2 . Maximum removal efficiency was recorded at pH 5.2 and the removal capacities toward four divalent metal ions calculated by the Langmuir model were found to be in the order of Pb(II) > Cu(II) > Ni(II) > Cd(II). Furthermore, Δ G 0 decreased from –1.6 to −3.1 kJ/mol with increase in temperature from 293 to 333 K illustrating that the adsorption was spontaneous and an endothermic process. Complexation adsorption mechanism was found prominent in FTIR and XPS analyses between Pb(II) and AC/Fe 3 O 4 @SiO 2 –NH 2 due to the presence of amino groups.
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
JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY
·
2020
·Vol. 326
·期 1
·185-192
·
IF 1.137
Hu Ke,Liu Zhirong,Xiu Taoyuan,Zhou Limin,Wang Yun
The Cu 3 (BTC) 2 (BTC = 1,3,5-benzenetricarboxylic acid) was synthesized by water/solvent heat method. The Cu 3 (BTC) 2 was characterized by SEM/EDS, Zeta potential and XRD. Batch static adsorption experiments investigated the various factors affecting the adsorption of Th(IV) in aqueous solution such as pH, solid–liquid ratio, contact time, initial concentration and temperature, and the adsorption mechanism is also discussed. The adsorption process was in line with the pseudo-second-order kinetic model and the Langmuir isotherm model. At the same time, compared with other adsorbents. The results showed that Cu 3 (BTC) 2 had good adsorption for Th(IV) with a maximum adsorption of 757.58 mg g −1 .
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
ACS Omega
·
2022
·
IF 4.132
Yaohui Sun,Yanhui Li,Bing Chen,Mingzhen Wang,Yang Zhang,Kewei Chen,Qiuju Du,Yuqi Wang,Xinxin Pi
It can be difficult to remove dark methylene blue (MB) from water effectively. The use of sodium alginate and bentonite (Ben) as the matrix produced a displacement reaction that occurred in cobalt chloride, which allowed Ben to be successfully encapsulated in cobalt alginate (CA). Finally, a vacuum freeze-drying method was used to prepare a low-cost composite of CA/Ben aerogel for adsorbing MB in aqueous solutions. In addition to scanning electron microscopy, thermogravimetric analysis, and Fourier transform infrared spectroscopy, the composites were also characterized and analyzed. Different adsorption experiments were conducted in order to determine the effects of dosage, pH, adsorption time, and temperature on the adsorption performance of the adsorbent. According to the results of the experiment, the adsorption capacity of CA/Ben aerogel was 258.92 mg·g–1, and the pseudo-first-order kinetic model and Freundlich isotherm model can fully explain the adsorption process of MB on this aerogel. The composite material reported in this paper is easily recycled, and the removal rate reaches 65% after four times of recycling. Moreover, compared with other adsorbents, the composite material of the invention is highly environmentally friendly and has a simple preparation process. A large-scale application of this technology is the removal of dyes from water on a large scale.
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
SEPARATION AND PURIFICATION TECHNOLOGY
·
2022
·
IF 9.136
Youcai Hu,Jianhua Ding,Guangyuan Ren,Tianxiang Jin,Zhirong Liu,Yong Qian
Efficient separation and enrichment of thorium from aqueous solutions is an important subject in the field of energy and ecological environment. In this study, a novel polymer-based xerogel was prepared by a crosslinking reaction of 2-carboxyethyl phosphonic acid functionalized chitosan(CCS-TCEP) and was applied to the adsorption of Th(IV) ions. The maximum adsorption capacity of CCS-TCEP could reach 311.6 mg/g with an excellent selectivity due to the abundant binding sites for thorium provided by TCEP. Moreover, this material has a high adsorption rate and the adsorption equilibrium could be reached within 60 min. After 5 cycles of reuse, the adsorption capacity of CCS-TCEP still retained more than 80 % of its initial value. Furthermore, the extraction mechanism of CCS-TCEP for Th(IV) ions was also analyzed in detail by FT-IR, XPS and DFT calculation. This study indicates that CCS-TCEP can be used as a potential adsorbent for efficient extraction of thorium from aqueous waste.
研究领域:
能源与环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
FOOD CHEMISTRY
·
2021
·
IF 7.514
Umarbek Alimov,Kaiyu Zhao,Jiayin Hu,Yafei Guo,Lingzong Meng,Xiuyun Pan,Tianlong Deng
The purpose of this exploration was to determine the density and volumetric properties of the aqueous solution of Na 2 H 2 P 2 O 7 with the molality varied from 0.08706 to 0.88402 mol·kg −1 measured at temperature intervals of 5 K from 283.15 to 363.15 K at 101.325 kPa using Anton Paar Digital vibrating-tube densimeter. The thermal expansion coefficient ( α ), apparent molar volume ( V Φ ), expansibility ( ϕ E ), and partial molar volume ( V B ) of Na 2 H 2 P 2 O 7 (aq) against temperature and molality have been evaluated from density data. On the basis of Pitzer ion-interaction apparent molar volume theory, the Pitzer single-salt parameters ( β M , X 0 v , β M , X 1 v , β M , X 2 v and C M , X v , MX = Na 2 H 2 P 2 O 7 ), and their correlation coefficients a i of the temperature-dependence formula f ( i , p , T ) = a 1 + a 2 ln( T /298.15) + a 3 ( T − 298.15) + a 4 /(620 – T ) + a 5 /( T − 227) for Na 2 H 2 P 2 O 7 were obtained for the first time. It was revealed that predicted apparent molar volumes agreed well with the experimental values indicating the single salt parameters and the temperature-dependent formula are reliable.
研究领域:
物理化学
·
无机化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF SOLUTION CHEMISTRY
·
2023
·Vol. 52
·期 12
·1331-1351
·
IF 1.2
Chen Zhirong,Yao Yang,Yuan Shenfeng,Yin Hong
Critical temperature, critical pressure and P–T–ρ–X data of acetone–water solutions with water mole fractions in a range of 0–60% were measured to provide fundamental data for CFD simulations. Critical temperatures were determined via observing critical opalescence in fused quartz capillary tubes. Meanwhile, critical pressures were measured by heating acetone–water solutions to its critical temperature in an autoclave. The standard deviations of critical temperature and critical pressure were 0.55 K and 0.029 MPa, respectively. The results indicate that only one phase exists during mixing of acetone with water. Moreover, P–T–ρ–X data under 15 and 20 MPa in the temperature range of 460–550 K were measured in the autoclave. The relative deviation of density was 0.32%. Volume-translated Peng-Robinson and Soave–Redlich–Kwong state equations were used to illustrate the P–V–T–X relationship of acetone–water solutions, and the Peng–Robinson state equation with an average absolute relative deviation of 1.19% between fitting and experimental densities was found more accurate.
研究领域:
化学工程
·
热力学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY
·
2021
·Vol. 329
·期 2
·1011-1017
·
IF 1.371
Ma Yu,Dou Weixin,Yang Weiting,Yang Weikang,Pan Qinhe
Recently, highly porous metal–organic frameworks (MOFs), with excellent porosity and abundant functional groups, have represented a new addition to the area of capturing uranium ion pollutants. To achieve high adsorption capacity and removal efficiency of uranium, it is significant to modify the morphology of MOF-based adsorbents. In this contribution, two hollow structured ZIF-8 adsorbents were used for the adsorptive separation of uranium from aqueous solution. Both of them showed faster adsorption rate and larger adsorption capacity than pristine ZIF-8, providing the prospect of hollow MOF materials to the application of uranium extraction.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2025
·
IF 2.5
Chenyang Zhang,Xuewei Zhang,Xuerui Yang,Guangli Xiu,JM CHOVELON,Lei Zhou
The photochemical behaviors of fungicides under irradiation differ significantly between leaf surfaces and aqueous solutions. However, few studies have compared the photolysis of fungicides between these two environmental media. In this study, three typical fungicides—kresoxim-methyl (KM), pyraclostrobin (PAS), and cyprodinil (CRL)—were examined using carnauba wax to simulate leaf surfaces The photolysis kinetics, products, and pathways were systematically compared between aqueous solutions and wax films. On wax film, the photolysis rate constants of selected fungicides were observed to be significantly faster than in aqueous solution, with increases of 44, 5 and 36-fold for KM, PAS and CRL, respectively. The primary photolysis pathways on wax films involved photoisomerization and ether cleavage; while the hydroxylation process, commonly observed in aqueous systems, was absent. Toxicity assessments demonstrated that photolysis effectively reduced their ecotoxicities in both systems, with the photolysis on wax film documented as a more profound detoxification process. Moreover, wax film thickness and pesticide additives significantly influenced photodegradation kinetics of all the three fungicides. The present study highlighted the significant influence of environmental media on the photodegradation pathways of pesticides.
研究领域:
环境科学
·
农药化学
✓ 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）