JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2021
·
IF 8.128
Jia Wen,Xiaohong Hu
Recently, the developments of MOFs and their applications on heavy metal removal have attracted much attention. In this paper, we focused on the influence of co-existing ions on the adsorbability of epigallocatechin gallate (EGCG) modified ZIF-8 in a multi-metal system (Cd(II), Cu(II), Ni(II), and Cr(VI)). It was found that the adsorption of Cd(II), Cu(II), Ni(II), and Cr(VI) on the ZIF-8-EGCG fitted well with the pseudo second-order kinetic model and Langmuir isotherm. The adsorption selectivity of ZIF-8-EGCG in the mixed metal solution followed the order of Cu(II) ≫ Cr(VI) > Cd(II) > Ni(II). Besides, Cu(II) was the most attractive substance with a maximum capacity of 232.97 mg·g −1 . Copper also disturbed the adsorption of Cd(II) and Ni(II) and contributed the most to the Cr(VI) removal. The natural anions (e.g., Cl − , NO 3 – , AsO 2 − , SO 4 2− ) significantly impeded Cr(VI) adsorption, while low concentrations of natural cations (e.g., K + , Na + , Ca 2+ , and Mg 2+ ) facilitated the adsorption of Cd(II), Cu(II) and Ni(II).
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2020
·Vol. 28
·期 10
·12459-12473
·
IF 3.056
Guo Tongtong,Yang Shuang,Chen Yunning,Yang Lu,Sun Yingnan,Shang Qingkun
In this paper, the kinetic characteristics and cycle stability of Fe-complex/TiO 2 in the process of degradation of phenolic pollutants and reduction of heavy metal Cr(VI) were studied systematically. First, the structural characteristics and photocatalytic activities of Fe(III)-(8-hydroxyquinoline-5-carboxylic acid)-TiO 2 (Fe-HQC-TiO 2 ) nanoparticle to degrade phenolic pollutants and reduce Cr(VI) simultaneously had been investigated. Compared with the single degradation, the efficiency of synergistic degradation/reduction had been improved and the degradation/reduction rate had been obviously accelerated. In particular, the cyclic stability of Fe-HQC-TiO 2 photocatalyst decreased obviously when it was used to reduce Cr(VI) alone, but it could still keep above 90% after three cycles when it was used for reduction of Cr(VI) and degradation of phenol synergistically. Second, to Fe-HQS/TiO 2 nanoparticle or Fe-HQS/TiO 2 nanotube (HQS (8-hydroxyquinoline-5-sulfonic acid)), the synergistic degradation/reduction (2,4-dichlorophenol/Cr(VI)) efficiencies were always greater than those of a single degradation/reduction and the time was greatly reduced. All the results indicated that there were interactions between Cr(VI) and phenol or 2,4-dichlorophenol in the photocatalytic process. The possible mechanism of synergistic accelerated degradation of phenolic compounds and reduction of Cr(VI) was proposed by analyzing and testing the surface characteristics of photocatalyst and the properties of photocatalytic system during the synergistic degradation/reduction.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY
·
2020
·
IF 4.872
Jiahong Wang,Yao Chen,Tongtong Sun,Atif Saleem,Chuanyi Wang
A novel amino-functionalized magnetic adsorbent (Fe 3 O 4 @C@DETA) was developed for adsorption of Cr(III) and Cr(III)-EDTA from wastewater. Fe 3 O 4 @C@DETA were successfully prepared by modification of Fe 3 O 4 @C with diethylenediamine (DETA), which exhibits a core-shell structure and sufficient saturation magnetization. Fe 3 O 4 @C@DETA exhibits much better adsorption performance for Cr(III) and its chelates than the Fe 3 O 4 @C because of newly introduced amino active sites. The enhanced adsorption capacity of Fe 3 O 4 @C@DETA for Cr(III) is 44.74 mg g −1 (at 25 °C and pH 3.0), which is due to the surface coordination with the newly introduced amino functional sites. The Cr(III)-EDTA anions as a whole was adsorbed through the electrostatic interaction with protonated amino species of the Fe 3 O 4 @C@DETA and have maximum adsorption capacity of 47.27 mg g −1 (at 25 °C and pH 3.0). The adsorption data of free and EDTA coordinated Cr(III) were followed the Langmuir equation, while the adsorption dynamics was well explained by pseudo second order model indicating the chemical nature of adsorption process. The higher concentration of Ca 2+ ions in the wastewater compete for adsorption sites and inhibit the Cr(III) removal, while on other hand Ca 2+ ions promotes the adsorption of Cr(III)-EDTA, because of electrostatic interaction with adsorbent active sits. Furthermore, the adsorbent can be easily separated by external magnetic field and regenerated in acidic solution. The adsorbent is stable, recyclable and have more than 75% regeneration efficiency and can be repeatedly used in the adsorption process.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2020
·
IF 10.652
Lixiang Zhang,Pan Li,Luping Feng,Xi Chen,Jiatian Jiang,Sheng Zhang,Anchao Zhang,Guofu Chen,Hua Wang
Visible-light-driven and ultra-stable CoS x /CdS photocatalysts were controllably fabricated by the ZIF-67-templated one-pot solvothermal route for highly efficient photocatalytic Cr(VI) reduction. It was discovered that the resulting CoS x /CdS composites could present different photocatalytic activities controllably depending on the CoS x -to-CdS molar ratios used. The one with 1/16 M ratio could display the highest photocatalytic reduction performance for Cr(VI) with the efficiency up to 100% within 30 min, which is 5.6-fold and 2.1-fold higher than that of pristine CoS x and CdS, respectively. Herein, the components of CoS x and CdS with well-matched energy-band structures might serve separately as the electrons donor and the holes quencher to prolong the lifetime of photogenerated electrons in CoS x /CdS composites. A direct Z-scheme heterojunction could be thus constructed for promoting the charge carrier transferring with the improved redox abilities, leading to the robust photocatalysis of CoS x /CdS photocatalyst. Moreover, the developed CoS x /CdS photocatalyst could present superior stability with the structure and activity well survived after five photocatalytic cycles. This work may pave the way towards the controllable construction of a direct Z-scheme photocatalytic system by synergistically combining two kinds of components with matched energy-band structures, achieving the enhanced photocatalysis for the wide applications in the environmental remediation field.
✓ 已验证
产品关联
DOI
高影响因子
TALANTA
·
2020
·
IF 5.339
Wei Zou,Chenghui Li,Jing Hu,Xiandeng Hou
A novel and sensitive method for the selective determination of Cr(VI) and non-chromatographic speciation of Cr(VI) and Cr(III) was developed based on chemical vapor generation (CVG) in KBH 4 -acid system for sample introduction into an inductively coupled plasma mass spectrometer (ICP-MS) for detection. The CVG of Cr(VI), rather than Cr(III), was found to be remarkably enhanced in the presence of sodium diethylaminodithioformate (DDTC). After the oxidation of Cr(III) to Cr(VI) by KMnO 4 , the quantitation of Cr(III) could be obtained based on the difference between the concentration of total chromium and that of Cr(VI). Parameters affecting the CVG reaction and determination of Cr(VI) were evaluated in detail, including the concentrations of DDTC, hydrochloric acid and KBH 4 , the sample flow rate , as well as the length of reaction and transferring tubing. Under optimal conditions, the CVG efficiency and the limit of detection (LOD) of Cr(VI) were found to be 28% and 0.2 ng mL −1 , respectively. The relative standard deviations for seven replicate measurements of 20 ng mL −1 of Cr(Ⅵ) was 1.8%. Furthermore, with excess DDTC (100 μg mL −1 ) added to the test solutions, possible interferences from Cu 2+ (up to 400 ng mL −1 ) could be eliminated. The proposed method was thus successfully applied to the determination of Cr(VI) in three real water samples and one certified reference water sample, as well as two simulated water samples of Cr(VI) and Cr(III), all with satisfactory results. The possible reasons were discussed for the varied degrees of enhancement between Cr(III) and Cr(VI).
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2020
·
IF 9.038
Qiuyan Luo,Hanmeng Yuan,Min Zhang,Ping Jiang,Ming Liu,Dong Xu,Xin Guo,Yiqiang Wu
To effectively detect and remove environmentally hazardous Cr(VI), a novel 3D porous fluorescent hydrogel was synthesised using amino-modified carbon dots and cellulose nanofibers. The synthesised fluorescent hydrogel was characterized to determine its morphology, crystalline structure, chemical composition and optical property using scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, UV–vis absorption spectroscopy and photoluminescence spectroscopy. The sorption properties of the synthesised fluorescent hydrogel were further analyzed. The maximum sorption capacity for Cr(VI) reached 534.4 mg/g, the adsorption isotherm was well fitted using Langmuir model, and the adsorption kinetics were well fitted using a pseudo-second-order model. The sensing ability of the synthesized hydrogel for Cr(VI) was also determined. Furthermore, the mechanism of Cr(VI) sorption and sensing was determined. Accordingly, this novel 3D porous fluorescent hydrogel was identified to be a promising sorbent with advantages of excellent sorption and sensing abilities for environmentally hazardous Cr(VI).
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMOSPHERE
·
2019
·
IF 5.108
Kun Wang,Yuebing Sun,Jingchun Tang,Juan He,Hongwen Sun
A novel ball milled Fe 0 -biochar composite was synthesized by ball milling the mixture of biochar (pyrolyzed at 300 °C, 500 °C, and 700 °C) and micron grade iron powder. FTIR, SEM , TEM-EDS, XRD , and XPS were applied to characterize this composite. XRD results showed that iron carbide phase was formed during the ball milling process. The ability of this synthesized composited to remove aqueous Cr(VI) was tested. Removal rates of Cr(VI) (49.6%, 65.8%, and 97.8%, respectively) by ball milled Fe 0 -biochar composite consisting of biochar pyrolyzed at 300 °C (300BMFe 0 -BC), 500 °C (500BMFe 0 -BC), and 700 °C (700BMFe 0 -BC) were much higher than those (19%, 11%, and 4%, respectively) by pristine biochar pyrolyzed at 300 °C (300BC), 500 °C (500BC), and 700 °C (700BC). Cr(VI) removal rate by 700BMFe 0 -BC increased from 15.4% to 97.8% when prolonging ball milling time from 6 h to 48 h. Ball milling promoted the combination of Fe 0 and biochar as well as reduced the hydrodynamic diameter of the composite. Acidic conditions favored Cr(VI) removal. Ball milling exposed the functional groups of biochar and improved its Cr(VI) removal rate. Raman spectra showed that the degree of graphitization in 700 °C ball milled biochar (700BMBC) was the highest. Electrochemical analysis demonstrated that 700BMBC had the highest electron transfer capacity. In the presence of Fe 0 , graphitized structure in 700BMBC acted as an electron conductor, facilitating electron transfer from Fe 0 to Cr(VI). Ball milling also destroyed the surface iron oxide layer to regenerate the composite.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Environmental Science-Nano
·
2023
·Vol. 11
·期 1
·229-240
·
IF 7.3
Wen Lu,Chen Wang,Yuxuan Bai,Chengde Xie,Zhixiong Zhang,Wenhui Song,Jianjun Wang
Polluted wastewater containing organic pollutants and heavy metals is increasing and harms environmental ecosystems and human health. Designing and producing an efficient photocatalyst is therefore crucial for treating polluted wastewater. In this study, electron-deficient benzothiadiazole was used as the electron acceptor, and electron-rich thiophene as the electron donor using a solvothermal method. The successful preparation of a novel visible-light responsive donor–acceptor type covalent organic framework (HDU-26) has been demonstrated using various characterization techniques. The conjugated structure of the electron-donating and electron-accepting units promoted the charge transfer of the HDU-26 photocatalyst, effectively reduced the band gap, and suppressed the electron–hole (e−–h+) complexation. The photocatalytic performance was investigated under the influence of different parameters. Under optimal conditions, HDU-26 achieved a photocatalytic reduction efficiency of up to 99.5% for Cr(VI). Over five reaction cycles, HDU-26 was still able to maintain a high level of photocatalytic activity, with the Cr(VI) removal rate reaching 97.4%. The major active species for the photocatalytic reduction of Cr(VI) were e− and ·O2− radicals. In addition, the oxidation of organic matter results in an increase in photogenerated e−–h+ separation. Moreover, the photocatalytic rate of HDU-26 was significantly accelerated due to the synergistic effect in the mixed system of Cr(VI)/organic pollutants (RhB, MB, MO). In conclusion, the high availability of active sites, excellent stability, and recyclability of HDU-26 indicate its potential applications for removing organic pollutants and heavy metal ions from contaminated wastewater.
✓ 已验证
产品关联
DOI
高影响因子
POLYMER ENGINEERING AND SCIENCE
·
2023
·Vol. 63
·期 11
·3891-3905
·
IF 3.2
Junhui Si,Yuanchang Deng,Changxiong Gong,Zhixiang Cui,Qianting Wang
Deacetylated cellulose acetate/thermoplastic polyurethane@graphene oxide (DA/TPU@GO) nanofibrous membranes were prepared through the combination of electrospinning, deacetylation, and ultrasound-assisted surface treatment techniques. The morphology, wettability, and mechanical properties of composite nanofiber membranes were studied via SEM, TEM, water contact angle measurements, and mechanical tests. Moreover, the adsorption capacity and mechanism of DA/TPU@GO nanofiber membranes for methylene blue and chromium (Cr (VI)) were analyzed. The introduction of active sites from GO led to a significant increase in the adsorption capacity of the DA/TPU@GO composite membranes compared with the DA/TPU composite nanofiber. The composite membrane featured adsorption capacities of 152.7 mg/g (25°C, pH 3) and 122.1 mg/g (25°C, pH 7) for Cr (VI) and methylene blue, respectively, which are higher than most other composite GO-based adsorbents. The adsorption mechanism of the DA/TPU@GO composite membrane was consistent with the Langmuir isotherm and second-order kinetic models. Therefore, the DA/TPU@GO composite nanofiber membrane served as an effective adsorbent with broad application prospects in the sewage treatment field owing to its excellent adsorption capacity. Highlights Nanofibers were prepared for the absorption of methylene blue (MB) and Cr (VI). Nanofibers exhibited adsorption capacities of 152.7 and 122.1 mg/g for Cr (VI) and MB. Adsorption mechanism follows Langmuir isotherm and second-order kinetic models. Nanofibers have wide potential applications in sewage treatment.
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2023
·
IF 5.2
Qifa Wan,Faming Zhang,Yifeng Xiong,Caiyun Shang
Using a simple and scalable solid-state synthesis process, a series of spinel-structured high-entropy oxides were systematically designed and synthesized in a Co–Mn–Fe–Cr–Ni–Zn–O system. These included (Co,Mn,Fe,Cr) 3 O 4 , (Co,Mn,Fe,Ni) 3 O 4 , (Co,Mn,Fe,Cr,Ni) 3 O 4 , (Co,Mn,Fe,Zn) 3 O 4 , (Co,Mn,Fe,Cr,Zn) 3 O 4 , (Co,Mn,Fe,Ni,Zn) 3 O 4 and (Co,Mn,Fe,Cr,Ni,Zn) 3 O 4 . The phase, microstructure and color evolution of 1/3Co 3 O 4 –1MnO-1/2Fe 2 O 3 -1/2Cr 2 O 3 –1NiO powders were studied without ZnO addition. These underwent four phase evolution processes and three color evolution processes before forming the final phase of black, octahedral (Co,Mn,Fe,Cr,Ni) 3 O 4 powders. The formation of an intermediate phase of (Co,Mn,Fe) 3 O 4 medium-entropy oxide powders served as the foundation for the creation of other high-entropy oxide powders. The infrared radiation properties of these synthesized medium and high-entropy oxides powders were evaluated in the near-infrared region at room temperature. Among these synthesized powders, the infrared emissivity values of (Co,Mn,Fe) 3 O 4 , (Co,Mn,Fe,Ni) 3 O 4 and (Co,Mn,Fe,Cr,Ni) 3 O 4 powders exceeded 0.8. All the synthesized powders exhibited excellent thermal stability after being annealed at high temperatures. Notably, after being annealed at high temperatures, the infrared emissivity values of these synthesized powders increased markedly without degradation, surpassing a value of 0.8, and displayed potential for applications in the field of high-temperature infrared energy savings.
✓ 已验证
产品关联
DOI
高影响因子
Journal of Cleaner Production
·
2023
·
IF 11.1
Xiunan Cai,Qingling Liu,Qing Yang,Fuzheng Fu,Yanjuan Zhang,Tao Gan,Huayu Hu,Zuqiang Huang
To effectively utilize the hazardous industrial solid waste manganese residue (MR), a MR-derived Fe 2 O 3 -baesd photocatalyst with efficient charge transfer, abundant reactive sites and high redox performance was developed for simultaneously removing organic pollutants and heavy metals . Herein, a novel “confined growth” strategy was proposed to fabricate an amorphous MnO 2 decorated α-Fe 2 O 3 @geopolymer sphere (A-MnO 2 /Fe 2 O 3 @GS) Z-scheme heterojunction by ion exchange method, which was used as a photo-Fenton catalyst for efficiently reducing Cr(VI) and degrading ciprofloxacin (CIP). Characterization results reveal that the 3D hydrangea-like MnO 2 with low crystallinity could not only capture and accelerate electron transfer but also act as an electron conduction bridge and a surface oxygen adsorption site, resulting in efficient separation and utilization of charge. More importantly, the photocatalytic reduction capacity was greatly enhanced in Z-scheme heterojunction owing to the lower conduction band potential of MnO 2 . A-MnO 2 /Fe 2 O 3 @GS showed excellent photocatalytic activity with CIP removal of 99.1% within 40 min and Cr(VI) removal of 97.6% within 50 min, which were 8.13 and 3.47 times higher than those catalyzed by Fe 2 O 3 @GS, respectively. This can be ascribed to the formation of intimate interface, internal electrostatic field , and rich structure defects in the Z-scheme heterojunction. This work offers a new idea to construct Z-scheme photocatalysts with high reactivity for environmental modification.
✓ 已验证
产品关联
DOI
高影响因子
MICROCHIMICA ACTA
·
2023
·Vol. 190
·期 3
·1-12
·
IF 5.7
Chu Zhe,Gong Wenxue,Muhammad Yaseen,Shah Syed Jalil,Liu Qing,Xing Linguang,Zhou Xueyun,Liu Ying,Zhao Zhenxia,Zhao Zhongxing
A bimetallic polycrystalline sensor (Cr/Fe-SNCM) having nanosized and high dispersion was designed and used for the electrochemical simultaneous determination of dopamine (DA) and uric acid (UA). Catalytic nanosized Cr/Fe were highly anchored on N/S/O-contained porous carbon with high dispersion and polycrystalline Cr/Fe via energetic mechanochemical method and high-temperature carbonization. The obtained Cr/Fe-SNCM exhibited high graphitized carbon supporter and endowed high electron transport and signal output for the whole sensor. Moreover, highly dispersed Cr/Fe sites and the polycrystalline form (metal-N/S/O) efficiently enhanced the catalytic reaction, leading to a limits of detection (based on the 3σ/m criterion) of 25.8 and 22.5 nM for DA and UA, respectively. This is 1–2 orders of magnitude lower than many state-of-the-art reported sensors. The Cr/Fe-SNCM 1.0 sensor exhibited wide working range (0.1 to 10.0 μM), high recovery (96–103%) and low relative standard deviation (RSD = 3.2–4.7%) for DA and UA in real serum samples, possessing high significance for practical large-scale applications. Graphical abstract
✓ 已验证
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）