JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY
·
2016
·Vol. 91
·期 11
·2842-2851
·
IF 2.738
Dingsheng Chen,Chaoping Cen,Jinxi Feng,Chunyang Yao,Waiqing Li,Shuanghong Tian,Ya Xiong
BACKGROUND It is of great interest to use pillared clay (PILC) as a cheap support for a selective catalytic reduction (SCR) catalyst. Al-Cr pillared clay (AlCr-PILC) has high thermal stability due to the introduction of polycations of Al. As a support, AlCr-PILC may show a co-catalytic effect in SCR processes because chromium oxide itself is an active SCR catalyst. The aim of this work is to investigate the potential of AlCr-PILC as a new low temperature SCR catalyst support. RESULTS A series of AlCr-PILC with Al:Cr molar ratio varying from 0:4 to 4:0 were successfully synthesized to support manganese and cerium active phase. MnCe/AlCr(2:2)-PILC exhibited the highest NO x conversion close to 100% at 200–300 °C, and more than 90% N 2 selectively over a wide temperature window of 140–300 °C. The catalytic activity of MnCe/AlCr-PILC in terms of both NO x conversion and N 2 selectivity is much higher than those of MnCe/Al-PILC, MnCe/Cr-PILC, AlCr-PILC, and the simple mixed MnCeAlCr, indicating the co-catalytic effect of AlCr-PILC support. CONCLUSION AlCr-PILC is a very promising low-temperature SCR catalyst support. The XRD, XPS, and H 2 -TPR measurements prove that the co-catalytic effect of AlCr-PILC occurred via the strong interaction between MnCe and the AlCr-PILC support. © 2016 Society of Chemical Industry
研究领域:
环境科学
·
催化材料
✓ 已验证
DOI
高影响因子
Carbon Neutrality
·
2024
·Vol. 3
·期 1
·1-16
·
IF 0
Liu Xinghui,Naraginti Saraschandra,Zhang Fuchun,Sathishkumar Kuppusamy,Saxena Kuldeep K.,Guo Xiang
Environmental contamination by hexavalent chromium (Cr(VI)) and antibiotic drug residues pose significant challenges to public health and ecosystems. This study investigates the application of CoTiO 3 /BiVO 4 @MIL-Fe(53) (CT/BV@Fe-MOF) for the reduction of Cr(VI) and degradation of tetracycline (TCL) under visible light. After grafting an iron-based metal–organic framework MIL-Fe(53) on a modified CoTiO 3 /BiVO 4 composite, the photogenerated electrons could easily be transferred from CoTiO 3 to BiVO 4 /Fe-MOF species via interfacial charge transfer. UV–vis diffuse reflectance spectroscopy showed that charge carriers were formed in response to visible light absorption. The effect of different operating parameters, including catalyst load, pH, initial Cr(VI), and TCL concentration, was systematically evaluated during the photocatalytic process. The CT/BV@Fe-MOF composite exhibited 98.7% reduction efficiency in Cr(VI) (50 ppm) and 97.5% degradation efficiency towards TCL (30 ppm) within 90 min, resulting in a greater efficiency than the pristine CoTiO 3 , BiVO 4 , and Fe-MOF materials. The CT/BV@Fe-MOF composite displayed excellent stability over six cycles, highlighting its potential for practical applications. In addition, the plausible degradation pathway of TCL was evaluated using LC-ESI/MS analysis, while the TEST program was utilized to investigate the toxicity of the products generated during the degradation process.
研究领域:
环境科学
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材料科学
·
化学工程
✓ 已验证
DOI
Journal of Cleaner Production
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2022
·
IF 11.072
Sun Qian,Wang Changlong,Zhang Lixin,Yang Yanzhao
The high pathogenicity to organisms and high destructiveness in the natural environment determine the utmost importance of removing Cr(VI) from water. Herein, thiourea crosslinked-amino modified graphene nanoflakes (TAGN) was prepared by simple ring opening reaction and silanization reaction and the Cr(VI) adsorption performance was investigated. Results manifested that TAGN presented three-dimensional porous structure with abundant folds and avoided agglomeration. The adsorption experiments indicated that the optimal test pH value was 2 and the most suitable adsorbent dosage was 1 g/L. Under the optimum adsorption conditions, TAGN exhibited an outstanding adsorption capacity of 193.77 mg/g for Cr(VI) in water. Various characterizations and tests such as Zeta potential , FTIR, XPS as well as isotherms and kinetics revealed that the adsorption of TAGN for Cr(VI) was more consistent with Freundlich isotherm model and pseudo-second-order kinetic model , confirming a multilayer chemisorption process dominated by multiple combination mechanisms: electrostatic interaction, reduction reaction, complexation and hydrogen bonding interaction. Under the condition of coexistence of multiple metal ions , the TAGN could still maintain superb selectivity of 63.9% towards Cr(VI). After ten cycling test, 81.8% removal efficiency of Cr(VI) was guaranteed. Therefore, TAGN possessed high adsorption capacity , excellent selectivity and prominent cyclic regeneration ability. This work provided a promising nanosorbent for the field of water cleaning, especially for the elimination of heavy metal ions .
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
MICROCHEMICAL JOURNAL
·
2024
·
IF 4.9
Yu Li,Zhenhua Xiong,Siying Zhang,Long Zhang,Li Sheng,Xingli Ding,Liang Shen,Jingkun Xu,Jinglan Wang,Ge Zhang
Degradable fluorescent film sensors are highly ideal for real-time outdoor detection of heavy metal ions and offer the advantage of preventing secondary contamination, aligning with the principle of sustainable development. In this work, we constructed a degradable fluorescent hydrogel for the specific detection of Cr(VI) ions, utilizing poly(1-pyrene butyric acid) (PPBA) as the sensing moiety and sodium alginate (SA) as the cross-linking substrate. The porous network structure of the PPBA-SA film provided enhanced ion transport channels and active sites, thereby reducing fluorescence response time and augmenting detection sensitivity. The PPBA-SA film exhibited rapid and selective recognition of Cr(VI) ions among a panel of 16 anions and 22 cations, achieving an impressive limit of detection of 1.99 nM. Moreover, we successfully applied this platform to detect Cr(VI) ions in four different vegetable samples. Notably, the PPBA bound with Cr(VI) ions could be effortlessly removed from the film, and the substrate underwent rapid degradation within 24 h, attaining a degradation rate of 72.4 %. This work provides an innovative and effective strategy for fabricating green and sustainable fluorescent sensors.
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 Water Process Engineering
·
2024
·
IF 6.3
Junjie Su,Qi Yang,Zhihu Zhang,Ziyue Zhang
Nowadays, Ni/Fe bimetallic nanocomposites have shown great potential for removing Cr(VI). However, the action of Ni 0 in Cr(VI) removal is still controversial, which was studied in this work. In this study, Ni/Fe@Fe 3 O 4 -g-C 3 N 4 (NFFOCN) nanocomposites were applied to remove Cr(VI) from aqueous solutions and characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and other methods. Batch experiments were conducted to evaluate the Cr(VI) removal performance. Experimental results demonstrated that under optimal operating conditions (pH 5.5, 10 mg/L Cr(VI), 0.3 g/L NFFOCN, 30°C), a Cr(VI) removal efficiency of 90.78% was achieved within 50 min. Theoretical maximum adsorption capacity was calculated to be 36.101 mg/g. Combining experimental and characterization results, it could be concluded that Cr(VI) removal was attributed to the synergistic effect of the NFFOCN components. Ni 0 not only participated directly in the reduction of Cr(VI) as an electron donor, but also converted the corrosion product H 2 of nano-zero-valent iron (nZVI) into highly reducible atomic hydrogen (·H) to remove Cr(VI). Additionally, Ni 0 could form a primary battery with nZVI, facilitating the electron transfer between nZVI and Cr(VI). NZVI and its derivatives, Fe 2+ ions and green rust, were responsible for Cr(VI) reduction. Furthermore, the presence of Fe 3 O 4 and carbon nitride (g-C 3 N 4 ) improved the stability and reactivity of the nanocomposites.
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
Carbon Letters
·
2025
·
IF 5.8
Ren Zhiyuan,Chang Wei,Tian Ke,Yao Peiqi,Liu Bin,Li Yunfeng,Zhang Runze
This study details the synthesis and characterization of phosphorus-sulfur co-doped graphitic carbon nitride quantum dots (PSQ) and their integration into g-C 3 N 4 (CN) to form PSQ/CN composites for the enhanced photocatalytic reduction of Cr(VI) and fluorescence detection. Incorporating PSQ into CN was found to significantly improve light absorption, narrow the band gap, and enhance charge separation efficiency. Notably, the composite material exhibits superior photocatalytic performance, especially in acidic environments. Photocatalytic assessments utilizing Cr(VI) demonstrated that the PSQ/CN composite outperformed both undoped and singly doped materials, indicating its superior photocatalytic activity. Additionally, phosphorus-sulfur co-doping markedly increased the fluorescence quantum yield of PSQ. The fluorescence intensity exhibited a linear decrease with increasing Cr(VI) concentrations, enabling sensitive and selective detection of Cr(VI) with a detection limit as low as 1.69 μmol/L. Collectively, the PSQ/CN composite and PSQ highlight their potential for photocatalysis and fluorescence-based detection of Cr(VI), providing high sensitivity, selectivity, and synergistic interactions within the composite material.
研究领域:
材料科学
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环境科学
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Inorganic and Organometallic Polymers and Materials
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2024
·
IF 3.9
Liu Yuhao,Wang Xuyi,Chen Jiayue,Wang Hua,Cheng Ming,Zheng Dan,Zhang Beibo,Geng Liang,Chen Liping,Jia Yingbin,Wang Luoxin
In this work, we synthesized core-shell NH 2 -UiO-66@UiO-67 via a solvothermal method to achieve controlled assembly of amino-modified UiO-66 and UiO-67 at micro and nano scale. NH 2 -UiO-66@UiO-67 exhibited notable visible light responsiveness and an increased specific surface area.In addition, it demonstrated outstanding performance in Cr(VI) removal, which can be attributed to the photocatalytic conversion of Cr(VI) into less toxic Cr(III), and the adjustable pores and large specific surface area facilitating Cr(III) adsorption. Notably, it exhibited a robust removal efficiency across a wide pH range of 2.0 to 10.0. Specifically, at pH = 2.0, the Cr(VI) solution with a concentration of 60 mg/L was completely removed within 140 min. The results show that the adsorption of core-shell NH 2 -UiO-66@UiO-67 meets the pseudo-second-order adsorption kinetics and has the ability of photocatalytic reduction of Cr (VI).
研究领域:
材料科学
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环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2019
·
IF 5.155
Zhaoyang Li,Yongjie Zhao,Qing Guan,Qian Liu,Sara Khan,Leilei Zhang,Xianze Wang,Lei Chen,Xia Yang,Mingxin Huo
Photocatalytic reduction of nitrate has attracted much attention recently, however, low efficiency and difficult separation have limited its application in practice. In this study, the novel direct dual Z-scheme AgBr(Ag)/MIL-101(Cr)/CuFe 2 O 4 (AB/M/CFO) was fabricated by the hydrothermal technology combined with the photodeposition method for the first time. The AB/M/CFO exhibited the highest nitrate conversion and nitrogen selectivity (79.9% and 94.5%, respectively) compared to AgBr(Ag)/MIL-101(Cr), MIL-101(Cr) and CuFe 2 O 4 for 30 min UV-light irradiation. The dual Z-scheme of AB/M/CFO enhanced electron transfer and charge separation, which was proved by transient photocurrent responses, leading to a significant improvement in photocatalytic efficiency. Meanwhile, after four cycles, the AB/M/CFO photocatalyst also displayed a strong magnetic separation ability and excellent recycling stability. Furthermore, the excitation and electron transfer process over dual Z-scheme AB/M/CFO photocatalytic material were proposed, based on the radical trapping experiments. Our work provides a new strategy to construct dual Z-scheme MOFs-based materials that have promising applications in photocatalytic reduction of pollutants.
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 APPLIED POLYMER SCIENCE
·
2022
·Vol. 139
·期 34
·e52799
·
IF 3.057
Wei Jia,Jiang Du,Ming Jiang,Mengying Zhang,Enlin Han,Hongqing Niu,Dezhen Wu
In order to overcome the shortcomings of nanofiber membranes such as low mechanical properties and poor acid resistance, amino-rich functionalized polyimide (PI)-polyethyleneimine (PEI) fibers were successfully prepared in the study. The structure and morphology in each functionalization step were characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), static contact angle, attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), and X-ray photoelectron spectroscopy (XPS) measurements. The adsorption kinetics analysis showed that the adsorption process followed a pseudo-second-order model, and the adsorption isotherm could be described better by the Langmuir model indicating the adsorption process was mainly chemical and homogeneous monolayer adsorption. Furthermore, the maximum adsorption capacity based on the Langmuir model was about 50 mg g −1 , and the calculated thermodynamic parameters demonstrated an endothermic process. Meantime, the PEI-grafted PI fibers also exhibited good regeneration performance and stable tensile strength during recycling tests process. In the first 3 adsorption–desorption cycles, the removal efficiency and tensile strength of PI-PEI fibers could be maintained up to 60.44% and 89.29% of the initial adsorption, respectively. This work achieved the function of removing Cr (VI) by combining the excellent high temperature resistance, acid resistance, and mechanical properties of PI fibers.
研究领域:
材料科学
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环境工程
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化学工程
✓ 已验证
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2015
·
IF 2.587
Zhiqiao He,Lixian Jiang,Da Wang,Jianping Qiu,Jianmeng Chen,Shuang Song
A series of fluorinated anatase TiO2 nanosheets with dominant {001} facets were synthesized to oxidize p-chlorophenol (PCP) and reduce Cr(VI) simultaneously under visible light. The {001}/{101} surface facets ratio of TiO2 was controlled by varying the initial HF concentration, and fluorine-free samples were obtained by alkaline-washing. A synergistic effect among TiO2, Cr(VI), and PCP was observed, which is ascribed to effective trapping of photogenerated electrons and holes by Cr(VI) and PCP, respectively. A maximum synergistic effect was obtained at a molar ratio of [PCP] to [Cr(VI)] of one. Using X-ray diffraction, X-ray photoelectron spectroscopy, electron paramagnetic resonance spectroscopy, field-emission scanning electron microscopy, transmission electron microscopy, and Brunauer–Emmett–Teller analyses, the optimum ratio of exposed {001} to {101} facets for TiO2 was determined to be 80:20 because of selective transfer and charge balance of photogenerated carriers. Surface fluorination facilitates the formation of oxygen vacancies and unsaturated Ti atoms, which is useful for visible light activity induction, extending the lifetime of photogenerated electron-hole pairs, and enhancing the rate of PCP oxidation and Cr(VI) reduction.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2025
·
IF 9
Fulin Wang,Helin Hua,Hui Jia,Dingying He,Zhongyou Jiang,Jiaxin Cao,Shanshan Dong,Zhenxing Zeng,Suhua Chen
The construction of heterojunction is considered to be an effective way to promote the photocatalytic activity, while it is always challenging due to the mismatched lattices of heterojunctional materials and results in an unsatisfactory enhancement of charge carrier separation. It is critical to overcome that lattice mismatch and establish charge transfer channels in heterojunction for achieving high charge transfer and separation. In this study, a red phosphorus/phosphorus doped graphitic carbon nitride (RP/P-CN) type I heterojunction was constructed to boost interfacial charge transfer for Cr(Ⅵ) photoreduction through in situ growing RP on g-C 3 N 4 nanosheets. The formed P − N bonds around interfaces in the RP/P-CN allowed photoexcited charge to rapidly transfer from the conduction band of P-CN to that of RP, which contributed to the significant achievement of Cr(Ⅵ) reduction. The constructed interfacial charge transfer channels largely promoted the photoexcited charge carrier separation in the RP/P-CN. Additionally, the simultaneous RP formation and P doping significantly enhanced the visible light response and the adsorption efficiency of Cr(Ⅵ). As a result, RP/P-CN 1:5 could achieve 99.1 % removal of Cr(Ⅵ) after 20-min visible light irradiation with an achieved apparent kinetic rate constant (k app ) of 0.2289 min −1 , which were much better than the 19.2 % of Cr(Ⅵ) removal by pure g-C 3 N 4 and presented a 21-fold higher k app than pure g-C 3 N 4 (0.0108 min −1 ) achieved, respectively. This study provides a new strategy to design an efficient g-C 3 N 4 based metal-free heterojunction for Cr(Ⅵ) photoreduction.
研究领域:
材料科学
·
环境科学
·
光催化
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Xiaolu Fan,Tianyun Wu,Xue Wu,Bo Jiang,Jing Xiong,Fei Li,Shupeng Li,Lei Zheng,Yunpeng Liu,Dayi Zhang
Chemical stabilization is a frequently used method to stabilize heavy metals in soils, however suffering from the reagent overdosage and exorbitant cost due to the insufficient reactions between chemical stabilizers and heavy metals. In this work, we innovated an economy and energy efficient stabilization technique, namely steam flash heating (SFH), and investigated its stabilization performance and mechanisms for hexavalent chromium [Cr(VI)]. SFH can efficiently promote Cr(VI) reduction by both soil organic matter and chemical stabilizers. From thermophysical analysis, SFH efficiently enhanced the molecular contact and accelerated mass transfer in porous soils, resulting in the promoted transformation of Cr(VI) into OM-Cr(III), Fh-Cr(III), and Cr(OH) 3 from Cr/Fe/S/C XANES results. By replacing partial chemical stabilizers with soil organic matter in Cr(VI) reduction, SFH decreased nearly 70.7% of cost and 38.1% of CO 2 emission. Besides, Mn XANES results unraveled that MnO x was reduced by soil organic matter and chemical stabilizers with the aid of SFH, and this process decreased the risk of Cr(III) re-oxidation and benefited long-term Cr stability. These results proved that SFH could efficiently immobilize Cr with low energy consumption, low economic cost, high stabilizer efficiency, and low re-mobility risk, exhibiting applicable potential in the remediation of Cr-contaminated soils. This study revolutionized chemical stabilization by SFH and unraveled the underlying mechanisms of Cr immobilization in contaminated soils.
研究领域:
环境科学
·
土壤修复
✓ 已验证
DOI
高影响因子