CHEMOSPHERE
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2023
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IF 8.8
Jianyong Zhao,Xiangchao Meng
A novel slant perforated mesh-plate photoreactor (SPPR) was designed and fabricated. The central assembly of SPPR was an array of slant perforated mesh-plate coated with TiO 2 (P25). The performance of SPPR in water detoxification was evaluated with regard to the degradation of phenol as the target pollutant. The effects of slant plate tilt angle (α) and perforated plate opening aperture diameter on SPPR performance were investigated and analyzed. The photocatalytic performance of SPPR increased with decreasing α. The SPPR with an α of 15° and a pore size of 1 mm showed the best performance with 9.17 h required to reach 80% of phenol degradation (4-L, initial concentration: 15 mg/L). The mass transfer was introduced into the kinetic reaction model, and mass transfer coefficients were calculated for SPPRs with different structures. Flow rate and initial pollutant concentration were investigated for their effects on degradation efficiency. In addition, the activity of SPPR under natural sunlight has also been tested to explore its potential to be applied in practice.
研究领域:
环境科学
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化学工程
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产品关联
DOI
PubMed
高影响因子
Chemical Engineering and Processing-Process Intensification
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2019
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IF 3.031
Suqi Zhang,Jie Zhang,Jian Sun,Zhiyong Tang
A novel capillary microphotoreactor (MPR) packed with TiO 2 -coated glass beads was developed in this work and its photocatalytic performance was evaluated using degradation of methylene blue (MB) as a model reaction. As compared to conventional wall-coated MPR, the use of glass beads as packing material not only provides a larger surface area for catalyst immobilization and shortens the mass transfer route, but also introduces flow perturbation. An appropriate size of glass beads should be chosen for packing because there is a tradeoff between increased catalysts coating area and decreased light penetration. It was found out that nearly 100 % degradation efficiency could be achieved in 80# glass beads packed MPR within short residence time (20 s), which was more than 2 orders of magnitude larger than value obtained in wall-coated MPR under the same operational conditions. Moreover, the packed MPR showed good durability, which declined by about 17 % after 6 h of operation and then remained stable for next 19.5 h.
研究领域:
环境科学
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化学工程
✓ 已验证
DOI
高影响因子
Journal of Flow Chemistry
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2021
·Vol. 12
·期 1
·41-49
·
IF 2.786
Lan Zhou,Lu Yangcheng
Benzyl iodide, an important organic synthesis intermediate, has high reaction activity as well as high commercial value due to its weakest carbon-halogen bond. However, the development of direct iodination of toluene for benzyl iodide is limited by the fact that the C-I bond is easily decomposed under heat or light. In this work, the photoiodination of toluene to synthesize benzyl iodide in the I 2 /PhI(OAc) 2 / t BuOH system was carefully investigated in the flow photoreactor under LEDs irradiation. The reaction window suitable for the reaction kinetic characteristics recognition was revealed with the considerations of the effects of various parameters including light color, light intensity, reaction temperature, residence time, and usage of each substrate. And an optimized result is to achieve 95.83 % of yield and over 99 % of selectivity under a red light with 2.05 mW/cm 2 of light intensity at 80 o C after 15 min reaction. The reaction kinetic model coupling the iodination reaction (photo and thermal reaction) with the decomposition reaction is established, which fits well the experimental results and provides fundamentals for process design and optimization. Graphical abstract
研究领域:
有机化学
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化学工程
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DOI
高影响因子
Journal of Cleaner Production
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2023
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IF 11.1
Tan Meng,Xiao Su,Peizhe Sun,Wenjun Sun,Domenico Santoro,Hong Yao,Hui Wang
UV-based advanced oxidation processes (UV-based AOPs) via photolysis of radical precursor chemicals (RPCs) are among the most effective technologies for eliminating trace organic contaminants in water treatment facilities. However, mathematical discussions on the kinetics and energy consumption for the engineering photoreactor set-up of UV-based AOPs, especially the newly proposed UV-based AOPs (e.g., UV/persulfate, UV/chlorine and UV/chloramine), are scarce. In this study, a photoreactor with reflective sleeves was mathematically characterized and validated using clean and complex water matrices, and approaches for measuring effective light absorbance by RPC ( I RPC ) and the reflectance of the photoreactor wall ( η ) were proposed. By applying I RPC and η , and employing geosmin as a model compound, energy optimization of the UV-based AOPs was conducted based on an updated kinetic model . A new equation was derived for UV/H 2 O 2 to obtain the most cost-effective RPC dose regarding EE/O ( electric energy required for one order of contaminant removal ) ( C opt-EE/O ). This equation was then successfully extended to other UV-based AOPs (including UV/persulfate, UV/chlorine, and UV/chloramine). The balance between the treatment goals and operational costs was also discussed. Overall, the new concepts and approaches proposed in this study may aid in the energy optimization and reduce RPC consumption of various UV-based AOPs for engineering applications .
研究领域:
环境科学
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水处理工程
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产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2023
·
IF 4.2
Jintao An,Qianrui Lv,Yuchao Wang,Wenbo Yang,Shengyang Tao,Lijing Zhang,Alexander A. Miskevich,Valery A. Loiko
Accurate, stable, and reproducible photocatalytic reaction systems remain a major challenge when performing photocatalytic mechanism studies. In this paper, we designed and built a standard photocatalytic reactor to realize the precise adjustment of each parameter related to the photoreaction to meet the demand for the accurate study of photochemical reaction mechanisms and can realize the personalized settings for different photochemical reactions. Based on this standard reactor, the influence of each independent parameter on the conversion rate of the reaction was studied based on the model reaction of 9,10-diphenylanthracene oxidation, and a mathematical model of the coupling influence of multiple factors to the photochemical reaction was obtained using the dimensionless data processing method. The mathematical model can help to carry out the coordinated selection of various parameters of photochemical reactions, reduce the reaction cost, and improve the reaction efficiency. Furthermore, we demonstrate the simplicity and accuracy of this reactor in measuring and calculating the quantum efficiency of photochemical reactions. This work is of great guidance to exploring the basic principles of photochemical reactions, the selection of reaction parameters, and the construction of photochemical reactors.
研究领域:
化学工程
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环境科学
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产品关联
DOI
高影响因子
Journal of Water Process Engineering
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2022
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IF 7.34
Bin Qi,Tiantian Chen,Zhifeng Liu,Jinqiu Qi,Qi Wang,Wenming Zhang,Xiaochen Li
To overcome the shortcomings of separation and recovery difficulties of powdered catalysts in practical applications, a novel flexible catalyst film (2D-WO 3 /CA) was formed by combining 2D-WO 3 with cellulose acetate (CA), and successfully applied in degrading organic pollutants in water under real solar irradiation. The structure, morphology and optical properties of the new photocatalytic film were characterized by using X-ray diffraction, scanning electron microscope and UV–vis diffuse reflectance spectra technology , respectively. The results showed that the absorption edges of 2D-WO 3 /CA film shifted remarkably to the longer wavelength compared with 2D-WO 3 , indicating that 2D-WO 3 /CA film could broaden the spectral response range. Furthermore, the photocatalytic capacity of the film was explored by degrading methylene blue (MB) in aquatic solution under real sunlight in the continuous baffled photo-reactor (CBPR). The film exhibited excellent degrading properties with an average removal rate of 85% for MB, and the processing load corresponded to 478.13 mg/(m 2 ·d). The film still had high activity and flexibility after treating wastewater for seven consecutive days. Therefore, the new 2D-WO 3 /CA film is promising in actual dye wastewater treatment . Based on the above analysis, MB degradation mechanism in the photocatalytic system with 2D-WO 3 /CA film was proposed finally.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Mingwei Shen,Guoqing Zhang,Jiayou Liu,Yuhang Liu,Jiayuan Zhai,Haochuan Zhang,Hesheng Yu
Photocatalysis has been widely employed as a promising method for wastewater treatment. However, existing studies are primarily conducted in batch reactors. To the best of our knowledge, a continuous reactor has not been used to degrade xanthate residual in mineral beneficiation wastewater. In this work, a continuous fixed-bed photoreactor (CFPR) was first designed, and Bi 2 WO 6 photocatalysts coated on silica sands were used to degrade sodium isobutyl xanthate (SIBX) under visible light irradiation. The effects of various parameters, including catalyst loading, pH level, initial SIBX concentration, wastewater flow rate, calcium ion (Ca 2+ ) concentration, magnesium ion (Mg 2+ ) concentration, and zinc ions (Zn 2+ ), on the degradation efficiency, were systematically investigated. The results show that the photodegradation percentage of SIBX increases with increasing catalyst loading, decreasing initial concentration, and decreasing flow rate within the scope under investigation. Additionally, low concentrations (30 mg·L −1 ) of Ca 2+ and Mg 2+ ions favor the photodegradation of SIBX, whereas excessive Ca 2+ and Mg 2+ ions (240 mg·L −1 ) inhibit photocatalytic activity. The presence of Zn 2+ ions inhibits photodegradation percentage. Furthermore, the photodegradation percentage is slightly higher at alkaline than at acidic pH. The maximum degradation percentage reached 95.40 % after 70 min of visible light irradiation under optimal conditions. In addition, a fixed bed reactor model considering surface reaction kinetics and mass transfer constraints was established by combining the Langmuir-Hinshelwood (L-H) kinetic equations and the series resistance theory. This model can accurately estimate the intrinsic kinetic parameters and can well predict degradation efficiency with a root-mean-square-error (RMSE) of 4.24 %. Finally, the bottleneck for improving the performance of the reactor can be identified under different conditions.
研究领域:
环境科学
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化学工程
·
材料科学
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产品关联
DOI
高影响因子
EUROPEAN POLYMER JOURNAL
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2023
·
IF 6
Huicai Zheng,Guichuan Xu,Wen Li,Xiaoju Zhang,Binshen Wang,Li Qin,Limei Zhou
Here we report a strategy to synthesize efficient polymeric carbon nitrides/3D honeycomb poly(ionic liquid)s photoreactor. The initial parent polymeric carbon nitrides (PCN) were synthesized by sintering precursor formed by self-assembling molecules of cyanuric acid and melamine. Ionic liquids with polymerizable groups polymerized in situ with crosslinkers in a system dispersed in PCN to synthesize a photoreactor. Impressively, the obtained photoreactors have structurally stable nanoparticle morphology in a dry state and a transparent 3D network structure in a swelling state. Their successful formation, swelling ability and morphology were fully characterized by XRD, WAXS, FT-IR, SEM, XPS, TEM and N 2 adsorption/desorption isotherm. UV–vis DRS, PL spectra, and photocurrent tests showed the improved photo-electric property of the photoreactor, which was attributed to the 3D network honeycomb structure improving the contact between the active centres in the reactor and the reaction substrate and the improving electron-hole separation efficiency of PCN by excellent electron transfer ability of poly(ionic liquid)s. These synthesized photoreactors could highly efficiently degrade the anionic dyes, such as methyl orange and acid blue 93, under a metal halide lamp or even natural sunlight.
研究领域:
材料科学
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环境工程
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光化学
·
纳米技术
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）