CHEMICAL ENGINEERING JOURNAL
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2013
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IF 3.473
Changwang Shao,Guowei Zhou,Zhaocheng Li,Yue Wu,Delan Xu,Bin Sun
Large-diameter tube-like mesoporous TiO 2 nanotubes were synthesized via homogeneous precipitation from aqueous solutions containing titanium oxysulfate (TiOSO 4 ) using urea. The cationic surfactant cetyltrimethylammonium bromide was used as a structure-directing agent. Prepared samples were characterized by X-ray diffraction, transmission electron microscopy (TEM), field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, and N 2 adsorption–desorption isotherms. Experimental results indicated that the samples exhibit tube-like structures with lengths of approximately 6 μm to 8 μm, large tube diameters of approximately 500 nm to 600 nm, and a wall thickness of approximately 450 nm. TEM images and N 2 adsorption–desorption isotherms showed that the tube walls of the samples have a uniform mesoporous structure. A possible mechanism for the formation of tube-like mesoporous TiO 2 was proposed. The photocatalytic activities of the large-diameter tube-like mesoporous TiO 2 were assessed via the photocatalytic decomposition of papermaking wastewater under ultraviolet light irradiation. The effects of different parameters such as UV light irradiation, catalyst dosage and solution pH on photocatalytic activities of tube-like mesoporous TiO 2 were studied. The as-synthesized tube-like TiO 2 showed higher photocatalytic activities than Degussa P25. MTS3 exhibited the highest photocatalytic activity. The chemical oxygen demand and chroma percent degradations of papermaking wastewater were approximately 73.0% and 99.5%, respectively, at MTS3 dosage of 1.0 g/L and pH value of 3.0 after 12 h of photodegradation.
研究领域:
材料科学
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环境科学
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产品关联
DOI
高影响因子
WATER AIR AND SOIL POLLUTION
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2020
·Vol. 231
·期 8
·1-14
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IF 1.9
Zhao Tianyu,Cheng Hao,Liang Yinna,Xiong Jianhua,Zhu Hongxiang,Wang Shuangfei,Liang Jiaxiang,Chen Guoning
Photocatalysis has emerged as a promising approach for treating environmental pollution. In this study, TiO 2 /sponge composites with good photocatalytic activity in visible light were prepared via a simple and efficient low-temperature process and applied to the degradation of 2,4,6-trichlorophenol (2,4,6-TCP) present in papermaking wastewater. The process conditions for preparing TiO 2 /sponge composites were optimized by varying the TiO 2 dosage, cellulose dosage, and surfactant concentration. Scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) results showed that TiO 2 successfully adhered to the sponge surface and that the composites achieved a good recycling effect. Degradation occurred under visible light, and a degradation rate of 81% for 2,4,6-TCP with initial concentration of 20 mg/L was achieved in 4 h. The fragments were analyzed using ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS), which revealed the formation of 2-hydroxyvaleric acid (2-HVA) as a degradation product; a possible degradation mechanism is proposed to interpret these findings. Visible-light photocatalysis shows high potential for the rapid and environmentally friendly destruction of organic pollutants in papermaking wastewater.
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
FIBERS AND POLYMERS
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2021
·Vol. 22
·期 6
·1518-1525
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IF 2.153
Chen Chaoying,Zhang Xiumei,Deb Hridam,Liang Fugen,Zhu Haidong,Cui Kecong,Zhang Yong,Yao Juming
Flocculation is the first and important step to remove suspended and slightly soluble pollutants in industrial wastewater treatment. Flocculant is just the key element for flocculation process. Polyacrylamide (PAM) is the most widely used flocculant. But it still holds some potential flaws which are ignored by people. An eco-friendly bamboo cellulose-grafted-ployacrylamide flocculant (BC-g-PAM) was then synthesized by free-radical graft copolymerization in homogeneous aqueous solution. The optimal synthesis conditions of the BC-g-PAM was investigated. FTIR, TG, XRD and FESEM were employed to characterize and define its molecular structure and physical characteristics. The BC-g-PAM was also adopted to treat an actual papermaking wastewater. The positive results showed that the BC-g-PAM exhibited an excellent flocculation performance on the papermaking wastewater. The average turbidity removal rate reached 99.7 % and related suspended solids exhibited the corresponding decline. This flocculation also caused a positive effect on the reduction of COD Cr and BOD 5 of the wastewater. Meanwhile, the BC-g-PAM exhibited an excellent biodegradability. Its degradation rate reached 63.4 % at 90 d in soil extracting solution.
研究领域:
环境科学
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化学工程
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废水处理
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产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2023
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IF 5.2
Pengju Liu,Xu Yang,Weiwei Chen,Yi Hao
To solve the shortcomings of poor solubility, low cationic strength , and small molecular weight of chitosan (CTS), acryloyloxyethyl trimethyl ammonium chloride (DAC) and 2-acrylamido-2-methylpropanesulfonic acid (AMPS) were introduced into the amino group of chitosan by graft copolymerization , and the modified chitosan flocculant CTS-DAC-AMPS was successfully prepared. The performance of CTS-DAC-AMPS in the treatment of papermaking wastewater was investigated, and the mechanism of the flocculation process was analyzed. The results showed that the crystal habit of CTS-DAC-AMPS was reduced, and the solubility range was broadened compared with CTS due to the introduction of DAC and AMPS. In addition, CTS-DAC-AMPS with quaternary ammonium and sulfonic groups prompted its cationic strength stronger than CTS. In addition to high thermal stability, CTS-DAC-AMPS, composed of two CTS molecules, one DAC molecule, and one AMPS molecule, had a long molecular chain . The results of flocculation experiments showed that the performance of CTS-DAC-AMPS in treating papermaking wastewater was better than that of unmodified CTS and commercially available flocculants. Based on the experimental results, the mechanism of CTS-DAC-AMPS treatment of papermaking wastewater was mainly charge neutralization.
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
JOURNAL OF HAZARDOUS MATERIALS
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2022
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IF 14.224
Haoran Feng,Min Liu,Taotao Tang,Ye Du,Bing Yao,Chengyu Yang,Changjie Yuan,Ying Chen
The present study applied the ozonation process to degrade 2,4-di- tert -butylphenol (2,4-DTBP), an emerging micropollutant detected in typical bamboo pulp and papermaking wastewater (BPPW). The effects of various influencing factors on the degradation performance and corresponding degradation mechanism were investigated. The results showed that ozone could degrade 2,4-DTBP rapidly with a reaction rate constant of (1.80 ± 0.05) × 10 5 M –1 ·s –1 . The removal efficiency of 2,4-DTBP (5 mg/L) could reach 100% when the ozone dosage exceed 6 mg/L in a neutral medium. The presence of coexisting chemicals in BPPW such as Cl – and HCO 3 – promoted the removal performance of 2,4-DTBP. In contrast, NH 4 + and humic acid presented inhibition on 2,4-DTBP removal. The ozonation of 2,4-DTBP was dominated by the ozone molecule, and this was primarily attributed to electrophilic substitution and 1,3-dipolar cycloaddition reactions. Twenty-seven kinds of intermediate products were identified by UPLC-Q-TOF/MS. The variations in their productions were based on the changes in ozone dosage. The degradation pathways were proposed. The toxicity of 2,4-DTBP was weakened after ozonation. As for the ozonation of actual biochemical effluent of BPPW, the desirable treatment performance was obtained. This study proved the feasibility of ozonation and provided data basis for subsequent pilot study.
研究领域:
环境工程
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水处理
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化学工程
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污染物降解
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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）