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《环境科学学报(英文版)》2023,35(4):249-262
AgCl/ZnO/g-C3N4, a visible light activated ternary composite catalyst, was prepared by combining calcination, hydrothermal reaction and in-situ deposition processes to treat/photocatalyse tetracycline hydrochloride (TC-HCl) from pharmaceutical wastewater under visible light. The morphological, structural, electrical, and optical features of the novel photocatalyst were characterized using scanning electron microscopy (SEM), UV-visible light absorption spectrum (UV–Vis DRS), X-ray diffractometer (XRD), Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), and transient photocurrent techniques. All analyses confirmed that the formation of heterojunctions between AgCl/ZnO and g-C3N4 significantly increase electron-hole transfer and separation compared to pure ZnO and g-C3N4. Thus, AgCl/ZnO/g-C3N4 could exhibit superior photocatalytic activity during TC-HCl assays (over 90% removal) under visible light irradiation. The composite could maintain its photocatalytic stability even after four consecutive reaction cycles. Hydrogen peroxide (H2O2) and superoxide radical (·O2) contributed more than holes (h+) and hydroxyl radicals (·OH) to the degradation process as showed by trapping experiments. Liquid chromatograph-mass spectrometer (LC-MS) was used for the representation of the TC-HCl potential degradation pathway. The applicability and the treatment potential of AgCl/ZnO/g-C3N4 against actual pharmaceutical wastewater showed that the composite can achieve removal efficiencies of 81.7%, 71.4% and 69.0% for TC-HCl, chemical oxygen demand (COD) and total organic carbon (TOC) respectively. AgCl/ZnO/g-C3N4 can be a prospective key photocatalyst in the field of degradation of persistent, hardly-degradable pollutants, from industrial wastewater and not only. 相似文献
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TiO2/ZnO光催化降解四环素的研究 总被引:11,自引:0,他引:11
以太阳光、汞灯为光源,TiO2/ZnO复合半导体为催化剂处理四环素溶液,探讨了催化剂的配比、溶液体积、光照时间、pH、初始浓度、光强等6种因素对光催化活性的影响,比较了汞灯和太阳光作光源时的光催化效果,结果表明,用太阳光作光源时光催化效果也较好。 相似文献
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The adsorption of antibiotic tetracycline onto silica particles was investigated. The effects of pH, electrolyte concentration
and temperature on the adsorption equilibrium were examined and the data correlated with a dual site adsorption model. Adsorption
of tetracycline onto approximately 9% of the adsorption sites was found to be irreversible, whereas the rest exhibited Langmuir
behaviour. Increasing pH of the solution had a strong negative effect on the adsorbed amounts. Adsorption decreased also with
increasing ionic strength and temperature. The enthalpy and entropy of adsorption were found to be approximately −16 and −25 J/mol,
respectively. 相似文献
15.
四环素工业废水生化处理工艺的研究 总被引:6,自引:0,他引:6
本文报道了四环素生产废水絮凝处理的最佳组合是15mg/kg聚丙烯酰胺+3000mg/kg硫酸亚铁;经驯化的接种水测出COD为2764mg/L时,废水的BOD5为1873mg/L,BOD5/COD≈68%,属易生化处理范畴。生物膜处理可在2d内将COD从4488mg/L降至549mg/L,处理中的优势菌群为G^+芽孢杆菌。经γ射线辐射后,废水对细菌不再有抑制作用。 相似文献
16.
Maghemite (ϒ-Fe2O3) nanoparticles were impregnated to nanoporous carbon obtained from tomato waste (TWNC). The prepared magnetic composite (MTWNC) was characterized and used to remove tetracycline (TC) from water and then easily be separated from the medium by a magnetic technique. The morphologies and surface chemistries of both magnetic and non-magnetic nanoporous carbons were studied by FTIR, XRD, SEM, SEM-EDX, VSM, BET surface area, proximate and elemental analysis determinations. Batch adsorption studies were carried out and the effects of pH, initial TC concentration, adsorbent dose, ionic strength and temperature were investigated. The adsorption kinetics of TC on MTWNC could be expressed well by the pseudo-second order model, and sorption isotherms were described by Langmuir equation with maximum adsorption capacity of 60.60 mg/g at pH 4 and 50 °C. Thermodynamic parameters showed that the adsorption of TC onto MTWNC was feasible, spontaneous and endothermic. Furthermore, the recyclability of the adsorbent was tested with 0.01 M NaOH solution, and the results show that the synthesized composite adsorbent could be employed repeatedly in wastewater treatment. 相似文献
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Yaqian Shen Ke Zhu Dongdong He Jin Huang Hongmei He Lele Lei Wenjin Chen 《环境科学学报(英文版)》2022,34(1):351-366
Recently, metal-based carbon materials have been verified to be an effective persulfate activator, but secondary pollution caused by metal leaching is inevitable. Hence, a green metalfree 3D macroscopic N-doped porous carbon nanosheets(NPCN) was synthesized successfully. The obtained NPCN showed high adsorption capacity of tetracycline(TC) and excellent persulfate(PS) activation ability, especially when calcined at 700 °C(NPCN-700). The maximum adsorption capacity of NPCN-700 was 121.51 mg/g by ... 相似文献
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The occurrence of antibiotics in the environment has recently raised serious concern regarding their potential threat to aquatic ecosystem and human health. In this study, the magnetic ion exchange(MIEX) resin was applied for removing three commonly-used antibiotics, sulfamethoxazole(SMX), tetracycline(TCN) and amoxicillin(AMX) from water.The results of batch experiments show that the maximum adsorption capacities on the MIEX resin for SMX, TCN and AMX were 789.32, 443.18 and 155.15 μg/m L at 25°C,respectively, which were 2–7 times that for the powdered activated carbon. The adsorption kinetics of antibiotics on the MIEX resin could be simulated by the pseudo-second-order model(R~2= 0.99), and the adsorption isotherm data were well described by the Langmuir model(R~2= 0.97). Solution p H exhibited a remarkable impact on the adsorption process and the absorbed concentrations of the tested antibiotics were obtained around the neutral p H.The MIEX resin could be easily regenerated by 2 mol/L Na Cl solution and maintained high adsorption removal for the tested antibiotics after regeneration. Anion exchange mechanism mainly controlled the adsorption of antibiotic and the formation of hydrogen binding between the antibiotic and resin can also result in the increase of adsorption capacity. The high adsorption capacity, fast adsorption rate and prominent reusability make the MIEX resin a potential adsorbent in the application for removing antibiotics from water. 相似文献
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陈秋兰 《环境监测管理与技术》2019,31(3):49-52
沉积物样品用乙腈-柠檬酸缓冲溶液提取后经HLB-SPE柱净化,采用LC-MS/MS法在MRM模式下测定17种磺胺类和4种四环素类抗生素,通过优化测定条件,使方法在0. 500μg/kg~100μg/kg范围内线性良好。方法检出限为0. 15μg/kg~1. 2μg/kg,2个质量比水平的加标回收率为44. 1%~125%,试验5次结果的RSD 16. 0%。将该方法用于测定厦门近岸海域沉积物中抗生素,共有6种磺胺类和4种四环素类抗生素检出,测定值为0. 3μg/kg~26. 2μg/kg。 相似文献
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DNA damage and changes in enzyme activities were used as biomarkers to evaluate the genotoxicity and oxidative stress of tetracycline and chlortetracycline on the earthworm Eisenia fetida. The results showed that both antibiotics induced significant genotoxicity on earthworms in a dose-dependent manner (p < 0.01) with chlortetracycline having a stronger effect than tetracycline in the short term. The tests on the activities of superoxide dismutase (SOD) and catalase (CAT) enzymes further indicated biochemical stresses induced by the antibiotics. An N-shaped activity pattern was noted with the enzyme activities being stimulated first, then inhibited, and stimulated again with increasing concentration. The induced activity of SOD or CAT could scavenge oxygen free radicals and protect the organisms against oxidative stress by alleviating the corresponding DNA damage. Compared to enzyme activities, DNA damage as a biomarker was more sensitive and is thus more suitable for detecting low concentration exposure and diagnosing the genotoxicity of contaminants in terrestrial environment. 相似文献