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Silica-Magnetite Composite as an Eco-Friendly Adsorbent for Aqueous Tetracycline Removal – Kinetic and Isotherm Studies

Karina Sofyatuddin, Perdana Adli Waliul, Prajaputra Vicky, Isnaini Nadia, Nuufus Putri Hayyatun, Bismi Audia

Ecological Engineering & Environmental Technology

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2024

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Vol. 25, iss. 1

82--92

EN

Silica and magnetite have been recognized as emerging and effective environmentally-friendly pollutant removers. In this study, the effectiveness of silica/magnetite (SM) composites derived from local beach sand were developed and evaluated as an environmentally friendly adsorbent for taking up tetracycline from water. The formation of SM composites was verified through characterization performed using Fourier-transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), and Scanning Electron Microscope (SEM) analysis. Two key parameters, kinetics and isotherms, were investigated to find the best condition for tetracycline adsorption using SM composites. In the kinetic adsorption studies, the pseudo-first-order, with correlation coefficients (R2 > 0.99) higher than those of the pseudo-second-order and Elovich models, was performed to be the best-fitting model due to the close alignment between the experimental and theoretical data. The non-linear Langmuir isotherm model offered the most accurate fit (R2 = 0.954, root-mean-square-errors = 1.505) compared to the Freundlich model, signifying that the adsorption process takes place on a uniform surface where the adsorbate is distributed in monolayers. In the present study, the maximum adsorption capacity of tetracycline onto SM composite reached 29.955±4.165 mg/g for 24-hour contact time with an adsorption rate constant of 0.415±0.050 min-1. In conclusion, the developed environmentally conscious composite demonstrates the potential to be an effective adsorbent with remarkable tetracycline removal properties while also providing valuable insights for further research.

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Effect of Mn(II) on tetracycline degradation by a selected strain Burkholderia sp.

Jiao Chaoxing, Xiong Hongbin, Zhou Benjun

Ecological Chemistry and Engineering. S

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2023

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Vol. 30, nr 3

417--427

EN

Removal of residual tetracycline (TC) in the environment is an important issue for pollution control. In this study, a TC-degrading strain named JX_1 was isolated from the soil around an industrial park, the strain was identified as Burkholderia sp. by 16s rDNA sequencing analysis. The effects of various factors on TC degradation by the strain were studied, results indicated that the inoculation amounts and liquid volume had little effect on TC degradation rate. However, the degradation rate of TC by strain increased with the increase of pH, and the residual concentration increased gradually with the initial TC concentration increased. The degradation rate of 125 mg/L TC by strain JX_1 was 75.76 % under the conditions of temperature 37 °C, 2 mL inoculation amount and 200 mL liquid volume. Under the same conditions, the degradation rate of TC was increased to 91.39 % with the addition of 0.75 g/L MnSO4, indicating that Mn(II) could improve the degradation rate of TC by strain JX_1 to a certain extent.

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Tetracycline removal from water by adsorption on geomaterial, activated carbon and clay adsorbents

Ait-Hamoudi Souhila, Hamdi Boualem, Brendlé Jocelyne

Ecological Chemistry and Engineering. S

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2021

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Vol. 28, nr 3

303--328

EN

The use of antibiotics for breeding and for humans increased considerably in recent years, as a dietary supplement to enhance animal growth. This frequent use leads to the detection of residues in water and wastewater. Thus, the emergence of new strains of bacteria resistant to these antibiotics and, can lead to incurable diseases of livestock, and can lead to a possible transmission of these strains to humans. The purpose of this work is to develop new materials based on treated Maghnia clay, activated carbon, cement, and PVA polymer, named geomaterials. These materials were intended for the containment of hazardous wastes in landfills. The removal of tetracycline from aqueous solution was tested by adsorption onto synthesised geomaterials and their mineral constituents. Adsorption kinetics revealed that tetracycline was rapidly retained by GM and ATMa. This was confirmed by the relatively short equilibrium time of 30 min. The pseudo-second-order and intraparticle models well fitted the adsorption kinetic of the TC-adsorbent studied systems. It was noticed that the adsorption kinetic passes through several mechanisms, was demonstrated by the multi-linearity on the plot of qt against the square root of t. The adsorption capacity (Qa) of TC onto GM is pH-dependent. Indeed, Qa reaches a maximum value (Qa = 12.58 mg · g–1 at a very acidic pH of 2, then the adsorbed amount decreases to reach a minimum value at pH of 8, and for basic pHsQa increases up to 10 mg · g–1.