Evaluation of Synthesized Fe3O4/MWCNTs Nanocomposite Used in the Heterogeneous Fenton Process for the Removal of Ciprofloxacin Antibiotic

Ciprofloxacin is an antibiotic vastly administrered for the treatment of infections. A major paortion of the drug remains non-metabolized and is excreted to find its way ultimately into water environments through discharge into wastewater. Although carbon nanotubes have been widely employed for the removal of contaminants, ciprofloxacin still poses problems against its proper removal. It is the objective of the present study to synthesize magnetite Fe3O4/MWCNTs and to evaluate its performance in ciprofloxacin removal via the heterogeneous Fenton process. For this purpose, the performance of the synthesized nanocomposite was evaluated while the effects of the following parameters were also investigated on the heterogenous Fenton process under lab conditions: pH, 4‒10); adsorbent quantity, 1‒3 g/l; initial antibiotic concentration, 30‒200 mg/l; contact time, 15‒300 min; and H2O2 concentration, 5‒25 μmol/l. Moreover, the synthesized Fe3O4/MWCNTs  was morphologically and microstructurally characterized using Transmission Electron Microscopy (TEM) and X-ray diffraction (XRD) while the formation of carboxylic functional groups was verified by Fourier transform infrared spectra (FT-IR). It was found that the efficiency of the heterogeneous Fenton process for the removal of ciprofloxacin at a concentration of 30 mg/l was 95% in approximately 180 minutes and a molar ratio of 1 ml H2O2/2g Fe. Based on the results obtained, the Fe3O4/MWCNTs magnetite nanocomposite is well capable of removing ciprofloxacin from aqueous solutions in the heterogeneous Fenton process

Efficiency Comparison of Modified-Clay and Lime-Marlin the Adsorption of Fluoride from Aqueous Solution

Background and purpose: Fluoride is one of the common anion in water that its concentration varies in different water supplies. Most of the body's requirement for fluoride is supplied through drinking water. Fluoride in low concentration is essential for human health but in high concentration is very hazardous for human health. The efficiency of modified-clay and lime-marl were investigated in this research as an adsorbent for the elimination of fluoride from aqueou solution.  Methods: In this study, the capability of modified-clay and lime-marl to adsorb fluoride ions was conducted using a series of batch tests in a shaker-incubator instrument. The effect of experimental parameters such as pH (4,7,10),  adsorbent dosage (1,5,10 g/L), initial fluoride concentration  (5,10,15 mg/L) andcontact time (15-120 min) were evaluated. The morphological and micro-structural character of  modified-clay and lime-marl have performed by using X-ray diffraction (XRD). The formation of the carboxylic functional groups was verified by Fourier transform infrared spectra (FT-IR).  Findings: results well demonstrate higher removal efficiency of fluoride was 95.23% and 28.71 by clay-modified and lime-marl, respectively; at 10 mg/L of fluoride concentration and 60 min contact time. The adsorption kinetics fitted well using the pseudo second-order kinetic model; however, equlibrium data were best fitted onto Langmiur isotherm model. The maximum adsorption capacities of modified-clay and lime-marl for fluoride were found to be 4.43 mg/g and 1.32 mg/g, respectively. Conclusion: According to our finding, it proposed that adsorption process by using modified clay is very efficient and economic process for fluoride removal from aqueous solution

Investigation of Phenol Removal from Aqueous Solutions by Electrofenton and Electropersulfate Processes

Phenol, or benzene hydroxyl is a toxic aromatic hydrocarbon discharged into the environment through certian industrial effluents which, thereby, pollute water resources. This study examines phenol removal from aqueous solutions through electro-Fenton and electro/persulfate processes using iron electrodes. For this purpose, a laboratory-scale electrochemical batch reactor was used that was equipped with four electrodes and a direct DC power supply. In the tests carried out, the effects of operational parameters such as initial pH; current density; and initial concentrations of phenol, hydrogen peroxide, and persulfate on the removal of phenol were investigated. The results showed that EPS and EF processes achieved phenol removal efficiencies of 95.18% and 93.99%, respectively, at operating conditions of pH = 3, initial phenol concentration of 100 mg/l, hydrogen peroxide and persulfate concentration of 0. 4 mM, and a current density 0.07A/dm2 over 45 min. Increasing persulfate and hydrogen peroxide concentration from 0.4 to 0.8 mM reduced phenol removal efficiencies from 95.18% and 93.99% to 43% and 85%, respectively. Generally speaking, EPS and EF processes exhibited almost identical phenol removal efficiencies. Finally, the integrated electrochemical and persulphate process was found to be more productive in producing electrical iron and persulphate activation than using each single process in isolation