Danial Nayeri; Seyyed Alireza Mousavi; Azadeh Mehrabi
Abstract
In this study, oxytetracycline removal from aqueous solution by activated carbon prepared using corn stalks has been investigated. The adsorbent was characterized using Fourier transform infrared spectrophotometer (FTIR) and scanning electron microscope (SEM). The effects of main variables; adsorbent ...
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In this study, oxytetracycline removal from aqueous solution by activated carbon prepared using corn stalks has been investigated. The adsorbent was characterized using Fourier transform infrared spectrophotometer (FTIR) and scanning electron microscope (SEM). The effects of main variables; adsorbent dose, contact time, pH, and initial oxytetracycline concentration on the efficiency of adsorption efficiency were investigated. Results confirmed the effects of main variables and the maximum removal of antibiotic (99.9 %) achieved at initial concentration of 10 mg/L, pH of 9, and contact time of 60 min, when adsorbent dose was 1.5 g. The results of isotherm and kinetic studies showed that the oxytetracycline adsorption onto activated carbon prepared from corn stalks follows Freundlich isotherm (R2 = 0.98) and pseudo-second order kinetic model (R2 = 0.99). The maximum adsorption capacity of oxytetracycline was 522.6 mg/g. In brief, the activated carbon that has been prepared from corn stalks as low cost, non-toxic and environment friendly adsorbent shows a good ability for removal of oxytetracycline form water and wastewater.
Yonus Yosofi; Ali Almasi; Seyyed Alireza Mousavi
Abstract
Oil refinery wastewater as the most polluting industrial wastewater contain various hydrocarbons and sulfur with its derivatives and can cause problems in biological systems by the production of sulfuric acid. Variations of amount of sulfur depending on bioreactor condition such as temperature, pH, microbial ...
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Oil refinery wastewater as the most polluting industrial wastewater contain various hydrocarbons and sulfur with its derivatives and can cause problems in biological systems by the production of sulfuric acid. Variations of amount of sulfur depending on bioreactor condition such as temperature, pH, microbial activity and other factors. This study focused on determining variations of sulfur in anaerobic ponds for treatment of oil refinery wastewater. Samples were taken every 6 days during eight consecutive months and the type of sampling was 24-hour composite. This means that each sample is composed of 12 samples in 24 hours. 40 samples were taken from inlet and outlet of anaerobic stabilization pond for measuring sulfate, sulfide and sulfur, so a total of 240 samples were analyzed in this study. The results of the study showed that removal efficiency of COD and BOD were obtained 43 % and 24 %, respectively. Variations of sulfide and sulfur were obtained 4 % and 44 %, which increase respectively, but for sulfate have shown 15.8 % reduction. It can be said that sulfate-reducing bacteria have had significant activity to produce sulfide and sulfur form and decrease of the amount of sulfate in bioreactor.
