Adsorption of the reactive azo dyes onto NH[4]Cl-induced activated carbon

Background: The efficacy of NH[4] Cl-induced activated carbon [NAC] was examined in order to adsorb RR198, an azo reactive model dye, from an aqueous solution

Methods: The effects of pH [3 to 10], adsorbent dose [0.1 to 1.2 g/L], dye concentration and contact time on the adsorption efficiency were investigated

Results: The results showed that the removal of dye was highest at a solution pH of 7 and a powder dose of 1.1 g/L. The 85.9%, 72.6% and 65.4% removal of RR198 was obtained for a concentration of 25, 50 and 100 mg/L, respectively, at a relatively short contact time of 30 minutes, and at optimum pH and NAC concentrations of 1 g/L. The experimental data for kinetic analysis illustrated a best fit to the pseudo-second-order model. The study data on equilibrium were modeled using Langmuir, Freundlich and Dubinin-Radushkevich models; the Langmuir equation provided the best fit for the data

Conclusion: Therefore, the NAC appears to be an efficient and appropriate adsorbent for the removal of reactive azo dyes from waste streams

Adsorption potential of the granular activated carbon for the removal of amoxicillin from water

Background: Antibiotics are important pollutants of water resources, and because of hard biodegradability, they can be filtered through adsorption method. Activated carbon is one of the best adsorbents. The aim of this study was to investigate the amoxicillin removal rate of a standard granular activated carbon

Materials and methods: The adsorption experiments were conducted in the stirred [100 rpm] glass reactor. In each test, 50 ml of aqueous solution contaminated by amoxicillin was transferred into the reactor, and the influence of adsorbent dose, adsorbent type, amoxicillin concentration, reaction time, solution pH and temperature was tested on the amoxicillin adsorption. At the end of each of adsorption tests, the suspension was filtered using a cellulose acetate filter with 0.45?m pore size and the filtrate was analyzed for residual amoxicillin using HPLC

Results: The obtained data showed that the best conditions for removal of amoxicillin from contaminated water using granular activated carbon were as follow: pH: 6, adsorbent concentration: 1.6 g/l, reaction time: 60 min, temperature: 25oc. In these conditions up to 86% of amoxicillin [concentration: 50 mg/l] could be adsorb by a granular 16-20 activated carbon

Conclusion: Adsorption onto activated carbon is an efficient method for the removal of non-degradable water pollutants such as antibiotics and toxins