Co-polymerization of RAFT agents on magnetic nanoparticles for efficient selective removal of Alizarine Reds dyes from water

Alizarin Red S is one of the anionic dyes that categorized as an anthraquinone dyes and broadly applied in textile industry. It is known as a carcinogenic substance and also due to its thermal, optical and physicochemical stability it is considered to be highly dangerous and durable pollutants [1]. According to the literature, among numerous chemical and physical processes that have been adopted for dye removal and purification of wastewater, adsorption technique is more favorable, useful and efficient approach due to its easy handling and economic feasibility [1]. Presently, magnetic nanoparticle-based adsorbent are emerged as a promising and popular materials because of their valuable features including large surface area, simplicity of synthesis procedures, easy surface functionalization with organic/inorganic groups, and etc. [2]. The present study was established to analyze the capability of Alizarin Red S dye adsorption onto RAFT surface modified magnetic nanoparticles. The effect of process parameters such as adsorbent dosage, pH, contact time and initial concentration on dye adsorption were studied on the performance of dye removal. The results showed that the removal percent of ARS reached from 72% to 93% by increasing adsorbent dosage. Maximum dye removal was observed at pH 7, therefore; neutral pH was chosen to conduct the following experiments. The isotherms such as Langmuir and Freundlich were examined and the Langmuir isotherm model gives the best fit with the highest R2 value ( 0.99) compared to the other model. The obtained results indicated that the proposed modified magnetic nanoparticles were shown to be a promising adsorbent for the removal of dyes from several aqueous solutions.