Bioremediation of malachite green dye using sodium alginate, Sargassum latifolium extract, and their silver nanoparticles

INTRODUCTION: The textile, paper, rubber, plastic, leather, cosmetics, pharmaceutical, and food sectors extensively use malachite green (MG). In spite of this, it has mutagenic, carcinogenic, teratogenic, and, in some circumstances causes chronic respiratory disease. OBJECTIVES: In this work, we used sodium alginate, Sargassum latifolium aqueous extract, and their silver nanoparticles to test their potential as inexpensive adsorbent agents to remove malachite green dye from aqueous solutions. METHODS: The removal rate of MG was determined using a series of bioadsorption experiments. Besides, the effect of different factors on bioadsorption, such as pH, adsorbent dose, contact time (min), and different concentrations of MG dye was investigated. RESULTS: The removal efficiency of MG dye by alginate nanoparticles, alginate, Sargassum latifolium aqueous extract, and S. latifolium aqueous extract nanoparticles was 91, 82, 84, and 68 respectively. The optimal conditions for bioadsorption of malachite green dye were pH 7, a contact time of 180 min, and an adsorbent dose of 0.02 g. The adsorption isotherm was fitted to Langmuir and Freundlich isotherm. Also, UV and FT–IR before and after the bioadsorption of MG were performed to confirm the bioadsorption process. CONCLUSION: Our results indicated that alginate nanoparticles were the most effective bioadsorbent agent.