Synthesis and characterization of hybrid activated bentonite/alginate composite to improve its effective elimination of dyes stuff from wastewater

The current paper is paying attention to the synthesis of a low-cost, abundant and efficient hybrid activated bentonite–alginate composite ABent/A. Hybrid composite morphology was determined through FTIR, XRPD, and pHPZC. The operational conditions for the retention of two dyes used in the textile industry (methylene blue and crystal violet) from aqueous mediums were evaluated. Results showed that MB and CV adsorbed amount on ABent/A was 780 and 546 mg/g, respectively. Kinetic Lagergren’s and Ho and McKay’s models provide the best result for the MB and CV adsorption on the prepared adsorbent, respectively. Langmuir isotherm model gives the best analyses of the experimentation, justifying a monolayer and a homogeneous nature of adsorption process. Results indicate also that the operational conditions studied affect significantly dyes removal. Reusability study of ABent/A for dyes was also investigated according to the type of desorbing agents. MB regeneration was found 98.92% using hydrochloric acid 0.01 M and CV regeneration percent was 95% using 0.5 M potassium chloride prepared in the mixture ethanol/water (0.5%/0.5%). From the obtained results, hybrid activated bentonite/alginate composites are low-cost, effective and regenerable adsorbent, which give a promising prospect for contaminated wastewaters treatment.