Tailored nano clay blends for enhanced dye mixture adsorption in wastewater treatment

Abstract

Natural clays are eco-friendly, cost-effective, and industrially acceptable adsorbents employed in wastewater treatment. Textile effluents contains mixture of dyes where a single adsorbent often fails to treat completely. Herein, the simplest strategy for the efficient treatment of effluent with multicomponent pollutants using an tailored blend of two clay minerals has been presented. This strategy was studied using a binary blend of halloysite and montmorillonite clays (HAMT) to remove a mixture of industrial dyes, reactive Black-B (BB) and methyl red (MR) from the model effluent. Here, halloysite (HA) and montmorillonite (MT) selectively adorbs reactive black-B and methyl red respectively and could not completely treat model effluent individually whereas HAMT blend proved to be most effective. HAMT blend was prepared by convenient ultra-sonication assisted solution process and characterized using the various analytical techniques such as FT-IR, DR-UV spectra, XRD and SEM to determine structural, morphological features. Adsorption of model effluent studied as a function of pH, time, adsorbent loading and adsorbate concentration. The dye removal efficiency was remarkably enhanced when the HAMT blend was used according to the concentration of dyes present in the model effluent. The maximum dye removal efficiency was attained using HAMT (1:1) blend for effluent with an equimolar concentration of selected dyes. Similarly, HAMT (2:1) found suitable for the treatment of real textile effluent collected from local textile industries based on its assessment. This study aids in the development of a tailored adsorbent blend using conventional adsorbents for complex effluent treatment in a cost-effective way, eliminating the need for specialized materials.