“…Adsorption is considered as the most promising method due to its high efficiency, easy to operate, economical, renewable, and technological feasibility. 20,21 Numerous adsorbents including silica gel, 10,22 various types of nanomaterials, [23][24][25] nanobers, 19,26 biochar, 20,27 hydrogel, 28 functionalized polymers, 8,29 metal composite 30 and metal-organic frameworks 31 have been used for Cr(VI) removal.…”