emoval of malachite green dye from aqueous solutions by diasporic Greek raw bauxite

Abstract

Raw bauxite from Klisoura mine (Prefecture of Fokida, Greece) containing 72 wt.% diaspore, 16 wt.% hematite, 6 wt.% quartz, 4 wt.% anatase and 2 wt.% calcite, has been used for the removal of malachite green dye from aqueous solutions. The batch type experiments were conducted with 10 ml of solution, at pH = pHZPC = 6.7 and contact time 1 h. The initial concentration of malachite green dye was 10 mg/l, the bauxite quantity was 0.02 g, 0.04 g, 0.06 g, 0.1 g and 0.2 g. The highest adsorption capacity achieved was 4.5 mg/g (90% removal) using 0.02 g bauxite. The removal capacity of raw bauxite is comparable to other non-conventional adsorbents, such as neem sawdust, sugar cane dust and cane root carbon.

Cetyltrimethylammonium Bromide (CTAB) Bloated Micelles and Merged CTAB/Bolaamphiphiles Self-Assembled Vesicles toward the Generation of Highly Porous Alumina as Efficacious Inorganic Adsorbents

“…78−82 In aqueous solutions with pH less than pHzpc, surface hydroxyl groups of alumina exist in the form of Al− + OH 2 as a result of protonation reaction. 78,82 So, at pH < pHzpc, the surfaces of the HiPA-CT and HiPA-CT-10 were positively charged, while at pH values above 10, because of the deprotonation of surface hydroxyl groups of alumina and forming of Al−O − species, the HiPA-CT and HiPA-CT-10 were in anionic forms. Additionally, CIP molecules exist as cation, zwitterionic, and anion species in aqueous solutions with pH ranges below 5.8, between 5.8 and 8.9, and above 8.9, respectively.…”