Preparation and evaluation of celite decorated iron nanoparticles for the sequestration performance of hexavalent...

The increasing usage of an important heavy metal chromium for industrial purposes, such as metallurgy, electroplating, leather tanning, and other fields, has contributed to an augmented level of hexavalent chromium (Cr(VI)) in watercourses negatively impacting the ecosystems and significantly making Cr(VI) pollution a serious environmental issue. In this regard, iron nanoparticles exhibited great reactivity in remediation of Cr(VI)-polluted waters and soils, but, the persistence and dispersion of the raw iron should be improved. Herein, this article utilized an environment-friendly celite as a modifying reagent and described the preparation of a novel composites namaly celite decorated iron nanoparticles (C-Fe⁰) and evaluation of C-Fe⁰ for the sequestration performance of Cr(VI) from aqueous solution. The results indicated that initial Cr(VI) concentration, adsorbent dosage, and especially solution pH are all critical factors to control C-Fe⁰ performance in Cr(VI) sequestration. We demonstrated that C-Fe⁰ could achieve a high Cr(VI) sequestration efficiency with an optimized adsorbent dosage. Fitness of the pseudo-second-order kinetics model with data indicated that adsorption was the rate-controlling step and chemical interaction controlled Cr(VI) sequestration on C-Fe⁰. The adsorption isotherm of Cr(VI) could be the best depicted by Langmuir model with a monolayer adsorption. The underlying sequestration path of Cr(VI) by C-Fe⁰ was then put forward, and the combined effect of adsorption and reduction implied the potentials of C-Fe⁰ in Cr(VI) removal.