Adsorption of Zn²⁺ from solutions on manganese oxide obtained via ozone precipitation reaction

Abstract

Synthesis via ozone precipitation reaction was used to obtain manganese dioxide (OMD) and it was probed as an adsorbent for zinc ions. Adsorption was followed along shaking time and increasing ratio ] / [Zn 2+ ], and isotherms were obtained at different pH values and in the presence of several anions (chloride, nitrate, sulphate, and acetate). It was found that adsorption equilibrium is fast and follows the pseudo-second order model (q e = 34 ±1 mg/g and K = 0.07 ±0.01 g/mg h). Isotherms were fi tted to Langmuir, Freundlich, and LangmuirFreundlich models, and the best fi tting was found with the last one. The process is dependent on pH and the effi ciency increases from pH 1 to 4. The ratio [NO 3 -] / [Zn 2+ ] up to 3 does not seem to change the behaviour of the process. Regarding the anions, the effi ciency of Zn(II) adsorption occurs according to: acetate > nitrate and sulphate > chloride. Manganese oxide obtained via ozonization is an excellent adsorbent for zinc ions.

Preparation and Characterization of a Novel Amidoxime-Modified Polyacrylonitrile/Fly Ash Composite Adsorbent and Its Application to Metal Wastewater Treatment

“…Zinc is an important trace element in the human body and one of the heavy metal elements harmful to nature [ 1 , 2 , 3 ]. The harm of zinc to the human body mainly comes from the accumulation of industrial wastewater in water and organisms, which is a potential threat to human health through the food chain [ 4 , 5 , 6 ].…”

Synthesis of MnO2 on Activated Carbon and its Potential Application in the Adsorption of As(V) and Pb(II) in Aqueous Solutions

“…[4][5][6] There are several technologies for the treatment of contaminated water with arsenic and lead ions such as coagulation-filtration, chemical precipitation, ion exchange and lime softening, among others. [7][8][9][10][11][12][13][14][15] In recent years, research has been conducted on low-cost and easily obtainable materials that may be useful for absorbing heavy metals. Among these materials are: activated charcoal, zeolites, chitosan, clays, biocarbon, and sand.…”