Abatement of fluoride from water using manganese dioxide-coated activated alumina.

Batch adsorption of fluoride onto manganese dioxide-coated activated alumina (MCAA) has been studied. Adsorption experiments were carried out at various pH (3-9), time interval (0-6 h), adsorbent dose (1-16 g/l), initial fluoride concentration (1-25 mg/l) and in the presence of different anions. Adsorption isotherms have been modeled using Freundlich, Langmuir and Dubinin-Raduskevich isotherms and adsorption followed Langmuir isotherm model.

Chlorination byproducts, their toxicodynamics and removal from drinking water.

No doubt that chlorination has been successfully used for the control of water borne infections diseases for more than a century. However identification of chlorination byproducts (CBPs) and incidences of potential health hazards created a major issue on the balancing of the toxicodynamics of the chemical species and risk from pathogenic microbes in the supply of drinking water. There have been epidemiological evidences of close relationship between its exposure and adverse outcomes particularly the cancers of vital organs in human beings.

Adsorption of Co2+, Ni2+, Cu2+ and Zn2+ from 0.5 M NaCl and major ion sea water on a mixture of delta-MnO2 and amorphous FeOOH.

The pH(pzc) values of several mechanical mixtures of amorphous hydrous oxides of iron (amorphous FeOOH) and manganese (delta-MnO2) have been determined using the solid addition method. While the pH(pzc) of delta-MnO2 remains almost unchanged, the corresponding value for amorphous FeOOH tends to increase with increased proportion of delta-MnO2 in the mixtures. The adsorption behavior of Co2+, Ni2+, Cu2+, and Zn2+ with respect to pH on a mechanical mixture of 70% delta-MnO2 and 30% amorphous FeOOH from 0.

Adsorption of Co2+, Ni2+, Cu2+, and Zn2+ onto amorphous hydrous manganese dioxide from simple (1-1) electrolyte solutions.

The adsorption of Co2+, Ni2+, Cu2+, and Zn2+ onto amorphous hydrous manganese dioxide (delta-MnO2) has been studied using two methods, viz., isotherms at constant pH in the presence of buffer solution and pH variation in the absence of buffer solution from a fixed metal ion concentration. While the adsorption isotherm experiments were carried out in 0.

Adsorption of Co, Ni, Cu, and Zn on hydrous manganese dioxide from complex electrolyte solutions resembling sea water in major ion content.

Adsorption of Co, Ni, Cu, and Zn onto a poorly crystalline hydrous manganese dioxide (delta-MnO2) has been studied in complex electrolyte solutions such as (a) 0.5 M NaCl+0.054 M MgCl2, (b) 0.

The Electrical Double Layer at Hydrous Manganese Dioxide/Electrolyte Interface.

The interfacial properties of two hydrous oxides of manganese, namely an amorphous variety and a poorly crystalline synthetic birnessite, in different electrolyte media, have been studied by using a batch potentiometric titration procedure with a 72-h equilibration period. The data obtained by this procedure are more relevant to a natural water system than those obtained by the rapid titration method as reported earlier [J. Colloid Interface Sci.