Adsorption of Ni(II) and Cd(II) from water by novel chelating sponge and the effect of alkali-earth metal ions on the adsorption

Manganese oxides are ubiquitous in soil, sediment and aquatic environment. Over the years, manganese oxides and their composites have proved to be effective as adsorbents for the removal of metal ions and contaminants from water/wastewater. Because of their unique chemical and physical properties, they have attracted widespread attention as excellent adsorbents. This review reports on recent research on the synthesis, characterization, and application of manganese oxides and their composites for wastewater treatment. The adsorption characteristics, including experimental conditions and mechanisms involved in the pollutant removal processes, are discussed. The review provides an overview of the research related to manganese oxides and their application, including future areas of research and limitations in the current body of research.

Manganese oxides and their application to metal ion and contaminant removal from wastewater

Mesoporous silica supported mono and bimetallic oxides are employed for the degradation of clofibric acid (CFA) in the heterogeneous electro-enhanced persulfate activation system. The oxidation system includes heterogeneous peroxydisulfate (PDS, S2O82−) activation coupled with electrochemical process, leading to the production of highly reactive radicals (SO4 − and OH). The influence of degradation reaction parameters, amongst the initial solution pH, current density, S2O82− concentration and catalyst loading, is investigated. Efficiency of catalyst to generate reactive radicals is confirmed using electron paramagnetic resonance (EPR) analysis and radical quenching experiments. The catalytic performance was evaluated in terms of CFA concentration abatement, while the stability of catalyst is followed by quantifying the metal leaching into the aqueous solution during reaction and the evolution of surface characteristics of the materials before and after reaction. The main degradation intermediates were identified in order to propose a possible degradation pathway of CFA.

Efficient degradation of clofibric acid by electro-enhanced peroxydisulfate activation with Fe-Cu/SBA-15 catalyst

Unraveling sorption of nickel from aqueous solution by KMnO4 and KOH-modified peanut shell biochar: Implicit mechanism.

Heavy metal is a serious problem nowadays. These heavy metals are discharged into water from various chemical industries. They are harmful for living organisms and it is necessary to eliminate these heavy metals to minimise risk of uptake by plants, animal and human. In the last few decades, several methods have been developed and extensively investigated for heavy metal removal. There are several methods for heavy metal removal: chemical precipitation, adsorption, ion exchange, membrane filtration, coagulation-flocculation and floatation. In this paper, an attempt is made to review various methodologies for heavy metal removal from wastewater with their advantages and disadvantages. It is evident from the literature survey that adsorption method is widely used over conventional methods, (i.e., chemical precipitation, ion exchange, membrane filtration, coagulation-flocculation and floatation) because of its low cost, availability and eco-friendly nature.

Chih Ping Lin

Papers

Application of Fered-Fenton and chemical precipitation process for the treatment of electroless nickel plating wastewater