Impacts of environmental levels of hydrogen peroxide and oxyanions on the redox activity of MnO₂ particles

Abstract

Despite the widespread presence of hydrogen peroxide in surface water and groundwater systems, little is known about the impact of environmental levels of H2O2 on the redox activity of minerals....

Impact of Mn2+ in bisphenol A degradation by chelating agents-assisted manganese dioxide: Mechanism understanding and efficiency evaluation

“…The adsoprtion of BPA on MnO 2 was verified and as mentioned in a previous article it remains negligible [28]. The degradation of BPA by PP complexed manganese dioxide (MnO 2 ) in the presence of Mn 2+ was investigated.…”

“…The effects of solution pH and inorganic ions were investigated to evaluate the adaptability of the MnO 2 /PP/Mn 2+ system in a natural aquatic environment. Moreover, based on the previous report, increasing solution pH from 4.0 to 8.0 leads to the reductive potential of MnO 2 decreasing from 0.99 to 0.76 V [28]. Therefore, both the direct oxidation of BPA by MnO 2 and the amounts of Mn(III) species generated in the reaction will be reduced at higher solution pH.…”

Synchronous Moderate Oxidation and Adsorption on the Surface of γ-MnO2 for Efficient Iodide Removal from Water

“…Moreover, the I – reductive dissolution effects toward MnO 2 contributed to the formation of Mn­(II), and positive Mn 2+ greatly favored the adsorption of anions such as phosphate and silicate, which reduced the adsorption of I – accordingly. The formed Mn­(II) may readsorb onto active sites on the MnO 2 surface and inhibit its oxidation ability; the inhibition effect is more significant in the presence of phosphate and silicate . Dissolved silicate tends to adsorb onto colloidal MnO 2 by hydrogen bonds and cover the MnO 2 surface; further particle aggregation and growth are inhibited accordingly .…”

“…The formed Mn(II) may readsorb onto active sites on the MnO 2 surface and inhibit its oxidation ability; the inhibition effect is more significant in the presence of phosphate and silicate. 42 Dissolved silicate tends to adsorb onto colloidal MnO 2 by hydrogen bonds and cover the MnO 2 surface; further particle aggregation and growth are inhibited accordingly. 43 Additionally, phosphate and silicate form oxygen anion ternary complex with Mn(II,III) at the vacancy of MnO 2 and interfere with the electron transfer and structure arrangement.…”

Cytosol Peroxiredoxin and Cell Surface Catalase Differentially Respond to H2O2 Stress in Aspergillus nidulans

“…Conidia from WT and PrxA gene disruption strain (∆prxA) were treated with a series of H 2 O 2 concentrations from 0 to 300 mM to investigate the performance of conidial PrxA. Very high concentrations of H 2 O 2 were used here because dormant conidia are extremely resistant to H 2 O 2 as described previously, but in fact the environmental H 2 O 2 generally does not exceed a few millimolar [22][23][24]. After a 20-min exposure, the dormant conidia were plated on MM plates and the colony numbers were used to determine the fungal H 2 O 2 tolerance.…”