As(iii) removal through catalytic oxidation and Fe(iii) precipitation

Area of Science:

• Environmental Chemistry
• Catalysis
• Water Treatment

Background:

• Arsenite (As(iii)) poses a significant threat to water quality and human health.
• Effective removal of arsenic species from wastewater is crucial for environmental protection.

Purpose of the Study:

• To investigate the catalytic oxidation of arsenite (As(iii)) to arsenate (As(v)) and subsequent precipitation of As(v) using iron ions (Fe(iii)).
• To evaluate the efficacy of a Pt/SiO2 catalyst in enhancing arsenic removal from wastewater.

Main Methods:

• Utilized a Pt/SiO2 catalyst to facilitate the oxidation of As(iii) to As(v) in the presence of atmospheric oxygen.
• Investigated the combined effect of the Pt/SiO2 catalyst and Fe(iii) precipitant for arsenic removal.

Main Results:

• The Pt/SiO2 catalyst served as a reaction site for the oxidation of As(iii) with oxygen.
• The combination of Pt/SiO2 catalyst and Fe(iii) significantly improved the removal of As(iii) via precipitation.
• Pt/SiO2 acted as both an oxidation site for As(iii) and a co-precipitation site with Fe(iii).

Conclusions:

• The developed catalytic oxidation and precipitation method using Pt/SiO2 and Fe(iii) is highly effective for removing arsenite from wastewater.
• The Pt/SiO2 catalyst plays a dual role in enhancing arsenic removal efficiency through oxidation and facilitating precipitation.