Metallic iron (Fe)-based materials for aqueous phosphate removal: A critical review.

The discharge of excessive phosphate from wastewater sources into the aquatic environment has been identified as a major environmental threat responsible for eutrophication. It has become essential to develop efficient but affordable techniques to remove excess phosphate from wastewater before discharging into freshwater bodies. The use of metallic iron (Fe) as a reactive agent for aqueous phosphate removal has received a wide attention.

Investigating the Fe/HO systems using the methylene blue method: Validity, applications, and future directions.

An innovative approach to characterize the reactivity of metallic iron (Fe) for aqueous contaminant removal has been in use for a decade: The methylene blue method (MB method). The approach considers the differential adsorptive affinity of methylene blue (MB) for sand and iron oxides. The MB method characterizes MB discoloration by sand as it is progressively coated by in-situ generated iron corrosion products (FeCPs) to deduce the extent of iron corrosion.

The mechanism of contaminant removal in Fe(0)/HO systems: The burden of a poor literature review.

The global effort to mitigate the impact of environmental pollution has led to the use of various types of metallic iron (Fe(0)) in the remediation of soil and groundwater as well as in the treatment of industrial and municipal effluents. During the past three decades, hundreds of scientific publications have controversially discussed the mechanism of contaminant removal in Fe(0)/HO systems, with the large majority considering Fe(0) to be oxidized by contaminants of concern. This view assumes that contaminant reduction is the cathodic reaction occurring simultaneously with Fe oxidative dissolution (anodic reaction).

Characterizing the reactivity of metallic iron for water defluoridation in batch studies.

The suitability of metallic iron (Fe(0)) for water defluoridation is yet to be understood. Fluoride removal ([F] = 20.0 mg L) and Orange II discoloration ([Orange II] = 10.

Investigating the suitability of Fe packed-beds for water defluoridation.

A commercial granular metallic iron (Fe) specimen was used to evaluate the suitability of Fe materials for removing aqueous fluoride (F) (water defluoridation). Experiments were performed to characterize the defluoridation potential of the tested Fe as influenced by the presence of chloride (Cl) and bicarbonate (HCO) ions using tap water (HO) as operational reference system. Duplicate column studies were conducted for 120 days (4 months) using an initial F concentration of 22.

Metallic iron for safe drinking water provision: Considering a lost knowledge.

Around year 1890, the technology of using metallic iron (Fe) for safe drinking water provision was already established in Europe. The science and technology to manufacture suitable Fe materials were known and further developed in this period. Scientists had then developed skills to (i) explore the suitability of individual Fe materials (e.