Integration of in-situ chemical oxidation and permeable reactive barrier for the removal of chlorophenols by copper oxide activated peroxydisulfate.

In-situ chemical oxidation (ISCO) and permeable reactive barrier (PRB) have been used in field practices for contaminated groundwater remediation. In this lab-scale study, a novel system integrating ISCO and PRB using peroxydisulfate (PDS) as the oxidant and copper oxide (CuO) as the reactive barrier material was developed for the removal of 2,4-dichlorophenol (2,4-DCP), 2,4,6-trichlorophenol (2,4,6-TCP) and pentachlorophenol (PCP). The influences of chlorophenol concentration and flow rate on the system performance were first evaluated using synthetic solutions.

Recovery of phosphate and ammonia from wastewater via struvite precipitation using spent refractory brick gravel from steel industry.

Spent refractory brick (SRB) generated from the steel industry has a high magnesium content. In this study, a procedure was developed to utilize SRB gravels for efficient recovery of phosphate and ammonia from high strength wastewater via struvite (MgNHPO∙6HO(s)) precipitation. Mg and Ca were first leached from SRB gravels using nitric acid solution.

Activation of peroxydisulfate by carbon nanotube for the degradation of 2,4-dichlorophenol: Contributions of surface-bound radicals and direct electron transfer.

Carbon materials have been used to activate peroxydisulfate (PDS) for the degradation of organic pollutants. The mechanism involved, especially whether radicals are formed in these processes, is still under debate. In this research, multi-walled carbon nanotube (MWCNT) was employed to activate PDS for the removal of 2,4-dichlorophenol (2,4-DCP).

Degradation of 2,4-dichlorophenol by CuO-activated peroxydisulfate: Importance of surface-bound radicals and reaction kinetics.

Peroxydisulfate (PDS, SO) is a promising oxidant for water treatment and contaminated groundwater remediation. It requires activation to generate sulfate radical (SO) and hydroxyl radical (OH) for indirect oxidation of organic pollutants. Recently, efforts were devoted to developing PDS activation systems for direct oxidation of organic pollutants without producing radicals.