potential use of foundry sand as heterogeneous catalyst in solar photo- fenton degradation ofherbicide isoproturon

this study deals with employing foundry sand (fs) as new low cost iron source in heterogeneousphoto-fenton process for the degradation of herbicide isoproturon (ipu) in aqueous solution. thecharacterization of the fs by eds confirmed presence of iron (23%) required for photo-fenton andsimultaneously confirmed absence of any heavy metals which may be susceptible to leaching. the photo-fenton effects of different reaction parameters like h2o2 concentration [h2o2]0, operating ph, initialconcentration of ipu [c0], fs dose, recycling of fs, effect of area/volume ratio were investigated. resultsshowed that the maximal removal efficiency were achieved when reaction parameters were [h2o2]0= 2.2 mm,ph 3, fs dose=0.5 g/l, [c0] =25 mg/l. under optimum condition, 97% degradation efficiency of ipu wasachieved within 150 min of reaction. the catalyst recycling test was performed and fs was effectivelyrecycled for 4 times with 20% reduction in degradation efficiency. sem-eds analysis of recycled fs confirmedmorphology of fs unchanged. solar baffled batch reactor (sbbr) with recirculation confirmed 70% degradationof ipu after 6 h. ipu mineralization was confirmed with toc reduction, nh4+ generation along with formationof intermediates as confirmed through lc-ms.