Study on the key factors controlling the process in which sulfate green rusts remove bio-refractory organic pollutants

The removal of refractory and highly toxic organic pollutants in wastewater has become an important issue in the field of environmental governance. The mechanism and influencing factors of the process in which methyl orange and nitrobenzene were removed by sulfate green rust (GR-B) prepared by a semi-intermittent drip-adding method were investigated. The results showed that GR-B had an obvious removal effect on the two water-soluble organic pollutants that were arduous to degrade in nature. After 3 hours, around 89.6% of methyl orange and 96% of nitrobenzene were removed in the reduced system. The optimal reaction conditions were as follows: at 25 ℃ and pH 11, the optimal dosage was 33.6 g/L GR-B and 30 mg/L methyl orange or 100 mg/L nitrobenzene, respectively. By comparing and analyzing COD changes during the removal of methyl orange and nitrobenzene, it was preliminarily concluded that the reaction mechanism of the process in which GR-B was utilized to remove the two organic pollutants was adsorption and chemical reaction, respectively.