Improving the Environmental Friendliness of Graphite Oxidation Technology

It is noted that at obtaining 1 kg of oxidised graphite by dichromate technology, 180.21 thousand litres of waste water containing 1394.11 kg of sulphate ions and 224.11 kg of total chromium are generated. The technology of graphite oxidation is proposed, which consists in the fact that at the stage of oxidising mixture dilution waste water with pH = 0÷1 (very acidic) from the previous graphite oxidation process, containing the highest concentrations of sulphate ions and total chromium, was used. To produce 1 tonne of oxidised graphite using this technology, 176.7 thousand litres of waste water containing 1349.15 kg of sulphate ions and 223.06 kg of total chromium were discharged to the sludge fields. It was found that the composition of waste water (in terms of sulphate ions and total chromium) remains practically constant when its volume is reduced by 6.5 thousand litres. It is concluded that graphite oxidation using waste water reduces the ecological load on the environment.