Application of Chlorine Dioxide for Restoring the Adsorption Capacity of Activated Carbon Wasted under Industrial Conditions

Abstract

The effect produced by the treatment of wasted activated carbons with chlorine dioxide on the restoration of the adsorption capacity of sorbents resided for a long time in the adsorbers incorporated into the tap water post-treatment system of a beverage production plant was investigated. The studies were performed by treating the carbon samples with chlorine dioxide solutions of different concentration, steaming at a temperature of 150°C, and combining the treatment with oxidant solutions and steaming on the laboratory bench. The structural and sorption characteristics of carbons were calculated according to the Langmuir and Freundlich models, and the iodine number of the studied samples was also determined. It has been shown that the combination of oxidative treatment with chlorine dioxide and the steaming of activated carbon provides not only the sanitation of the sorbent in an industrial adsorber, but also the restoration of the structural and sorption properties of carbon. The series of performed experiments can restore the adsorption capacity of activated carbon to ~75–85% of the initial level. The degree of restoring the adsorption capacity of sorbents depends on the time of load operation in the adsorption filters. Depending on the time of carbon operation in an adsorber, the microporous space of the sorbent can be completely or partially purified. This fact plays an important part in the removal of organochlorine compounds formed during the final disinfection of water.