COMPARISON OF THE ION-EXCHANGE PROPERTIES OF CARBON ION-EXCHANGERS SYNTHESIZED ON THE BASIS OF APRICOT AND PEACH STONE SHELLS

Abstract

The aim of the work is the synthesis of carbon ion-exchangers from the apricot and peach stone shells, the study of their ion exchange properties, including in the process of purification wastewaters from radioactive isotopes, and comparison of ion exchange properties obtained on the basis of shells of apricot and peach stones of carbon ion- exchangers. The process of carbonization of the apricot stone shells in the temperature interval of 400-450⁰C and of the peach stone shells in the temperature interval of 450- 500⁰C with the process duration of 1-2 hours in the nitrogen medium have been studied. Activation was carried out in the heated water vapor medium at temperatures of 750- 1000⁰C and with the process duration of 1-5 hours. To improve the ion-exchanging and selective properties of the obtained stone’s carbons, the oxidation process of carbonized and activated carbon was studied. The study of the ion-exchanging properties of carbon ion- exchangers (exchange capacity, the number of strong-acid carboxyl, weak-acid carboxyl and phenol groups, activity by adsorption Sr²⁺ and Cs+) were carried out. The obtained samples have been tested and investigated in detail at the Armenian Nuclear Power Plant. The investigations of the effectiveness of the filtering capability of the apricot and peach stone shells carbon ion-exchangers have been held in laboratory conditions NPP. The experiments have shown that the synthesized carbon ion-exchangers are capable of reducing the content of radioactive isotopes, in particular ¹³⁴Cs and ¹³⁷Cs isotopes, in the wastewater of the Armenian NPP by about 1000 times.