ASSESSMENT OF SORPTION PROPERTIES OF COKE FINES AND ITS RATIONAL USE FOR THE PURPOSE OF RESOURCE SAVING IN THE INDUSTRY

The influence of raw material factors (component composition of the charges, petrographic characteristics, indicators of technical, plastometric analyses, granulometric composition) and technological factors (coking period, process temperature) on the sorption properties of the carbonized product - coke was studied. For a coke fraction with a size of 2–5 mm, steam activation at a temperature of up to 850 °C with a process duration of 120 minutes is optimal. In this case, the average value of the specific surface area increases eight times compared to the raw material. Based on the research results, it is shown that such characteristics of coke as low humidity, low ash content, minimal yield of volatile substances, developed pore system and low cost make its use as a sorbent promising and economically justified. Thus, it was established that the obtained activated carbon has a porous structure consisting of meso- and macropores, and the value of the specific surface area is ~301 m2/g. The obtained sorbent is characterized by high sorption capacity for removing phenol (74,94 mg/g) and methylene blue (145 mg/g) from aqueous solutions, and when used for purification of tap water, the content of calcium, sulfates and hydrocarbonates decreases and the total mineralization decreases. The results of positive experience in using coke for adsorption of gold ions from cyanide solution are presented. The adsorbent was obtained by activating a coke fraction with a size of 2–5 mm with superheated steam at 850 °C for 30 min. The qualitative characteristics of the new coke adsorbent are as follows: ash content 4,5 %; adsorption activity for iodine 52 %; specific surface area, 600 m2/g, developed porous structure, with mainly round or oval pores with a cross-sectional size of up to 20 μm, and the total pore volume is 0.4 cm3/g. The obtained dependences for predicting the sorption capacity for alkali and acid and the adsorption activity for iodine, taking into account the vitrinite content and the yield of volatile substances of the charge, are characterized by high correlation coefficients r (0,912, 0,927 and 0,937, respectively), therefore they can be recommended for predicting the indicated indicators.