Use of natural sorbents in the processes of purification of absorbing potassium solutions of ammonia production

Today, the problem of purification of monoethanolamine (MEA) solutions and potassium-based, deethanolamine (DEA) activated solutions to purify gases from carbon dioxide is very acute at the enterprises of chemical industry for the production of ammonia in the synthesis scheme, at the stage of carbon monoxide conversion. Long-term use of such solutions (Carsol solution (25-28 % of КНСО3 and 1,.8 % of diethanolamine) and Benfield solution (29-30 % of КНСО3 and 2,9 % of diethanolamine)) leads to a decrease in their absorption capacity. At the stage of high-temperature regeneration, indirect processes of thermal diethanolamine decomposition occur in the volume of solutions, resulting in the formation of resinous substances and corrosion-active compounds, for removal of which additional stage for filtration of solutions on carbon filters is introduced into the flow chart. Experimental studies have been conducted at the Department of Chemical Technology and Water Purification to determine the adsorption capacity of activated bentonite clays for absorption of solutions of resinous substances and corrosion-active compounds. During the work, it has been established that bentonite clays activated by acid and alkaline activation have sufficient absorption capacity for resinous substances and corrosion-active compounds to replace the activated carbon used for these production purposes. It is revealed that the clay of acid activation is characterized by the lowest degree of absorption of the target components of the potassium solution. The clay of alkaline activation also absorbs K2CO3, KHCO3, diethanolamine and V2O5 in the process of adsorption but to a greater extent than the clay of acid activation. Activated carbon has the highest degree of absorption. Activated carbon has the highest degree of absorption. This disadvantage of activated carbon necessitates the constant replenishment of the absorbent solution with new portions of K2CO3, KHCO3, diethanolamine, which increases the production costs for purification of synthesis gas from carbon monoxide (IV)