Open AccessRESEARCH INTO DYNAMICS OF ADSORPTION OF HEAVY METALS ON ACID-ACTIVATED BENTONITE
Author(s) -
D. Stetsenko,
Dmytro Yelatontsev
Publication year - 2021
Publication title -
zbìrnik naukovih pracʹ dnìprodzeržinsʹkogo deržavnogo tehnìčnogo unìversitetu. tehnìčnì nauki/zbìrnik naukovih pracʹ dnìprovsʹkogo deržavnogo tehnìčnogo unìversitetu. tehnìčnì nauki
Language(s) - English
Resource type - Journals
eISSN - 2617-8389
pISSN - 2519-2884
DOI - 10.31319/2519-2884.39.2021.13
Subject(s) - bentonite , sorption , adsorption , aluminosilicate , chemical engineering , chemistry , porosity , materials science , organic chemistry , catalysis , engineering
Acid activation of bentonite clay is a common way to obtain porous adsorbents of organic and inorganic substances. Acid activation with preservation of the layered structure is the initial stage of chemical modification. Acid treatment of natural aluminosilicates is aimed at increasing their adsorption capacity and specific surface area. In industrial practice, water treatment of heavy metals is in most cases carried out bypassing the liquid through a fixed layer of backfill. Therefore, in this study, we studied the dynamics of adsorption with the definition of the main characteristics of the process: the speed of the working zone, the coefficient of protective action, the length of the working layer, the loss of protective action time, the duration of the sorption column before leakage. In addition, the establishment of the basic laws of this process can be used to determine the optimal parameters of the sorption material at a given initial characteristic — the length of the layer of the sorption column, the filtration rate.
We have studied the possibilities of chemical modification of granular bentonite during acid-salt treatment. Through sorption columns with a height of 0.1; 0.2 and 0.3 m, filled with samples of modified bentonite, were passed model solutions of salts Fe2+, Mn2+, Cu2+ and Cd2+ with a concentration of cations of 0.01 g/dm3. The flow rate of the solution was 0.5; 1.0 and 1.5 m/h.
Experimental data show that the optimal sorption values are obtained for samples of modified bentonite: at the same height of the sorbent layer and flow rate, the duration of the layer before skipping in modified samples is 1.25—1.52 times higher than in unmodified ones. It is established that the sorption time before skipping mainly depends on the flow rate and the height of the sorbent layer. Thus, at a layer height of 0.3 m and the same rate of transmission of the solution, the sorption time is up to 3.5 times greater than at a layer height of 0.1 m for all investigated cations.