In this study, the process of adsorption of modified rice straw was described using a mathematical description using kinetic and isothermal models. The models of pseudo-first order, pseudo-second order, Elovich and Lynuiver-Burke were used as kinetic models, and the Langmuir model and the Freundlich model are isothermal models.

Keywords: adsorption, adsorption kinetics, adsorption isotherms, Langmuir, Freindlich

The article suggests the use of agricultural wastes of the shell of the anacard nut, cultivated in the Republic of Cote d'Ivoire, as a sorption material. This carbon sorbent (0.5 g / l) was used to remove heavy metals, namely iron (Fe), C = 1.05 mg / l, aluminum (Al), C = 0.10 mg / l) from production waste water of the machine-building plant of LLC Rostselmash (Rostov-on-Don). According to the experimental data, the efficiency of metal removal depends on the sorption time and amounts to: for iron - from 28.6 to 97.1%, for aluminum - from 10 to 90% (Table 2). The concentration of metals in treated wastewater (iron C = 0.03 mg / l and aluminum C = 0.01 mg / l) corresponds to the norms of MPC (iron C = 0.1 mg / l, and aluminum C = 0.04 mg / l), which makes it possible to discharge them into the city water drainage system. From the experimental data, it was concluded that this material can be used as a sorbent.

Keywords: walnut shell anacard, Republic of Cote d'Ivoire, agricultural waste, carbon sorbent, wastewater treatment, heavy metals removal