Adsorção do corante azul de metileno utilizando um novo adsorvente obtido do coco de Jerivá (Syagrus romanzoffiana): caracterização, estudo cinético e termodinâmico

Abstract

A new adsorbent was developed from Jerivá coconut, a fruit found in the Atlantic Forest, and activated through high temperatures and with H3PO4. Carbon was characterized in terms of functional groups (FTIR), morphology (SEM and EDS) and porosity (BET and BJH). The efficiency of the charcoal developed from the Jerivá coconut was determined using the methylene blue model molecule as a contaminant. The main variables studied in this adsorption work were evaluated for statistical significance in the removal of methylene blue dye by means of activated carbon, showing that only the agitation of the system affects the process under the studied conditions. The adsorption kinetics were performed in three concentrations and adjusted to nonlinear models. The equilibrium occurred in 80 min and was sufficient to remove more than 99% of the initial concentration. The sorption isotherms were made at four temperatures and adjusted to five non-linear models. The data were better adjusted to Freundlich, suggesting the occurrence of multilayer adsorption. The process is spontaneous, favorable, endothermic and governed by physical adsorption. To obtain the parameters of the kinetic and isothermal models, six error functions were used. The results were promising, showing that the Jerivá coconut has potential for use as an adsorbent.