Evaluation of poly(ethylene diamine-trimesoyl chloride)-modified diatomite as efficient adsorbent for removal of rhodamine B from wastewater samples

Diatomite (D) as a low-cost and eco-friendly clay was modified by ethylene diamine (EDA)-trimesoyl chloride (TMC) polymer to achieve a novel adsorbent for efficient removal of rhodamine B dye (RB) from wastewater samples. The EDA-TMC polymer was grafted to the surface of diatomite by in situ interfacial polymerization. The prepared p(EDA-TMC)/D adsorbent was characterized by XRD, FTIR, and SEM/EDX techniques. The effective experimental parameters on the adsorption performance were optimized with factorial design analysis. The equilibrium data were better correlated by non-linear Langmuir model compared to non-linear Freundlich model. The Langmuir monolayer adsorption capacity of the p(EDA-TMC)/D adsorbent was determined as 371.8 mg g(-1). The key adsorption parameters were optimized by experimental design analysis. The kinetic findings showed the adsorption mechanism of RB onto p(EDA-TMC)/D adsorbent was well designated by the pseudo-second-order kinetic model. The thermodynamic results indicate that the RB adsorption had an exothermic character in thermal nature and was less favorable with increasing temperature from 20 to 60 degrees C. Furthermore, the adsorption/desorption yield of p(EDA-TMC)/D was still 80%/70% after 5(th) cycle and reduced to 60%/52% at the end of 8(th) cycle. Thus, the present study revealed that the developed p(EDA-TMC)/D composite had great adsorption potential for removal of RB from wastewater samples compared to that of different kinds of adsorbents reported in the literature.

Automated summary

A novel adsorbent based on diatomite modified by ethylene diamine and trimesoyl chloride polymer was developed for efficient removal of rhodamine B dye from wastewater. The adsorbent showed high adsorption capacity and good recyclability for rhodamine B.