Multifunctional activated carbon with antimicrobial property derived from Delonix regia biomaterial for treatment of wastewater

In this work, we report the development of a multifunctional high surface area activated carbon (DRP), from a biomaterial, Delonix regia, with antimicrobial potential and demonstrated its applicability towards removal of two reactive dyes, Reactive Red (RR-120) and Reactive Blue (RB-4) with an adsorption capacity of similar to 6.36 and 24 mg.g(-1) respectively. The newer multifunctional activated carbon was prepared from the deseeded pods of Delonix regia through thermo-chemical surface modification and characterized for surface and morphological characteristics, chemical composition, and thermal stability. DRP exhibited a high surface area of 1577 m(2).g(-1) with various active functional groups. The decolourisation efficiency achieved was very high, similar to 98% for both the dyes. The effects of various operating parameters like pH, initial dye concentration, adsorbent dosage, surfactant, salt etc. were investigated and the batch adsorption equilibrium data in each dye system was analyzed with various isotherms-Langmuir, Freundlich, and Tempkin. The kinetics of the adsorption process was best represented by pseudo-second order kinetic model and the adsorption efficiency was also illustrated in the binary system of varying dye compositions. DRP could successfully reduce the microbial growth of Gram positive B. subtilis with a higher zone of inhibition.