Activated carbons from golden shower upon different chemical activation methods: Synthesis and characterizations

Activated carbons (ACs) were synthesized from golden shower (GS) through chemical activation. Two synthesis processes were used: one-stage and two-stage processes. In the one-stage process, GS that was impregnated with K2CO3 was directly pyrolyzed (GSAC), and the two-stage process consisted of (1) pyrolytic or hydrolytic carbonization to produce biochar or hydrochar and (2) subsequent chemical activation was defined as GSBAC and GSHAC, respectively. The activated carbon's characteristicsthermal stability and textural, physicochemical, structural, and crystal propertieswere thoroughly investigated. Results demonstrated that the characteristics of activated carbons strongly depend on the method used for their synthesis. The Brunauer-Emmett-Teller surface area followed the order GSAC (1413m(2)/g) > GSHAC (1238m(2)/g) > GSBAC (812m(2)/g). The existence of acidic groups was determined through Fourier transform infrared spectroscopy and Boehm titration. The excellent adsorptive capacities of the activated carbons were confirmed from the iodine number (1568-2695mg/g) and methylene number (143-233mg/g).