Synthesis of durian shell activated carbon by KOH activation using response surface methodology: characterization and optimization of process parameters

Abstract

The use of agricultural waste as a raw material for activated carbon production has the potential to offer a sustainable, low-cost, and environmentally friendly alternative to traditional methods. In this research, activated carbon was prepared from durian shell agricultural waste. Chemical activation with potassium hydroxide (KOH) via microwave heating was used in the process. The response surface methodology (RSM) technique was conducted to optimize the activation parameters, where the influences of various parameters, such as microwave power, carbon to potassium hydroxide (C/KOH) ratio, and activation times, on prepared durian shell char (PDSC) were investigated. The result from RSM model showed that the optimum values of each parameter were 691.3 W, 2.58, and 31.4 min for microwave power, C/KOH ratio, and activation times, respectively; these parameters corresponded to values of 239 mg/g and 965 mg/g for the methylene blue number (MBN) and iodine number (IDN), respectively. The properties of the obtained durian shell activated carbon (DSAC) were characterized using Brunauer–Emmett–Teller (BET), scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). The results revealed a pore volume of 0.3779 cm3/g with an amorphous structure, while BET surface area and mesopore surface area were identified to be 592.0 m2/g and 389.1 m2/g, respectively. The FTIR results showed the changes in functional groups after activation. Graphical abstract: (Figure presented.)