In summary, the optimization of three parameters including malonic acid concentration, hydrogen peroxide (H2O2) concentration, and contact time using the Box-Behnken design for the leaching of copper (Cu) from laptop computer-sourced scrap printed circuit boards cut into the average dimension of 2 cm by 2 cm is reported. Although the use of PCB pieces instead of pulverized PCB reduces the metal recovery processes, great difficulty was encountered during the manual cutting of the large PCB boards to achieve the desired 2 cm by 2 cm sizes.