A resource-utilization way of the waste printed circuit boards to prepare silicon carbide nanoparticles and their photocatalytic application.

A resource-utilization strategy of the waste PCBs was developed: preparation of high value-added silicon carbide (SiC) nanoparticles using the waste PCBs as both silica and carbon precursors. The preparation process contained three optimized steps: acid wash pretreatment with 3 mol L-1 nitric acid at 60 °C for 96 h, low-temperature pyrolysis at 500 °C to allow the epoxy resin to decompose into carbon, and high-temperature pyrolysis at 1600 °C (in situ carbothermal reduction) to gain pure SiC nanoparticles. The pseudo first-order reaction rate constant (k) of the p-n heterojunction of SiC/TiO2 towards the photocatalytic degradation of methylene blue was 0.0219 min-1, 3.42 and 3.98 times that of TiO2 and no acid washed-SiC/TiO2, respectively.