Carbonaceous material (SBC) was prepared from waste expanded polystyrene (EPS) and bentonite clay (BT) by pyrolysis in a tubular furnace under an inert atmosphere. The calculated average crystallite size of SBC was found to be 31.57nm from XRD analysis. FE-SEM studies showed that charring has changed the smooth-surfaced EPS and globular bentonite into uneven, porous flakes structure. The EDAX mapping results proved the co-existence of Al, Si, Fe, O, Na, Mg, Ca, Ti and C in SBC. BET analysis revealed the mesoporous nature of SBC and indicated its type IV isotherm behaviour. The minute loss rate value in water confirmed the water resistance, solidity and stability of the as-prepared carbonaceous material. Photo degradation in UV light for five different dyes showed immediate degradation at a catalyst dosage of 0.01g for 50ml/10ppm dye solution. The instantaneous discolouration of a mixture of organic dyes in the presence of UV light with micro quantities of SBC has become a cost-effective and simple method of up-cycling waste thermocol.