The effect of co-impregnated acids on the performance of Zn-based broad spectrum respirator carbons

► Respirator carbons prepared from Zn(NO3)2 and different acids. ► Multi-gas adsorption capacity determined after impregnation and thermal treatments. ► Powder X-ray diffraction used to determine impregnant phase after heating. ► Impregnant phase present after heating was important for gas adsorption capacity. ► IACs prepared from Zn(NO3)2 and HNO3, C2H4O2 or HCl had multi-gas capacity.