Activated carbons from peach stones and waste polyolefin wax were prepared and tested as a host matrix of nanodispersed zinc ferrite. Nitrogen physisorption, Boehm method, XRD, TPR with hydrogen, FTIR, UV–Vis and Moessbauer spectroscopy were applied to investigate the activated carbon characteristics and the state of loaded on it metal oxide particles. The higher microporosity and lower surface functionality, typical of activated carbon from waste biomass, facilitated the formation of more finely dispersed, located into the micropores iron and zinc oxide nanoparticles. This promoted formation of Zn rich ferrite phase which ensures high catalytic activity in methanol decomposition.