A lanthania modified MgO catalyst, La-MgO, has been developed and characterized by adsorption methods, X-ray diffraction method (XRD), scanning electron microscopy (SEM), temperature-programmed desorption of ammonia (NH3-TPD) and CO2 (CO2-TPD). The La-MgO has been proved to be a highly efficient and stable dehydrochlorination chemsorbent; moreover, it shows prominent catalytic degradation ability for a typical PVC-containing polyolefins (polypropylene/polyvinyl chloride), i.e., higher degradation rate and superior liquid quality, which will be very useful in the recycling of chlorine-containing waste plastics. (C) 2007 Elsevier B.V. All rights reserved.