Abstract: Process for upcycling a waste material to form alkylaromatic compounds is described herein. The process typically includes the steps of feeding a waste material containing hydrocarbon polymer(s) into a reactor containing a catalyst therein, and operating the reactor at a sufficient temperature for a sufficient period of time to convert the hydrocarbon polymer(s) to a liquid and/or wax product containing alkylaromatic compound(s). Each of the alkylaromatic compound(s) contains at least 10 carbon atoms. The catalyst contains a transition metal or a mixture of a transition metal and another metal. Optionally, the catalyst is dispersed on the surface of a support. The product may contain other unsaturated compounds, such as olefins. Typically, the reactor operates at a temperature in the range between 250° C. and 350° C. The total selectivity of the process to form the one or more alkylaromatic compounds is typically between 50 mol % and 95 mol %.