Co-processing of petroleum vacuum residue (BVR) with plastics (polypropylene, bakelite), coal (Samla coal), and biomass (bagasse, Calotropis procera) was carried out in a thermogravimetric analyzer (TGA) reaction system in nitrogen atmosphere with a view to comparing the process of the mixture with those of the individual components. Experiments were conducted at heating rate of 40 8C/min, in the temperature range of 30-900 8C. Based on the results obtained, three temperature regimes were selected for studying the non-isothermal kinetics of TGA of individual BVR, plastics, coal, biomass as well as of the co-processing of these with BVR, i.e., below 400 8C, between 400 and 500 8C and above 500 8C. The kinetic studies were performed using Coats and Redfern kinetic-modeling equations. The overall activation energies were 60.83 kJ/mole for petroleum residue, 99.41 kJ/mole for polypropylene, 21.08 kJ/mole for coal, 22.68 kJ/mole for C. procera and 31.9 kJ/mole for the mixture of these four materials. Thus, it has been found that there exists an overall synergy, when four materials were co-processed together. The overall orders and activation energies change during co-processing of two, three or four different macromolecules including petroleum residue as observed presently. The results obtained are being reported.