The utilization of chlorine-containing organic wastes remains an actual problem. In the present research, sponge-like porous Ni-Mo-W alloys were prepared and used as catalysts for the catalytic chemical vapor deposition of 1,2-dichloroethane. The synthesis of the alloys was performed via a facile approach of high-temperature reductive thermolysis of the preliminarily prepared multicomponent precursors. The formation of alloys of exact composition was proven by precise X-ray diffraction analysis. The catalytic activity of the alloys in the decomposition of 1,2-dichloroethane was studied in a flow-through reactor at 600 °C for 2 h. The simultaneous presence of Mo and W in the composition of the Ni-based alloys was shown to have a synergetic effect on the process efficiency. The diameter of these fibers was found to be comparable with the size of metal particles formed as a result of initial alloys self-disintegration under the action of the aggressive reaction medium.