A macrokinetic study of the WO3/Zn reaction diluted with NaCl

In this work, experiments with stoichiometric WO3 + 3Zn mixture, diluted with NaCl, were conducted for nanostructured tungsten synthesis. The reaction samples, preheated until 720 K, were self-ignited and reacted in the steady combustion regime. The temperature–time profiles in the combustion wave were collected over the NaCl interval from 1 to 6 mol, and the values of the combustion parameters (Tc, Uc) were evaluated. From these profiles the spatial distributions of heat generation rate ϕ(x) and degree of conversion η(x) in the combustion wave were received at different k values. The calculated activation energy for the combustion process was E = 55 ± 2 kJ mol−1. After the reduction experiments, pure tungsten nanopowder with particle size from 200 to 50 nm was obtained depending on NaCl concentration.