The dehalogenation measurements could be carried out with the decomposition of plastic wastes
simultaneously or successively. This paper reviewed the progresses in dehalogenation followed by thermochemical
conversion of plastic-containing wastes for clean energy production. The pre-treatment
method of MCT or HTT can eliminate the halogen in plastic wastes. The additives such as alkali-based
metal oxides (e.g., CaO, NaOH), iron powders and minerals (e.g., quartz) can work as reaction mediums
and accelerators with the objective of enhancing the mechanochemical reaction. The dehalogenation of
waste plastics could be achieved by co-grinding with sustainable additives such as bio-wastes (e.g., rice
husk), recyclable minerals (e.g., red mud) via MCT for solid fuels production. Interestingly, the solid fuel
properties (e.g., particle size) could be significantly improved by HTT in addition with lignocellulosic biomass.
Furthermore, the halogenated compounds in downstream thermal process could be eliminated by
using catalysts and adsorbents. Most dehalogenation of plastic wastes primarily focuses on the transformation
of organic halogen into inorganic halogen in terms of halogen hydrides or salts. The integrated
process of MCT or HTT with the catalytic thermal decomposition is a promising way for clean energy
production. The low-cost additives (e.g., red mud) used in the pre-treatment by MCT or HTT lead to a
considerable synergistic effects including catalytic effect contributing to the follow-up thermal
decomposition.