Improving efficiency and feasibility of subcritical water debromination of printed circuit boards E-waste via potassium carbonate adding

Waste printed circuit boards (WCBs) were debrominated under hydrothermal treatment, using potassium carbonate as an alkaline additive to improve debromination efficiency (DE). Two different high-pressure reactors used: a 1-L stirred reactor, where the evolution of DE was followed over time at low CO32?/Br? ratio (1:25), and elementary 0.1-L non-stirred used find optimal parameters simplify (HTD) process. Considering both reactors, experiments conducted changing temperature (200 °C, 225 250 275 °C), also anionic (1:50, 1:25, 1:10, 1:5, 1:2.5, 1:1, 2:1, 4:1) solid/liquid (1:10, 1:2) in case reactor. No metallic catalyst required. A maximum about 98.9 wt % reached agitated vessel °C after 4 h, with additive/bromine 1:25. Similar (99.6 %) achieved reactor only 2 4:1 1:2. Concerning solid phase behaviour during debromination, 5 net calorific value (NCV) lost complete HTD treatment WCB.