Hence, the carbon-to-acetylene process based on barium carbide must be re-evaluated. In this study, a proof-of-concept of the negative carbon emission technology for the carbon-to-acetylene process and carbon dioxide utilization based on the barium cycle was first proposed (Fig. (a) Dependence of the BaC 2 yield and Ba mass balance on the reaction temperature and time; (b) BaC 2 reaction rate dependence on the reaction temperature and time. 6 SEM images of the reactant and products: (a and a 1 ) reactant and (b and b 1 ) heating products at 1150 °C, (c and c 1 ) at 1400 °C for 60 min, and (d and d 1 ) at 1550 °C for 30 min. In the barium carbide production unit, the powder mixture of barium carbonate and carbon-rich materials (biochar, coke, pyrolytic char, etc.)