To achieve the carbon peak and neutrality targets

facilitate low-cost disposal of industrial solid wastes(namely semi-coke ash)

and develop new green and low-carbon composite materials

carrying out carbon capture using semi-coke ash is proposed

based on the existing semi-coke ash/sodium nitrate composite phase change heat storage materials. The performance of semi-coke ash and composite phase change heat storage materials before and after carbon sequestration is studied. The results indicate that

the optimal conditions for carbon sequestration in semi-coke ash are: gas composition of 20%CO_2/80%N_2

ventilation time of 40 minutes

and heating temperature of 650 ℃. Under the optimal experimental conditions

the carbon sequestration rate of semi-coke ash reaches 29.27%. The optimal mass ratio of the resulting composite phase change heat storage material

namely the carbon-sequestered semi-coke ash to NaNO3 is 5:5. It achieves a heat storage density of 288.65 J/g at 100～380 ℃

with better mechanical properties

thermal stability

and chemical compatibility. The use of carbon-sequestered semi-coke ash as a skeletal material to prepare composite phase change heat storage materials is highly feasible

providing a new approach for the resource utilization and carbon emission treatment of industrial solid wastes

namely semi-coke ash.