CO2 capture and preparation of spindle-like CaCO3 crystals for papermaking using calcium carbide residue waste via an atomizing approach.

Spindle-like CaCO₃ crystals with controllable sizes for papermaking were successfully prepared using CO₂ (8% CO₂/N₂ mixture gas) and calcium carbide residue (CCR) waste, a by-product of acetylene gas and polyvinyl chloride production, as the raw materials by an atomization method at room temperature. The influences of solution concentration, reaction temperature, and gas/liquid flow rate ratios on the properties of the CaCO₃ crystal were systematically investigated, and a possible atomization mechanism was proposed. The size of the as-prepared CaCO₃ crystal with pure calcite phase was turned from 4.71×4.02 µm to 1.82×1.12 µm by adjusting the reaction conditions. The application of the as-prepared CaCO₃ crystals from CCR waste as a filler for papermaking was explored. The R475 blue light whiteness of paper was increased from 77.3 to 80.6 with 11.4% CaCO₃ crystals. [ABSTRACT FROM AUTHOR]