An environment-friendly technique for direct air capture of carbon dioxide via a designed cellulose and calcium system

As a carbon negative emission technique for the ever-increasing demand of sustainable development and climate control, the direct air capture (DAC) has attracted tremendous research attention in recent years. By means of DAC, herein a facile method has been developed to capture CO2 with a designed system of biomass cellulose-added Ca2+ solution. The resultant calcite CaCO3 is found to be uniformly attached to the cellulose fibrils. Compared to a non-cellulose system, cellulose raises the CO2 capture efficiency by 32%. The CO2 capture capacity reaches as high as 7.3 mmol g−1. In the composite [email protected]3 (CelCa), the chemical interfacial coupling has been revealed by both experimental findings and density functional theory calculations. Two routes have been suggested for the release of CO2. Firstly, CelCa is shaped into a practical filter, which accomplishes an ion exchange with Pb2+ that comes from the discharge effluents of factories. The [email protected]3 (CelPb) has been accessible, which would significantly lower the calcination temperature for CO2 release and consume much less energy than CaCO3. Secondly, CelPb is treated with acid to release CO2, while cellulose and calcium ion are re-cycled. In short, the whole processing design is cost effective and environment friendly, which suggests its good prospective application in the field of CO2 emission control.