Present industrial decarbonization technologies require an active CO_(2)-concentration system,often based on lime reaction or amine binding reactions,which is energy intensive and carries a high CO_(2)-footprint.Here ...Present industrial decarbonization technologies require an active CO_(2)-concentration system,often based on lime reaction or amine binding reactions,which is energy intensive and carries a high CO_(2)-footprint.Here instead,an effective process without active CO_(2)concentration is demonstrated in a new process-termed IC2CNT(Insulationdiffusion facilitated CO_(2) to Carbon Nanomaterial Technology)decarbonization process.Molten carbonates such as Li_(2)CO_(3)(mp 723℃)are highly insoluble to industrial feed gas principal components(N2,O_(2),and H2O).However,CO_(2) can readily dissolve and react in molten carbonates.We have recently characterized high CO_(2) diffusion rates through porous aluminosilicate and calcium-magnesium silicate thermal insulations.Here,the CO_(2) in ambient feed gas passes through these membranes into molten Li_(2)CO_(3).The membrane also concurrently insulates the feed gas from the hot molten carbonate chamber,obviating the need to heat the(non-CO_(2))majority of the feed gas to high temperature.In this insulation facilitated decarbonization process CO_(2)is split by electrolysis in the molten carbonate producing sequestered,high-purity carbon nanomaterials(such as CNTs)and O_(2).展开更多
It is hypothesized and demonstrated that thermal insulation membranes can provide an effective barrier to heat flow and simultaneously facilitate effective CO_(2)diffusion.Decarbonization technology often requires a C...It is hypothesized and demonstrated that thermal insulation membranes can provide an effective barrier to heat flow and simultaneously facilitate effective CO_(2)diffusion.Decarbonization technology often requires a CO_(2)concentration system,often based on amine binding or lime reaction,which is energy intensive and carries a high carbon footprint.Alternatively,C2CNT electrolytic molten carbonate decarbonization does not require CO_(2)pre-concentration and also provides a useful product(graphene nanocarbons)from the captured CO_(2).Here,a method of effective CO_(2)diffusion is demonstrated that simultaneously thermally insulates the decarbonization source gas from the high-temperature C2CNT system.Open pore,low-density,thermal insulations are implemented as membranes that facilitate effective CO_(2)diffusion for high-temperature decarbonization.Selected,high-temperature,strongly thermal insulating,silica composites are measured with porosities,,exceeding 0.9(>90%porosity),and which display,as measured by SEM,large open channels facilitating CO_(2)diffusion.A derived and experimentally verified estimate for the CO_(2)diffusion constant through these membranes is DM-porous=ε^(3/2)DCO_(2),where DCO_(2)is the diffusion constant in air.DM-porous is applicable to a wide-range of CO_(2)concentrations both in the air and N2.The CO_(2)diffusion constant is translated to the equivalent decarbonization system mole influx of CO_(2)and shown capable of sustaining high rates of CO_(2)removal.Combined with the strong electrolyte affinity for CO_(2)compared to N_(2),O_(2),or H_(2)O,the system comprises a framework for decarbonization without pre-concentration of CO_(2).展开更多
文摘Present industrial decarbonization technologies require an active CO_(2)-concentration system,often based on lime reaction or amine binding reactions,which is energy intensive and carries a high CO_(2)-footprint.Here instead,an effective process without active CO_(2)concentration is demonstrated in a new process-termed IC2CNT(Insulationdiffusion facilitated CO_(2) to Carbon Nanomaterial Technology)decarbonization process.Molten carbonates such as Li_(2)CO_(3)(mp 723℃)are highly insoluble to industrial feed gas principal components(N2,O_(2),and H2O).However,CO_(2) can readily dissolve and react in molten carbonates.We have recently characterized high CO_(2) diffusion rates through porous aluminosilicate and calcium-magnesium silicate thermal insulations.Here,the CO_(2) in ambient feed gas passes through these membranes into molten Li_(2)CO_(3).The membrane also concurrently insulates the feed gas from the hot molten carbonate chamber,obviating the need to heat the(non-CO_(2))majority of the feed gas to high temperature.In this insulation facilitated decarbonization process CO_(2)is split by electrolysis in the molten carbonate producing sequestered,high-purity carbon nanomaterials(such as CNTs)and O_(2).
文摘It is hypothesized and demonstrated that thermal insulation membranes can provide an effective barrier to heat flow and simultaneously facilitate effective CO_(2)diffusion.Decarbonization technology often requires a CO_(2)concentration system,often based on amine binding or lime reaction,which is energy intensive and carries a high carbon footprint.Alternatively,C2CNT electrolytic molten carbonate decarbonization does not require CO_(2)pre-concentration and also provides a useful product(graphene nanocarbons)from the captured CO_(2).Here,a method of effective CO_(2)diffusion is demonstrated that simultaneously thermally insulates the decarbonization source gas from the high-temperature C2CNT system.Open pore,low-density,thermal insulations are implemented as membranes that facilitate effective CO_(2)diffusion for high-temperature decarbonization.Selected,high-temperature,strongly thermal insulating,silica composites are measured with porosities,,exceeding 0.9(>90%porosity),and which display,as measured by SEM,large open channels facilitating CO_(2)diffusion.A derived and experimentally verified estimate for the CO_(2)diffusion constant through these membranes is DM-porous=ε^(3/2)DCO_(2),where DCO_(2)is the diffusion constant in air.DM-porous is applicable to a wide-range of CO_(2)concentrations both in the air and N2.The CO_(2)diffusion constant is translated to the equivalent decarbonization system mole influx of CO_(2)and shown capable of sustaining high rates of CO_(2)removal.Combined with the strong electrolyte affinity for CO_(2)compared to N_(2),O_(2),or H_(2)O,the system comprises a framework for decarbonization without pre-concentration of CO_(2).
