Study On Efficient Adsorbents Of Power Plant CO₂Capture Technology

With the greenhouse effect becoming increasingly prominent, the capturation andseparation of carbon dioxide, which is one of the main gases conducing to greenhouseeffect, has attracted the attention of the world. The flue gas produced by power plant isthe main CO₂exhaust source in industrial production. The separation of the carbondioxide captured from flue gas and the application of it into the soda ash industry will notonly mitigate the influence of greenhouse effect, but also save a lot of carbon dioxideresources, so it is a win-win mechanism.A series of novel CO₂adsorbents for CO₂removal were prepared by introducingN-（3-aminopropyl）-3-ethyoxylsilane（APTES） as the modifying agent into organizedmesoporous alumina and SBA-15as the mesoporous material, and the novel adsorbentwas prepared by introducing MgO as the modifying agent on CaO carrier. The propertiesof the adsorption materials before and after surface modification were characterized byX-ray diffraction（XRD）, Nitrogen adsorption-desorption instrument, transmissionelectron microscopy（TEM）, scanning electronic microscope（SEM）. The content of thetest is listed as follow:In this paper, inorganic aluminate was applied as the aluminum source, nonionicsurfactant as the template agent, and salvolatile as the precipitant. The organizedmesoporous alumina prepared was of high specific surface area, narrow pore sizedistribution, and presented regularly worm-like pore structure. The effect of the gas flowrate, adsorption temperature, bed height, loading capacity to the adsorption capabilitywere investigated. The result shows that organized mesoporous alumina with themodification of amino has better adsorption properties of CO₂with the steady adsorptionquantity of44.33mg/g, compared with organized mesoporous alumina. Organizedmesoporous alumina with the modification of amino has better regenerate capability withthe adsorption quantity of29.65mg·g-1after recycling of adsorbing material for6times.In this paper, the mesoporous silica zeolite（SBA-15） with regular hexagon porestructure was synthesized by appling P123as the single template TEOS as silica source.The effect of the gas flow rate, adsorption temperature, bed height, loading capacity tothe adsorption capability are investigated. The result shows that SBA-15with themodification of amino has better adsorption properties of CO₂with the steady adsorptionquantity of121.85mg/g, compared with SBA-15. SBA-15with the modification of amino has better regenerate capability with the adsorption quantity of110mg/g afterrecycling of adsorbing material for7times.The attenuation of the calcium-based sorbents with special teeatment was studied.Magnesium oxide was applied as additive to alleviate the attenuation of the absorptioncapability of calcium oxide in order to get more active absorption agent applied tocircular reaction. Meanwhile, the effect of the adsorption temperature, gas flow rate onthe adsorption capacity were investigated. The result shows that CaO with themodification of MgO has better adsorption properties of CO₂with the steady adsorptionquantity of320mg/g, compared with CaO. CaO with the modification of MgO has betterregenerate capability with the adsorption quantity of295mg/g after recycling ofadsorbing material for10times.In this paper, solid absorbent’s adsorption properties of CO₂was studied, andadsorption properties of three kinds of absorbents were compared. Organizedmesoporous alumina initially applied was of good effect and compared with commonalumina,it possessed larger specific surface area; SBA-15possessed larger specificsurface area and regular hexagon pore structure; CaO possessed better prospects fordevelopment with merits of cheapness, availability and large adsorption quantity.