Selective adsorption of carbon di:oxide gas - by the use of deca-dodecasil e$, a clathrasil-type cpd

摘要

The use of deca-dodecasil 3R (DD3) for the adsorption and extraction of CO2 contd. in a gaseous mixt. An appts. for the adsorption and desorption of CO2 using DD3 and the use of DD3 for measurement and/or detection of CO2 is also claimed. USE/ADVANTAGE - DD3 is partic. useful in the elimination of CO2 from confined spaces such as submarines and space vessels. The powering of CO2 content in air is also important in the conservation of vegetables and fruits. The nature of DD3 is such that the ratio of Si:Al is infinite, thus giving a `total silica' phase. There are no ionic sites, such as SiO- or SiOH and no cations are present in the porous vol. Thus the prod. presents a surface with hydrophobic properties. The cpd., before thermal treatment, is a clathrate prod. of formula 120 SiO2.6M10.9M12.6M19, with M12 = N2 and M19 = C10NH17 (1-amino-adamantane). After thermal treatment at 500 deg.C, a `clathrasil' is obtd. with a cell structure comprising 3 types of inter-connected cavities, which has zeolite-like properties. DD3 shows a high selectivity to adsorption of CO2 and also a high resistance to water adsorption (due to its hydrophobic properties). Performance is thus unaffected by variation in humidity of a gas mixt. Adsorption can be carried out at ambient temp. and pressure, i.e. 10-30 deg.C and atmos. pressure or above a wider range of temp. if desired DD3 can easily be re-generated.