| 摘要 |
<p>PURPOSE:To recover a ketone organic solvent of high purity by bringing gas containing the ketone organic solvent into contact with a hydrophobic zeolite of alkali metal or alkaline-earth metal type having the mole ratio of SiO2/Al2O3 equal to or larger than a predetermined value, without causing ignition and lowering of adsorption performance. CONSTITUTION:Proton-type hydrophobic zeolite having the mole ratio of SiO2/ Al2O3 equal to 50 or more is converted to an alkali metal or alkaline-earth metal type one by neutralization method, ion exchange method, etc., and acidity of the zeolite is measured by pyridine temperature-programmed desorption method to make the quantity of solid acid of adsorbent 0.05mmol/g or less. When the gas containing a ketone organic solvent such as methyl ethyl ketone, cychlohexanone, etc., is brought into contact with the adsorbent thus produced, the ketone organic solvent can be adsorbed without causing decomposition or polymerization, while high adsorption performance is being maintained.</p> |
