| 摘要 |
The invention provides partially pyrolyzed particles of a macroporous synthetic polymer having properties suitable for use in adsorption, molecular screening and/or catalysis and a resistance to crushing and particle sloughage greater than that of known spherical adsorbent particles or that of granular activated carbon, comprising the product of controlled thermal degradation of a macroporous synthetic polymer containing a carbon-fixing moiety and derived from one or more ethylenically unsaturated monomers, or from monomers which may be condensed to yield macroporous polymers, or mixtures thereof, which partically pyrolyzed particles have: (a) at least 85% by weight of carbon, (b) multimodal pore distribution with macropores ranging in size from about 50 .ANG. to about 100,000 .ANG. in average critical dimension and with macropores ranging in size from about 4 .ANG. to about 50 .ANG. in average critical dimension, and (c) a carbon to hydrogen atom ratio of between about 1.5:1 and about 20:1. A process for producing the aforesaid partically pyrolyzed particles is also described. This process comprises thermally degrading at a temperature between about 300.degree.C and about 900.degree.C, preferably between about 400.degree.C and 800.degree.C, and in an inert gaseous atmosphere optionally containing an activating gas, a macroporous synthetic polymer containing a carbon-fixing moiety and derived from one or more ethylenically unsaturated monomers or monomers which may be condensed to yield macroporous polymers, or mixtures thereof, for a time sufficient to drive off sufficient volatile components of the synthetic polymer to yield particles having the characteristics described above; and thereafter cooling said particles under said inert atmosphere to a temperature below that which would cause oxidation in air. The pyrolyzed particles so produced are particularly useful as adsorbents in both gaseous and liquid media to remove impurities therefrom. |
