| 摘要 |
A solid methyl cellulose desiccant wherein from about 0.6 to 1.8, preferably 0.9 to 1.5 of the available hydroxyl groups of the anhydroglucose units of the cellulose entity have been replaced by methyl, or methyl and hydroxy alkyl or carboxy alkyl groups, if any, containing from 2 to about 4 carbon atoms, e.g. hydroxy ethyl, hydroxy propyl, carboxyl methyl and the like. In the solid methyl cellulose desiccant, at least one of the substituting groups must be methyl, with the remainder of the substituting groups, if any, hydroxy alkyl or carboxy alkyl, or both; preferably carboxy methyl, if any. At least one-half of the substituting groups are methyl, and preferably at least two-thirds of the substituting groups are methyl; the balance of the substituting groups, if any, being hydroxy alkyl or carboxy alkyl groups. Methyl cellulose of this character can be contacted with a water-containing stream at a temperature below which it will have great affinity for and will absorb significant amounts of water; and conversely above this temperature the methyl cellulose will not only lose this affinity but in addition may give up a large portion of any water it had previously absorbed.
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