| 摘要 |
A mixture of two components is fractionated by zone-melting in the presence of a separable substance which is a preferential solvent for one of the components. Materials which may be fractionated are microcrystalline wax, polypropylene, xylene, naphthalene, anthracene, phenanthrene, cresol, nitrophenol, nitrobenzoic acid, asphaltenes, vitamins, sucroses, dextroses, starches, and inorganic salts. Solvents are methyl ethyl ketone, acetone, ethylene dichloride, chloroform, carbon tetrachloride, ethylene glycol, butanol, butyl acetate, hexane, heptane, benzene, toluene, chlorobenzene and nitrobenzene (for wax); decalin (for polypropylene); phenol and benzophenone (for hydrocarbons); water and water-alcohol mixtures (for inorganic salts). A solvent-wax ratio of 6:1 to 3:1 may be employed, at least two molten zones may be passed simultaneously through the wax, the total number of molten zones may be 8-40, and the rate of passage of the molten zones may be 1-2 in./hr. A solvent-polypropylene ratio of 100:1 to 10:1 may be employed, the total number of molten zones may be at least 5, and the rate of passage of the molten zones may be 1-4 in./hr.
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