| 摘要 |
A process for the deinking of waste newsprint, which comprises steps for (a) converting the waste newsprint to a pulp, (b) contacting and agitating the pulp in an aqueous medium containing a deinking agent comprising a mixture of (i) a water-soluble C9 to C16 alkanol ethoxylate component having an average of about 6.5 to 20 oxyethylene units per ethoxylate molecule and (ii) an oil-soluble C9 to C16 alkanol ethoxylate component having an average of about 0.5 to 3.5 oxyethylene units per ethoxylate molecule, said mixture containing the respective components (i) and (ii) in a relative weight ratio in the range from about 2:1 to 1:3, and said mixture being present in said aqueous medium in an amount between about 0.1 and 5 percent by weight based on the dry weight of the newsprint fiber, and (c) recovering deinked pulp from the aqueous medium. The invention offers high performance in the removal of ink from pulp fibers and substantially eliminates the foaming of aqueous surfactant solution. Foaming has been recognized as a problem in conventional deinking processes employing deinking agents containing alcohol ethoxylate surfactants.
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