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Ammonia-ketone pulping process

  • US 3,951,734 A
  • Filed: 10/11/1974
  • Issued: 04/20/1976
  • Est. Priority Date: 10/11/1974
  • Status: Expired due to Term
First Claim
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1. A pulping process comprising the steps of:

  • mixing cellulosic raw materials with an aqueous pulping liquor containing ammonia and one or more ketones;

    digesting said cellulosic raw material in said liquor at a temperature of 170°

    C to 220°

    C and for a time of from 10 to 300 minutes with the ratio of 2 to 20 pounds pulping liquor to 1 pound oven-dried cellulosic raw material, the ammonia concentration and the ketone concentration being from 5 to 22% and 15 to 70% by weight, respectively, of the total liquor;

    cooling the mixture;

    separating the pulping liquor from the digested cellulosic raw material.

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