VERFAHREN ZUM ENTTINTEN VON ABFALLPAPIER

摘要

1417354 Pulping wood chips G A F CORP 9 Oct 1973 [1 Nov 1972 20 July 1973] 22014/75 Divided out of 1417353 Heading D2W Pulp is prepared by cooking wood chips at elevated temperature and pressure with a cooking liquor containing an N-alkyl or N-cycloalkyl lactam in an amount within the range of from- 0.01 % to 10% by wt. based on the total wt. of the cooking liquor. The latter may be alkaline e.g. a Kraft, or soda cooking liquor, or acidic. Preferred lactams are N-cyclohexyl pyrrolidone N-t-octyl pyrrolidone and N-t-butyl pyrrolidone. The invention also comprises an aqueous, alkaline cooking liquor containing sodium hydroxide and an N-alkyl or N-cycloalkyl lactam in an amount within the range specified above. The liquor may also contain sodium sulphide.