Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Publication of BE530746ApublicationCriticalpatent/BE530746A/xx
D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
D21C3/00—Pulping cellulose-containing materials
D21C3/04—Pulping cellulose-containing materials with acids, acid salts or acid anhydrides
D21C3/06—Pulping cellulose-containing materials with acids, acid salts or acid anhydrides sulfur dioxide; sulfurous acid; bisulfites sulfites
