Process for digesting cellulose-containing material with gaseous hydrogen fluoride

Abstract From the Canadian patent

Abstract of the disclosure:, The semi-continuous process according to the invention for digesting cellulose-containing material (substrate) with gaseous hydrogen fluoride comprises sorption and subsequent desorption of HF in a total of n steps. The substrate is divided into n batches in n reactors (1a, 1b, 1c, ...); each batch passes through the n process steps in one reactor (1a ...). Initially, sorption is carried out in the first to the ?th step by the action of HF-inert gas mixtures, having an HF concentration which increases from sorption step to sorption step, at a temperature above the boiling point of HF. subsequently desorption is brought about in the ( ?+1)th to nth step by …