ES314525A1 - Procedure for sacrification of the wood hemicellulose or other starting materials by percolation at pressure with diluid acids, as well as for the further processing of the sacral solutions obtained and from the residue, comp (Machine-translation by Google Translate, not legally binding) - Google Patents

Abstract

Process of saccharification of wood hemicellulose or other starting materials by pressure percolation with dilute acids, as well as for the subsequent treatment of the saccharine solutions obtained and of the residue composed essentially of cellulose and lignin, characterized in that the hydrolysis of the Hemicellulose is performed in at least two consecutive periods, each consisting of the following measures: a) .- Addition of a so-called dilute acid reactant charge with a concentration of hydrogen ions corresponding to 1 - 1.5% H2SO4 and at a temperature of about 90 to 100º C, to the preheated starting material at least up to about 100º C, until its saturation with adherent liquid. b) Heating the charge of material saturated with acidic liquid according to point a) up to the desired reaction temperature of 120 to 145º C, preferably 135 to 140º C, measured at the top of the percolator, keeping at this temperature for 15 minutes. 60 minutes. c) Washing of the sugar formed according to point b) with a series of washing loads of about 90 to 100º C, consisting partly of washed-out portions of a previous percolation with decreasing sugar concentration in order, and finally in water, at reduced or decreasing temperatures, in which case the portion (s) removed from the first washing charge (s) of the first period with the highest concentration of sugar are completely transformed into final products, and the remaining portions removed are stored for re-use as wash loads in another period of the next percolation, and because the residue of these periods that essentially contains cellulose and lignin is treated. d) .- Under hydrolysis of the main quantity of cellulose in several periods more analogously to conditions a) to c), but due to higher concentration of acid and/or higher heating temperatures and/or reaction times of the reactant charges under much more refined reaction conditions, where the first relatively concentrated dextrose removed portions obtained according to point c) are similarly finished transforming into final products, and the remaining eliminated portions obtained in c) are retained for reuse as charges of washing in another period or in the next percolation and a residue composed essentially of lignin is obtained, or e) .- to obtain alpha cellulose is subjected to an alkaline wash of lignin already known. (Machine-translation by Google Translate, not legally binding)