Patent GB-499992-A (GB)
Title: Improvements in the manufacture of decolorizing and filtering agents
IPC: B01J20/20
Filed: 1937-10-26
Abstract: A decolourizing and filtering agent is obtained by reducing kieselguhr and woody materials separately to powders which are then mixed and carbonized, for example at 600 DEG  C., and then activated by means of steam or combustion gases, with or without added air, at a high temperature, e.g. 900 DEG  C., and this temperature is preferably not allowed to drop below the carbonization temperature. The woody materials include plant stalks, piths, husks, barks, corks, and woody seeds as fruit seeds, and tree wood, such as sawdust, particularly from coniferous trees.  The reduction of the woody material to powder is facilitated by first heating the wood until water is driven off and it darkens and becomes fragile.  The proportions used may vary in accordance with the filtering value and decolourizing power required and may vary from equal parts to 12 parts of raw wood and 1 part of kieselguhr.  Examples are given comparing the filtering value and decolourizing power of the product with those of kieselguhr, decolourizing carbon and a mixture of kieselguhr and decolourizing carbon, in respect of sugar solutions.ALSO:A decolourizing and filtering agent is obtained by reducing kieselguhr and woody materials separately to powders which are then mixed and carbonized, for example at 600 DEG  C., and then activated by means of steam or combustion gases, with or without added air at a high temperature, e.g. 900 DEG  C., and this temperature is preferably not allowed to drop below the carbonization temperature.  The woody materials include plant stalks, piths, husks, barks, corks and woody seeds as fruit seeds and tree wood, such as sawdust particularly from coniferous trees.  The reduction of the woody material to powder is facilitated by first heating the wood until water is driven off and it darkens and becomes fragile.  The proportions used may vary in accordance with the filtering value and decolourizing power required and may vary from equal parts to 12 parts of raw wood and 1 part of kieselguhr.  Examples are given comparing the filtering value and decolourizing power of the product with those of kieselguhr, decolourizing carbon and a mixture of kieselguhr and decolourizing carbon in respect of sugar solutions.ALSO:A decolourizing and filtering agent is obtained by reducing kieselguhr and woody materials separately to powders which are then mixed and carbonized, for example at 600 DEG  C., and then activated by means of steam or combustion gases, with or without added air at a high temperature, e.g. 900 DEG  C., and this temperature is preferably not allowed to drop below the carbonization temperature.  The woody materials include plant stalks, piths, husks, barks, corks and woody seeds, as fruit seeds, and tree wood, such as sawdust, particularly from coniferous trees.  The reduction of the woody material to powder is facilitated by first heating the wood until water is driven off and it darkens and becomes fragile.  The proportions used may vary in accordance with the filtering value and decolourizing power required and may vary from equal parts to 12 parts of raw wood and 1 part of kieselguhr.  Examples are given comparing the filtering value and decolourizing power of the product with those of kieselguhr, decolourizing carbon and a mixture of kieselguhr and decolourizing carbon in respect of sugar solutions.