Process for the production of cellulose-silicate products

• US 4,328,136 A
• Filed: 06/22/1981
• Issued: 05/04/1982
• Est. Priority Date: 12/30/1980
• Status: Expired due to Fees

• Current Assignee: David H. Blount
• Original Assignee: David H. Blount
• Inventors: Blount, David H.
• Primary Examiner(s): Foelak, Morton
• Application Number:
  US06/275,827
• Time in Patent Office: 316 Days
• Field of Search: 106/162, 106/193 R, 106/287.1, 106/287.12, 106/287.34, 260/9, 260/17 R, 260/17.4 BB, 260/13, 260/14, 260/17.3, 260/17.4 R, 260/37 SI, 260/37 N, 528/44
• US Class Current: 523/204
• CPC Class Codes: C04B 18/26 Wood, e.g. sawdust, wood shavings
• CPC Class Codes: C04B 22/14 containing sulfur in the anion, e.g. sulfides
• CPC Class Codes: C04B 28/26 Silicates of the alkali metals
• CPC Class Codes: C08G 18/6484 Polysaccharides and derivatives thereof
• CPC Class Codes: C08G 18/6492 Lignin containing materials; Wood resins; Wood tars; Derivatives thereof
• CPC Class Codes: Y02W 30/91 Use of waste materials as fillers for mortars or concrete

Abstract

A process for impregnating and reacting cellulose particles with oxidated silicon acid to produce lignin-cellulose-silicate and/or cellulose-silicate products impregnated with hydrated silica.

Claims

1. The process for the production of lignin-cellulose silicate products containing impregnated hydrated silica and binder by mixing and reacting the following components:

(a) 1 to 100 parts by weight of an oxidated silicate compound, selected from the group of oxidized alkaline earth metal silicate, oxidized mono alkali metal silicic acid, oxidized mono alkaline earth metal silicic acid, oxidized silicic acid and mixtures thereof;

(b) 50 parts by weight of plant cellulose particles, selected from the group consisting of cotton, wood cellulose, regenerated cellulose, sulfate cellulose produced by the Kraft process, sulfite cellulose, mechanical pulp cellulose, vegetable cellulose, cellulose esters and semichemical cellulose;

(c) a salt-forming compound selected from the group consisting of hydrochloric and sulfuric acid and in an amount wherein the mixture of components (a), (b) and (c) has a pH of 1.5 to 5 after the reaction is complete;

(d) then binder is added to the lignin-cellulose-silicate product impregnated with hydrated silica.

2. The process of claim 1 wherein water is added to the oxidated silicate compound, selected from the group consisting of sodium silicate and potassium silicate.

3. The process of claim 1 wherein the oxidized silicate compound is an aqueous oxidized alkali metal solution, selected from the group consisting of sodium silicate potassium silicate.

4. The process of claim 1 wherein the oxidated silicate compound is an aqueous oxidized sodium silicate solution which is mixed with the plant cellulose particles, then added to the salt-forming compound until the pH is between 1.5 and 5, thereby producing a cellulose-silicate product containing impregnated hydrated silica;

the salt, water and salt-forming compound and excess binder are filtered off.

5. The process of claim 1 wherein the oxidated silicate compound is an aqueous solution of oxidized silicic acid and sodium hydroxide in the ratio of 4 to 8 parts by weight of oxidized silicic acid to 1 part by weight of sodium hydroxide, containing 1% to 10% by weight of solids, which is then added to 5% to 40% of sulfuric acid to produce an acidic solution of oxidated silicic acid with a concentration of 2% to 20% calculated as SiO₂ and a pH of 1.5 to 5;

then the cellulose particles are mixed with the solution, thereby producing a lignin-cellulose-silicate product impregnated with hydrated silica;

the cellulose-silicate product is recovered by filtration;

then a binder is added to the lignin-cellulose-silicate product impregnated with hydrated silica.

6. The product of claim 1 wherein the components are mixed simultaneously and the resulting mixture has a pH of from 1.5 to 5.

7. The product produced by the process of claim 1.

8. The process of claim 1 wherein the cellulose particles are sodium cellulose xanthate particles which have been dissolved in an aqueous sodium hydroxide solution.

9. The process of claim 1 wherein the cellulose particles are first treated with an ammonial copper solution to form a viscous solution.

10. The process of claim 1 wherein the cellulose particles are first dissolved in a 70% to 80% sulfuric acid solution.

11. The process of claim 1 wherein the oxidized silicate compound is an aqueous solution of oxidized alkali metal silicate selected from the group consisting of sodium silicate and potassium silicate and is first reacted with the plant cellulose particles by mixing and agitating at a temperature up to the boiling point of the solution for 1 to 12 hours, thereby producing an alkali metal lignin-cellulose polymer product.

12. The product produced by the process of claim 11.

13. The product produced by the process of claim 8.

14. The product produced by the process of claim 9.

15. The product produced by the process of claim 10.

16. The process of claim 1 wherein the binder is selected from the group consisting of plastic binders, elastomer binders, plastic silicate binders, water-binding agents, alkali metal silicates, alkali metal aluminates and mixtures thereof.

17. The process of claim 16 wherein the plastic binder is selected from the group consisting of polyvinylacetates, polyacrylates, polyvinylchlorides and copolymers, polyacrylonitrile polymers, polyesters, polyamide polymers, epihalohydrin polyamine resins, phenoplast resins, aminoplast resins, epoxy resins and mixtures thereof.

18. The process of claim 16 wherein the elastomer binder is selected from the group consisting of polybutadienes, styrene-butadiene copolymers, polychloroprenes and mixtures thereof.

19. The process of claim 16 wherein the plastic silicate binder is selected from the group consisting of epihalohydrin polyamine silicate resins, allyl halide epihalohydrin polyamine silicate resins, aminoplast silicate resins, phenoplast silicate resins, polyester silicate resins, epoxy silicate resins, polyamide silicate resins, ethylenepolysulfide silicate polymer, polyacrylate silicate polymers, polyvinyl silicate polymers and mixtures thereof.

20. The process of claim 1 wherein a buffering acid having a pK between 2 and 6 which is added to the salt-forming compound is selected from the group consisting of polycarboxylic acids, complex acids of acidic sulphites and acetones, ketones and aldehydes, and mixtures thereof.