Process for recovering hydrocarbons from hydrocarbon-containing biomass

• US 4,338,399 A
• Filed: 09/15/1980
• Issued: 07/06/1982
• Est. Priority Date: 09/15/1980
• Status: Expired due to Term

• Current Assignee: Standard Oil Company (BP PLC)
• Original Assignee: Standard Oil Company (BP PLC)
• Inventors: Price, Michael C., Shih, Chien-Cheng J., Weil, Thomas A., Dzadzic, Peter M.
• Primary Examiner(s): Wiseman, Thomas G.
• Application Number:
  US06/187,492
• Time in Patent Office: 659 Days
• Field of Search: 435/99, 435/105, 435/166-171, 435/262, 435/267, 435/271, 435/276, 435/813, 435/819, 426/7, 426/49, 426/50, 426/52
• US Class Current: 435/99
• CPC Class Codes: C12P 19/14 produced by the action of a carbohydrase (EC 3.2.x), e.g. by alpha-amylase , e.g. by cellulase, hemicellulase
• CPC Class Codes: C13K 1/04 Purifying
• CPC Class Codes: Y10S 435/813 Continuous fermentation

Abstract

A process for enzymatically converting whole plant biomass containing hydrocarbon-containing laticifers to soluble sugars and recovering hydrocarbons in increased yields which comprises hydrolyzing whole plant cellulosic material in the presence of enzymes, particularly cellulase, hemicellulase, and pectinase, to produce a hydrocarbon product and recovering from the hydrolysis products a major proportion of the cellulase, hemicellulase and pectinase enzymes for reuse. At least some portion of the required make-up of cellulase, hemicellulase and pectinase enzymes is produced in a two-stage operation wherein, in the first stage, a portion of the output sugar solution is used to grow enzyme secreting microorganisms selected from the group consisting of cellulase-secreting microorganisms, hemicellulase-secreting microorganisms, pectinase-secreting microorganisms, and mixtures thereof, and in the second stage, cellulase, hemicellulase and pectinase enzyme formation is induced in the microorganism-containing culture medium by the addition of an appropriate inducer such as biomass. The cellulase, hemicellulase and pectinase enzymes are then recycled for use in the hydrolysis reaction.

Claims

1. A process using enzymes for enzymatically converting whole plant biomass containing hydrocarbon-containing plants selected from the Euphorbiaceae, Apocynaceae, Asclepiadaceae, Compositae, Cactaceae and Pinaceae families and mixtures thereof to soluble sugars and recovering hydrocarbons from said plants in increased yields which comprises:

(a) hydrolyzing said whole plant biomass in the presence of enzymes selected from the group consisting of cellulase, hemicellulase and mixtures thereof under conditions which promote conversion of cellulose and hemicellulose to soluble sugars;

(b) removing a stream of hydrolysis products comprising a liquid sugar-containing phase, a liquid hydrocarbon-containing phase and a solid phase containing unhydrolyzed spent solids, all phases containing enzymes selected from the group consisting of cellulase and hemicellulase enzymes and mixtures thereof from the hydrolysis stage;

(c) separating liquid phases and solid phases of step (b);

(d) continuously adding a stream to step (a) of fresh said whole plant biomass to replenish said whole plant biomass converted to hydrolysis products;

(e) separating said liquid phases from step (c) thereby recovering said enzymes present and said hydrocarbons present;

(f) recovering a stream of product sugar solution and enzyme solution from step (e);

(g) sterilizing a sugar product stream from step (f) to serve as sterile growth medium for microorganisms;

(h) adding the recovered solids from step (c) to the hydrolysis stage;

(i) providing a stream of makeup enzymes selected from the group consisting of cellulase, hemicellulase and mixtures thereof for the hydrolysis steps by the steps including;

(1) in a first zone, growing in a suitable medium enzyme-synthesizing organisms selected from the group consisting of cellulase-synthesizing microorganisms, hemicellulase-synthesizing microorganisms and mixtures thereof, said microorganism-containing medium comprising minor portions of the product solutions;

(2) in a second zone contacting said microorganism-containing medium with an amount of cellulosic and hemicellulosic materials in an amount sufficient to induce formation of cellulase and hemicellulase under conditions substantially nonsupportive of growth of the cellulase and hemicellulase-secreting microorganisms.

2. The process of claim 1 wherein said whole plant biomass comprises hydrocarbon-containing plants selected from the group consisting of Euphorbia heterophylla, Euphorbia lathyrus, Euphorbia marginata, Euphorbia tirucalli, Ascelpias syriaca, Calotropis procera, Parthenium argentatum, Apocynum sibiricum and mixtures thereof.

3. The process of claim 1 wherein said enzymes comprise enzymes from the microorganisms Trichoderma viride, Aspergillus niger, Basidiomycetes poria, Trichoderma koningii, Fusarium soloni, Clostriduim thermocellum, Fusarium javanicum and mixtures thereof.

4. The process of claim 1 wherein the said process is a batch process.

5. The process of claim 1 wherein the said process is a continuous process.