DE-ESTERIFICATION OF BIOMASS PRIOR TO AMMONIA PRETREATMENT AND SYSTEMS AND PRODUCTS RELATED THERETO

• US 20190010295A1
• Filed: 07/06/2018
• Published: 01/10/2019
• Est. Priority Date: 07/07/2017
• Status: Active Grant

• Current Assignee: The Board of Trustees of Michigan State University (Michigan State University)
• Original Assignee: The Board of Trustees of Michigan State University (Michigan State University)
• Inventors: Balan, Venkatesh, Sousa, Leonardo da Costa
• Granted Patent: US 11,440,999 B2
• Time in Patent Office: Days
• CPC Class Codes: A23K 10/37 from waste material from hydrolysates of wood or straw A23K10/32; from molasses A23K10/33
• CPC Class Codes: A23K 10/38 from distillers' or brewers' waste
• CPC Class Codes: B01J 19/0006 Controlling or regulating processes controlling or regulating in general G05
• CPC Class Codes: C08H 8/00 Macromolecular compounds derived from lignocellulosic materials pretreatment thereof B27N

Abstract

A method is provided for pretreating cellulosic or lignocellulosic biomass comprising de-esterifying the biomass with an alkali treatment to produce de-esterified biomass; and pretreating the de-esterified biomass with ammonia to produce de-esterified ammonia pretreated biomass. In various embodiments, the de-esterified ammonia pretreated biomass has an amide concentration ranging from about 0.04 to about 25 mg/g biomass. In other embodiments, the amide concentration is no more than 0.04 mg/g biomass. Various ammonia pretreatment processes may be used, including liquid or gaseous ammonia pretreatments, including, but not limited to, liquid ammonium hydroxide pretreatments, various AFEX pretreatments, with or without biomass densification, and various cellulosic conversion pretreatments including “COBRA” pretreatments. Products (e.g., animal feed) and systems are also disclosed.

Claims

1. A method of pretreating biomass comprising:

de-esterifying the biomass with an alkali to produce de-esterified biomass; and

pretreating the de-esterified biomass with ammonia to produce de-esterified ammonia pretreated biomass.

2. The method of claim 1 wherein an amide concentration in the de-esterified ammonia pretreated biomass contains ranges from about 0.04 mg/g biomass to about 25 mg/g biomass.

3. The method of claim 2 wherein the amide concentration is substantially zero.

4. The method of claim 1 wherein the de-esterified biomass is neutralized with concentrated hydrochloric acid or concentrated sulfuric acid prior to the pretreating step.

5. The method of claim 1 wherein the alkali is Ca(OH)₂ (lime), KOH, NaOH, or a combination thereof.

6. The method of claim 1 wherein the biomass is densified biomass.

7. The method of claim 6 wherein the densified biomass is re-densified following the pretreating step to produce animal feed.

8. The method of claim 1 wherein the biomass is densified after the de-esterifying step to produce densified de-esterified biomass.

9. The method of claim 8 wherein the densified de-esterified biomass is re-densified following the pretreating step to produce animal feed.

10. The method of claim 1 wherein the biomass is densified after the pretreating step to produce densified de-esterified ammonia pretreated biomass.

11. The method of claim 1 wherein the pretreating step comprises a liquid ammonium hydroxide pretreatment or an ammonia fiber expansion (AFEX) pretreatment.

12. The method of claim 11 wherein the AFEX pretreatment is a liquid AFEX pretreatment, a gaseous AFEX pretreatment, or an extractive AFEX pretreatment.

13. The method of claim 1 wherein the biomass is brewer'"'"'s spent grains (BSG) or distiller'"'"'s dry grain DDGS.

14. The method of claim 1 wherein the biomass is lignocellulosic biomass.

15. The method of claim 14 wherein the lignocellulosic biomass is selected from corn stover, poplar, switchgrass, sugarcane bagasse, wheat straw, sorghum, energy cane, miscanthus, soybean meal, and combinations thereof.

16. The method of claim 14 wherein the pretreating step comprises a cellulosic conversion liquid ammonia pretreatment.

17. The method of claim 16 wherein the cellulosic conversion liquid ammonia pretreatment is a densified cellulosic conversion liquid ammonia pretreatment.

18. The method of claim 1 wherein the alkali is present in a concentration from 2% to about 8%.

19. The method of claim 1 wherein the alkali is present in a concentration of no more than 8%.

20. An animal feed comprising:

de-esterified ammonia pretreated biomass no more than 0.04 mg/g biomass of amides, wherein amide formation is limited by;

de-esterifying the biomass with an alkali treatment to produce de-esterified biomass; and

pretreating the de-esterified lignocellulosic biomass with ammonia to produce de-esterified ammonia pretreated biomass.

21. A system comprising:

a reactor for de-esterifying and ammonia pretreating biomass to produce de-esterified ammonia pretreated biomass containing no more than 0.04 mg/g biomass of amides; and

a system controller connected to the reactor.