Method for preparing sugar, bioethanol or microbial metabolite from lignocellulosic biomass

Patent metadata

Field	Value
Publication number	US-10927388-B2
Application number	US-201816150760-A
Country	US
Kind code	B2
Filing date	Oct 3, 2018
Priority date	Jul 9, 2013
Publication date	Feb 23, 2021
Grant date	Feb 23, 2021

Abstract

The present invention relates to a method for preparing bioethanol from lignocellulosic biomass. The method of the present invention is capable of: minimizing the impurity content of an enzymatic saccharification raw material, by extracting biomass using hot water, before pretreatment, and removing extractable substances such as inorganic salts; suppressing, to the greatest extent, the production of overdecomposition products of sugar, by pretreating the biomass, from which the hot water extractable substances have been removed, in a condition for maximizing xylan yield; preparing fermentable sugar at a low cost, without washing a pretreated solid obtained from subsequent solid-liquid separation, but by only concentrating a sugar solution obtained after enzymatic saccharification, using a separation film; and preparing bioethanol therefrom in high yield.

First claim

What is claimed is:

1. A method for preparing a sugar solution, the method comprising the steps of:
modifying a polyamide nanofiltration membrane by dipping a polyamide nanofiltration membrane in an aqueous solution containing 0.5 to 3 wt % of sodium hypochlorite and 0.05 to 0.5 wt % of polyethylene glycol methacrylate (step 1); and
filtering an aqueous sugar solution obtained by hydrolyzing cellulosic biomass using the modified polyamide nanofiltration membrane to recover a refined sugar solution from the non-permeate side and remove fermentation inhibitors from the permeate side (step 2).

2. The method according to claim 1 , between the step 1) and the step 2), further comprising:
filtering the aqueous sugar solution obtained by hydrolyzing cellulosic biomass using a microfiltration membrane or ultrafiltration membrane to recover a sugar solution from the permeate side.

3. The method according to claim 1 , after the step 2), further comprising:
filtering the refined sugar solution using a reverse osmosis membrane to recover a refined sugar solution from the non-permeate side and remove fermentation inhibitors from the permeate side.

4. The method according to claim 1 , wherein the fermentation inhibitors are at least one selected from the group consisting of organic acids, furan compounds, and phenol compounds.

5. The method according to claim 1 , wherein the filtration at the step 2) is constant volume filtration.

6. The method according to claim 1 , wherein pH of the aqueous sugar solution at the step 2) is from 4 to 8.

7. The method according to claim 1 , wherein temperature of the aqueous sugar solution at the step 2) is from 15 to 40° C.

Assignees

• Korea Res Inst Chemical Tech

Inventors

• Yu Ju Hyun
• Jung Chan Duck
• Eom In Yong
• Lee Seung Hwan
• Hong Kyung Sik
• Kim In-Chul
• Jegal Jong Geon
• Song Bong Keun

Classifications

• C12P19/02 Primary

  Monosaccharides (2-ketogulonic acid C12P7/60) · CPC title

• C12P7/10

  substrate containing cellulosic material · CPC title

• C12P2201/00

  Pretreatment of cellulosic or lignocellulosic material for subsequent enzymatic treatment or hydrolysis · CPC title

• C07H1/06

  Separation; Purification · CPC title

• C12P19/14

  produced by the action of a carbohydrase {(EC 3.2.x)}, e.g. by alpha-amylase {, e.g. by cellulase, hemicellulase} · CPC title