The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 26, 2021
Filed:
Feb. 20, 2017
Versalis S.p.a., San Donato Milanese, IT;
Fabio Sabbatini, Siena, IT;
Versalis S.p.A, San Donato Milanese, IT;
Abstract
It is disclosed a process to produce a fermentation product from a ligno-cellulosic feedstock hydrolyzate slurry which comprises water, water soluble glucose and xylose and water insoluble pretreated ligno-cellulosic feedstock. The process comprises at least two conversion step. A first conversion medium comprising a first portion of the ligno-cellulosic feedstock hydrolyzate slurry and a yeast capable to ferment glucose and xylose is first created, then the yeast is allowed to convert at least 50% of the glucose and less than 20% of the xylose of the first conversion medium to a first propagated yeast and a first portion of the fermentation product in a first conversion step having a first sugar-to-cells conversion ratio in a range of from 5% to 25%. A second conversion medium comprising at least a portion of the first propagated yeast and a second portion of the ligno-cellulosic feedstock hydrolyzate slurry is then created, then the yeast is allowed to convert at least a portion of the water soluble glucose and xylose in the second conversion medium to at least a second propagated yeast and a second portion of the fermentation product in a second conversion step having a second sugar-to-cells conversion ratio which is less than the first sugar-to-cells conversion ratio. Preferably, the first conversion step comprises at least a first phase which is an aerobic phase and a second phase which is an anaerobic phase.