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US-12623989-B2 - One-pot acid-catalyzed levulinic acid production from lignocellulosic biomass

US12623989B2US 12623989 B2US12623989 B2US 12623989B2US-12623989-B2

Abstract

Provided are methods for producing levulinic acid from hemp hurds. In some embodiments, the methods include dissolving hemp hurds in an ionic liquid medium to produce a cellulose-rich product; hydrolyzing cellulose present in the cellulose-rich product to produce a glucose-rich product; dehydrating glucose present in the glucose-rich product, and/or fructose resulting from isomerization of the glucose, to produce 5-hydroxymethyl furfural (HMF); and hydrolyzing the HMF to levulinic acid. Also provided are methods for producing levulinic acid from sugar sources generally, which can include providing a sugar source, wherein the sugar source is a hydrolysis product produced by hydrolyzing a cellulose-rich product generated from hemp hurds and/or a cellulase digestion product of softwood pre-treated with phosphoric acid (H 3 PO 4 ) or another acid; dehydrating the glucose present in the sugar source, and/or fructose resulting from isomerization of glucose present in the sugar source, to produce 5-hydroxymethyl furfural (HMF); and hydrolyzing the HMF to produce levulinic acid.

Inventors

  • Sarttrawut Tulaphol
  • Noppadon Sathitsuksanoh

Assignees

  • UNIVERSITY OF LOUISVILLE RESEARCH FOUNDATION, INC.

Dates

Publication Date
20260512
Application Date
20200416

Claims (15)

  1. 1 . A method for producing levulinic acid from lignocellulosic biomass of hemp hurds in a singular reaction vessel, the method comprising: (a) dissolving lignocellulosic biomass of hemp hurds in an amount of greater than 15 wt % in an ionic liquid medium to produce a cellulose-rich product in a reaction vessel; hydrolyzing cellulose present in the cellulose-rich product to produce a glucose-(b) rich product in the reaction vessel of a); (c) adding a phosphoric acid pretreated softwood into the vessel comprising the hydrolyzed product of b); (d) dehydrating glucose from the glucose-rich product of c), and/or dehydrating fructose from isomerization of the glucose of c), to produce 5-hydroxymethyl furfural (HMF) in the reaction vessel of a); and (e) hydrolyzing the HMF to levulinic acid in the reaction vessel of a).
  2. 2 . The method of claim 1 , wherein the ionic liquid medium comprises: a first component selected from the group consisting of 1-ethyl-3-methylimidazolium chloride ([C 2 C 1 im] Cl), 1-butyl-3-methylimidazolium chloride, 1-butyl-3-methylimidazolium hexafluorophosphate, 1-butyl-3-methylimidazolium acetate, 1-butyl-1-methylpyrrolidinium chloride, 1-butyl-3-methylimidazolium methylsulfate, N,N-dimethylethanolamonium hydrogen sulfate, N,N-dimethylethanolamonium acetate, N,N-dimethylethanolamonium glycolate, N,N-dimethylethanolammonium succinate, 1-ethyl-3-methylimidazolium acetate, 1-ethyl-3-methylimidazolium diethyl phosphate, 1-ethyl-3-methylimidazolium chloride, 1,3-dimethylimidazolium dimethyl phosphate, Cholinium glycinate, and Cholinium lysinate; and optionally a second component comprising an acid selected from the group consisting of hydrochloric acid, sulfuric acid, nitric acid, trifluoroacetic acid, and phosphoric acid.
  3. 3 . The method of claim 2 , wherein the second component is present in the ionic liquid medium at about a 0.1 acid/biomass weight ratio.
  4. 4 . The method of claim 2 , wherein the ionic liquid medium comprises [C 2 C 1 im]Cl and hydrochloric acid (HCl) at about a 0.1 HCl/Biomass weight ratio.
  5. 5 . The method of claim 1 , wherein the dissolving occurs at a temperature of about 140° C. to about 200° C. and/or for time of about 60 minutes to about 360 minutes.
  6. 6 . The method of claim 5 , wherein dissolving occurs at a temperature of about 150° C. to about 175° C. and/or for time of about 60 minutes to about 120 minutes.
  7. 7 . The method of claim 1 , wherein the hydrolyzing of the cellulose-rich product occurs at a temperature of about 95° C. to about 125° C. for about two hours or occurs at about 95° C. for about 1 hour to about 6 hours and provides a yield of at least 25% glucose or occurs at a temperature of about 95° C. to about 120° C. for about two hours or occurs at about 95° C. for at least 2 hours and provides a yield of at least 40% glucose.
  8. 8 . The method of claim 1 , wherein the hydrolyzing of the cellulose-rich product is performed in the presence of an acid catalyst, optionally wherein the acid catalyst comprises a Lewis acid.
  9. 9 . The method of claim 8 , wherein the Lewis acid is selected from CrCl 3 ·6H 2 O, AlCl 3 ·6H 2 O, ZrCl 4 , SnCl 2 , HfCl 4 , or SnCl 4 ·5H 2 O.
  10. 10 . The method of claim 1 , wherein the loading of lignocellulosic biomass of hemp hurds is about 15 wt % to about 25 wt %.
  11. 11 . The method of claim 1 , wherein the softwood is pretreated with phosphoric acid at a temperature from about 20° C. to about 180° C., or for about 0.1 hours to about 24 hours, or both the temperature and the time.
  12. 12 . The method of claim 1 , further comprising treating the phosphoric acid pre-treated softwood with an enzyme after the softwood is pretreated to hydrolyze the phosphoric acid pre-treated softwood, wherein the enzyme is cellulase, hemicellulase, β-glucosidase, or a combination thereof for a time and at a temperature sufficient to hydrolyze the glucan present in the pre-treated softwood.
  13. 13 . The method of claim 12 , wherein the enzyme combination is a mixture of cellulase and hemicellulase, optionally at a ratio of about 9:1 by weight.
  14. 14 . The method of claim 12 , wherein the enzyme combination comprises about 5 FPUs of cellulase and 10 units of β-glucosidase per gram of glucan, or the enzyme combination comprises about 15 FPUs of cellulase and 30 units of β-glucosidase per gram of glucan.
  15. 15 . A method for producing levulinic acid from lignocellulosic biomass of hemp hurds in a singular reaction vessel, the method comprising: (a) dissolving greater than 15 wt % of lignocellulosic biomass of hemp hurds in an ionic liquid medium at a temperature of about 140° C. to about 200° C. and/or for time of about 60 minutes to about 360 minutes to produce a cellulose-rich product in a reaction vessel; (b) hydrolyzing cellulose in the cellulose-rich product at a temperature of about 95° C. to about 125° C. for about 1 hour to about 6 hours in the presence of an acid catalyst, to produce a glucose-rich product in the reaction vessel of a); (c) adding a phosphoric acid pretreated softwood into the vessel comprising the hydrolyzed product of b); (d) dehydrating glucose from the glucose-rich product of c), and/or dehydrating fructose from isomerization of the glucose of c), to produce 5-hydroxymethyl furfural (HMF) in the reaction vessel of a); and (e) hydrolyzing the HMF to levulinic acid in the reaction vessel of a).

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application is a United States National Phase Entry of PCT International Patent Application No. PCT/US2020/028553, filed Apr. 16, 2020, incorporated herein by reference in its entirety and which claims the benefit of U.S. Provisional Patent Application Ser. No. 62/834,775, filed Apr. 16, 2019, the disclosure of which is incorporated herein by reference in its entirety. This application claims the benefit of U.S. Provisional Patent Application Ser. No. 62/834,775, filed Apr. 16, 2019, the disclosure of which is incorporated herein by reference in its entirety. GOVERNMENT INTEREST This invention was made with government support under Cooperative Agreement 1355438 awarded by the National Science Foundation. The government has certain rights in the invention. TECHNICAL FIELD The presently disclosed subject matter relates in some embodiments to methods for producing levulinic acid from hemp hurds and other sugar sources. In some embodiments, the presently disclosed subject matter relates to a method comprising dissolving hemp hurds in an ionic liquid medium to produce a cellulose-rich product; hydrolyzing cellulose present in the cellulose-rich product to produce a glucose-rich product; dehydrating glucose present in the glucose-rich product, and/or fructose resulting from isomerization of the glucose, to produce 5-hydroxymethyl furfural (HMF); and hydrolyzing the HMF to levulinic acid. BACKGROUND Increasing demand for transportation fuels and decreasing petroleum supplies have led to growing interest in using lignocellulose as a renewable feedstock for production of biofuels and chemicals. Cellulose-derived biofuels could supplement current transportation fuels, reduce air pollution, create jobs, and lessen the effects of petroleum-based fuels on climate. Industrial hemp, a variety of the Cannabis sativa L. and the same plant species as marijuana, has been of great interest because this fast-growing plant is a rich source of phytochemicals, fibers, and woody products (Ash, 1948; Ehrensing, 1998; Brady, 2003; Deitch, 2003; Ranalli & Venturi, 2004; Andre et al., 2016). For example, its outer shell (bast) can be used to make fibers for textiles (van der Werf & Turunen, 2008). Its flowering materials (e.g., flowers and leaves) are good sources for high-valued cannabidiol (CBD) oil (Leizer et al., 2000), which is used for pharmaceutical applications (Devinsky et al., 2014). Hemp oil can be extracted from seeds for cooking and cosmetics (Vogl et al., 2004). The by-product, hemp hurds (the soft inner core of the stalks and stems) is rich in cellulose and currently used in low-valued applications including garden mulch, lightweight paperboard, and acoustical ceiling (Asdrubali, 2006; Barberà et al., 2011). Although every part of the industrial hemp plant can be used to produce a variety of products, research on industrial hemp has been controversial in numerous parts of the world. This controversy is attributable to the misconception that hemp and marijuana are the same plant. This misunderstanding has significantly hindered hemp research. The Vote Hemp has estimated the retail hemp products sold in the United States in 2016 to be greater than $688 M, a ˜25% increase from 2015 that is projected to continue (VoteHemp, 2016). With the projected expansion of industrial hemp production, a large amount of under-utilized hemp hurds will become available. Previous methods to produce levulinic acid from plant biomass involved multi-step processes that employed expensive precious metal catalysts and harsh conditions (e.g., high pressure and temperature; see e.g. U.S. Patent Application Publication Nos. 2017/0190682, 2017/0183322, and 2015/0052806, and U.S. Pat. No. 9,346,730; each of which is incorporated by reference herein in its entirety). Furthermore, one of the major challenges in production of levulinic acid is the separation of intermediate products: glucose and HMF. Separation is one of the costly steps that hampers commercialization of the process. Thus, an integrated process that eliminates the separation of intermediate products would be desirable. The presently disclosed subject matter thus relates to successfully converted cellulosic biomass into levulinic acid in one pot with high yield and selectivity. Among other advantages, the presently disclosed one-pot strategy eliminates the costly separation steps. SUMMARY This Summary lists several embodiments of the presently disclosed subject matter, and in many cases lists variations and permutations of these embodiments of the presently disclosed subject matter. This Summary is merely exemplary of the numerous and varied embodiments. Mention of one or more representative features of a given embodiment is likewise exemplary. Such an embodiment can typically exist with or without the feature(s) mentioned; likewise, those features can be applied to other embodiments of the presently disclosed subject matter, whether listed in