Deep Eutectic Solvent Pretreatment for Cellulose Enrichment from Coffee Waste
Source abstract
Abstract
The treatment of coffee silverskin (CSS), a waste stream from the coffee industry, through deep eutectic solvents (DES) was studied. Choline chloride-based DES mixtures were checked by using a lactic acid (LA) hydrogen bond donor. The effect of time, temperature and biomass:DES ratio on the dissolution of lignin and hemicellulose was analyzed. Maximum hemicellulose reduction was from 28.15% to 3.37% at 60 °C and 1 h and maximum lignin reduction was from 33.1% to 20.03% at 90 °C and 5 h. Additionally, it was found that the optimum operating conditions obtained were 3 h, 120 °C and biomass:DES ratio (1:10), which led to 8.02%, 29.31% and 36.48% hemicellulose, lignin and cellulose content, respectively. Consequently, DES pretreatment can be considered a promising approach to obtain cellulose-enriched coffee silverskin solids under lower-temperature conditions than many conventional lignocellulosic biomass pretreatments. However, further downstream validation is required to assess their suitability for paper, textile, or food-packaging-related applications.
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Affiliations
Department of Chemistry and Process & Resources Engineering, Technical School of Industrial and Telecommunications Engineering, University of Cantabria, Av. Los Castros s/n Santander, 39005 Santander, Spain
References (55)
Show source-provided references
1. Spent Coffee Ground as Second-Generation Feedstuff for Dairy Cattle10.1007/s13399-020-00610-7 ↗
2. International Coffee Organization (2026). Improved Supply Outlook Weighing Down on the I-CIP, International Coffee Organization.
3. Study on the Antioxidant Properties of Robusta and Arabica Coffee Silverskin By-Product with Different Degrees of Grinding10.1016/j.fufo.2025.100885 ↗
4. Coffee By-Products in Topical Formulations: A Review10.1016/j.tifs.2021.02.064 ↗
5. Coffee Silverskin: Nontraditional Natural Antioxidant for the Meat Industry10.1016/j.afres.2025.101185 ↗
6. Can Coffee Silverskin Be a Suitable Substrate for Biogas Production and Odour Impact Mitigation of Digestate?10.1016/j.jclepro.2026.147814 ↗
7. Boninsegna, M.A., De Bruno, A., Giacondino, C., Piscopo, A., Crea, G., Chinè, V., and Poiana, M. (2025). Use of Coffee Roasting By-Products (Coffee Silverskin) as Natural Preservative for Fresh-Cut Fennel Slices. Foods, 14.10.3390/foods14091493 ↗
8. Eckhardt, S., Franke, H., Schwarz, S., and Lachenmeier, D.W. (2022). Risk Assessment of Coffee Cherry (Cascara) Fruit Products for Flour Replacement and Other Alternative Food Uses. Molecules, 27.10.3390/molecules27238435 ↗
9. A Study on Chemical Constituents and Sugars Extraction from Spent Coffee Grounds10.1016/j.carbpol.2010.07.063 ↗
10. Pereira, A.P., Woodman, T.J., Brahmbhatt, P., and Chuck, C.J. (2019). The Optimized Production of 5-(Hydroxymethyl)Furfural and Related Products from Spent Coffee Grounds. Appl. Sci., 9.10.3390/app9163369 ↗
11. Production of Molecular Weight Fractionated Hemicelluloses Hydrolyzates from Spent Coffee Grounds Combining Hydrothermal Extraction and a Multistep Ultrafiltration/Diafiltration10.1016/j.biortech.2019.121940 ↗
12. Evolution of Lignocellulosic Macrocomponents in the Wastewater Streams of a Sulfite Pulp Mill: A Preliminary Biorefining Approach10.1155/2015/102534 ↗
13. Co-Production of Crystalline Cellulose and Biofuel from Low-Lignin Biomass10.1007/s12155-025-10947-4 ↗
14. Emerging Pretreatment Technologies for Agricultural Wastes in Single Cell Protein Production10.1016/j.afres.2026.101722 ↗
15. Llano, T., Quijorna, N., and Coz, A. (2017). Detoxification of a Lignocellulosic Waste from a Pulp Mill to Enhance Its Fermentation Prospects. Energies, 10.10.3390/en10030348 ↗
16. Di Techno-Economic Evaluation of Integrated Fractionation of Cocoa Pod Husk Biomass Using Microwave Assisted-Green Deep Eutectic Solvent Pretreatment10.1016/j.biombioe.2026.109083 ↗
17. Recent Advancements in Deep Eutectic Solvent (DES) Pretreatment: Applications, Mechanisms, and Integration with Emerging Technologies for Biorefinery10.1016/j.indcrop.2025.121028 ↗
18. Acidic Deep Eutectic Solvents for Pretreatment of Corn Stalk Biomass: Effects on Cellulose and Lignin Structure and Extraction Efficiency10.1016/j.carres.2026.109928 ↗
19. Use of Green Solvents as Pre-Treatment of Dissolving Pulp to Decrease CS2 Consumption from Viscose Production10.1007/s10570-020-03465-3 ↗
20. Deep Eutectic Solvent-Mediated Delignification of Corn Stover for Improved Fermentable Sugar Yield and Bioethanol Production10.1016/j.fuel.2025.135457 ↗
21. Purification Process Coupling Membrane Filtration and Adsorption for Deep Eutectic Solvent (DES) Recycling after Lignin Extraction10.1016/j.biortech.2026.134295 ↗
22. Valorization of Waste Tomato Leaves with Natural Deep Eutectic Solvents10.1016/j.foodchem.2025.142884 ↗
23. Enhancing Lignocellulosic Biomass Pretreatment with Choline Chloride-Based Deep Eutectic Solvents10.1016/j.jece.2025.117087 ↗
24. Eco-friendly simultaneous extraction of pectins and phenolics from passion fruit (Passiflora edulis Sims) peel: Process optimization, physicochemical properties, and antioxidant activity10.1016/j.ijbiomac.2023.125229 ↗
25. Efficient Removal of Lignin in Tobacco Stems with Choline Chloride-Based Deep Eutectic Solvents10.1016/j.indcrop.2025.120634 ↗
26. Fermentable Sugar Production from a Coffee Processing By-Product after Deep Eutectic Solvent Pretreatment10.1016/j.biteb.2018.10.012 ↗
27. Optimization and Kinetics Modeling of Phenolics Extraction from Coffee Silverskin in Deep Eutectic Solvent Using Ultrasound-Assisted Extraction10.1016/j.heliyon.2023.e17942 ↗
28. Green Extraction of Coffee Silverskin Bioactives Using Deep Eutectic Solvents and Their Cosmetic Application10.1002/slct.202505034 ↗
29. Selected Grass Plants as Biomass Fuels and Raw Materials for Papermaking, Part II. Pulp and Paper Properties
30. Impact of the Chemical Composition of Pinus Radiata on Its Physical and Mechanical Properties Thermo-Hygromechanical Densification10.15376/biores.13.2.2268-2282 ↗
31. Mineralogical Characterization of Chemically Isolated Ingredients from Biomass10.1016/j.enconman.2013.09.024 ↗
32. Chemical Composition of Four Cultivated Tropical Bamboo in Genus Gigantochloa
33. Physicochemical and Thermal Characteristics of Choline Chloride-Based Deep Eutectic Solvents10.1016/j.chemosphere.2023.139485 ↗
34. Rapid Determination of Cellulose in Plantation Eucalypt Woods to Predict Kraft Pulp Yields
35. New Natural and Renewable Low Transition Temperature Mixtures (LTTMs): Screening as Solvents for Lignocellulosic Biomass Processing10.1039/C2GC35660K ↗
36. Methods for Pretreatment of Lignocellulosic Biomass for Efficient Hydrolysis and Biofuel Production10.1021/ie801542g ↗
37. Optimizing Corncob Pretreatment with Eco-Friendly Deep Eutectic Solvents to Enhance Lignin Extraction and Cellulose-to-Glucose Conversion10.1016/j.ijbiomac.2024.137432 ↗
38. Selective Degradation of Hemicellulose and Lignin for Improving Enzymolysis Efficiency via Pretreatment Using Deep Eutectic Solvents10.1016/j.biortech.2023.128937 ↗
39. Extraction and Modification of Hemicellulose from Lignocellulosic Biomass: A Review10.1515/gps-2021-0065 ↗
40. Priority Dissolution of Hemicellulose and Its Subsequent-Added Utilization along with High Activity Lignin10.15376/biores.21.2.2767-2770 ↗
41. Yao, Z., Chong, G., and Guo, H. (2024). Deep Eutectic Solvent Pretreatment and Green Separation of Lignocellulose. Appl. Sci., 14.10.3390/app14177662 ↗
42. Deep Eutectic Solvents as Pretreatment to Increase Fock’s Reactivity under Optimum Conditions10.1007/s10570-023-05628-4 ↗
43. Przypis, M., Wawoczny, A., and Gillner, D. (2023). Biomass and Cellulose Dissolution—The Important Issue in Renewable Materials Treatment. Appl. Sci., 13.10.3390/app13021055 ↗
44. Suriyachai, N., Khongchamnan, P., Laosiripojana, N., Kreetachat, T., Wongcharee, S., Sakulthaew, C., Chokejaroenrat, C., and Imman, S. (2024). Optimization of Cellulose Recovery Using Deep Eutectic Solvent Fractionation: A Response Surface Method Approach. Energies, 17.10.3390/en17174257 ↗
45. Deep Eutectic Solvents for Pretreatment of Lignocellulosic Biomass: Towards Circular Bioeconomy10.1016/j.rineng.2025.105188 ↗
46. Synergistic Role of Dewaxing and Deep Eutectic Solvent Pretreatment in Boosting Biohydrogen Production from Napier Grass10.1016/j.fuel.2026.138941 ↗
47. A ZnCl2–Lactic Acid Deep Eutectic Solvent Enables Efficient Cleavage of Bamboo Derived Condensed Lignin after Ultra Low Phytic Acid Hydrolysis for Xylooligosaccharide Production10.1016/j.ijbiomac.2026.150338 ↗
48. A Staged Biorefinery of Moso Bamboo to Produce Fermentable Sugar, Furfural, and High-Quality Lignin by Integrating a Solvent and a Catalyst Deep Eutectic Solvent10.1021/acssuschemeng.5c07633 ↗
49. Zhu, Y., Qi, B., Liang, X., Luo, J., and Wan, Y. (2021). Comparison of Corn Stover Pretreatments with Lewis Acid Catalyzed Choline Chloride, Glycerol and Choline Chloride-Glycerol Deep Eutectic Solvent. Polymers, 13.10.3390/polym13071170 ↗
50. Deep Eutectic Solvents Pretreatment of Agro-Industrial Food Waste10.1186/s13068-018-1034-y ↗
51. Co-Production of Furfural, Reducing Sugars and Xylooligosaccharides from Biomass through the Pretreatment with Mixture of Deep Eutectic Solvent Dodecyltrimethylammonium Bromide:Lactic Acid and γ-Valerolactone10.1016/j.scp.2025.102258 ↗
52. Cañadas, R., Duque, A., Bahíllo, A., Iglesias, R., and Manzanares, P. (2024). Pretreatment of Vine Shoot Biomass by Choline Chloride-Based Deep Eutectic Solvents to Promote Biomass Fractionation and Enhance Sugar Production. Bioengineering, 11.10.3390/bioengineering11090935 ↗
53. Natural Deep Eutectic Solvents for Lignocellulosic Biomass Pretreatment: Recent Developments, Challenges and Novel Opportunities10.1016/j.biotechadv.2018.08.009 ↗
54. Tunable and Functional Deep Eutectic Solvents for Lignocellulose Valorization10.1038/s41467-021-25117-1 ↗
55. Understanding the Role of Choline Chloride in Deep Eutectic Solvents Used for Biomass Delignification10.1021/acs.iecr.9b03588 ↗