1
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Diaz-Baca JA, Fatehi P. Production and characterization of starch-lignin based materials: A review. Biotechnol Adv 2024; 70:108281. [PMID: 37956796 DOI: 10.1016/j.biotechadv.2023.108281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 10/27/2023] [Accepted: 11/05/2023] [Indexed: 11/15/2023]
Abstract
In their pristine state, starch and lignin are abundant and inexpensive natural polymers frequently considered green alternatives to oil-based and synthetic polymers. Despite their availability and owing to their physicochemical properties; starch and lignin are not often utilized in their pristine forms for high-performance applications. Generally, chemical and physical modifications transform them into starch- and lignin-based materials with broadened properties and functionality. In the last decade, the combination of starch and lignin for producing reinforced materials has gained significant attention. The reinforcing of starch matrices with lignin has received primary focus because of the enhanced water sensitivity, UV protection, and mechanical and thermal resistance that lignin introduces to starch-based materials. This review paper aims to assess starch-lignin materials' production and characterization technologies, highlighting their physicochemical properties, outcomes, challenges, and opportunities. First, this paper describes the current status, sources, and chemical modifications of lignin and starch. Next, the discussion is oriented toward starch-lignin materials and their production approaches, such as blends, composites, plasticized/crosslinked films, and coupled polymers. Special attention is given to the characterization methods of starch-lignin materials, focusing on their advantages, disadvantages, and expected outcomes. Finally, the challenges, opportunities, and future perspectives in developing starch-lignin materials, such as adhesives, coatings, films, and controlled delivery systems, are discussed.
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Affiliation(s)
- Jonathan A Diaz-Baca
- Green Processes Research Centre and Chemical Engineering Department, Lakehead University, 955 Oliver Road, Thunder Bay, ON P7B5E1, Canada
| | - Pedram Fatehi
- Green Processes Research Centre and Chemical Engineering Department, Lakehead University, 955 Oliver Road, Thunder Bay, ON P7B5E1, Canada.
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2
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Rodrigues TL, Pedroso PDC, de Freitas JHC, Carvalho ACP, Flores WH, Morais MM, da Rosa GS, de Almeida ARF. Obtaining of a rich-cellulose material from black wattle (Acacia mearnsii De Wild.) bark residues. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:113055-113067. [PMID: 37848795 DOI: 10.1007/s11356-023-30254-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Accepted: 09/26/2023] [Indexed: 10/19/2023]
Abstract
Black wattle (Acacia mearnsii De Wild.) barks are residues produced by tannin industries in huge quantities, which are normally discharged on environmental or used for energy production. Therefore, this study aimed to evaluate the use of black wattle bark residues as a raw material on obtaining of a rich-cellulose material by alkaline (MET1), acetosolv (MET2), and organosolv (MET3) procedures. The results obtained indicated that the alkaline methodology, followed by a bleaching step (MET1), promoted klason lignin and hemicellulose removals more efficiently. It was possible to observe that better results were achieved using NaOH concentration of 6% (wt%), at 65 °C for 2.5 h, presenting a yield of 63.24 ± 1.25%, and a reduction on klason lignin content of almost 90.45%. Regarding the bleaching step, it was possible to obtain a material free of non-cellulosic compounds with a yield of 78.28 ± 1.48%. Thermogravimetric analysis indicated the removal of lignin and hemicellulose as well as an increase in cellulose degradation temperature, due to changes in crystalline phases. According to X-ray diffraction (XRD), the procedures employed have led to an increase in crystallinity from 66.27 to 91.78% due to the removal of non-cellulosic compounds. Scanning electron microscopy (SEM) showed morphological alterations in accordance with the removal of non-cellulosic compounds.
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Affiliation(s)
- Tereza Longaray Rodrigues
- Graduate Program in Materials Science and Engineering, Federal University of Pampa, Bagé, RS, 96413-172, Brazil
| | | | | | | | - Wladimir Hernández Flores
- Graduate Program in Materials Science and Engineering, Federal University of Pampa, Bagé, RS, 96413-172, Brazil
| | | | - Gabriela Silveira da Rosa
- Graduate Program in Materials Science and Engineering, Federal University of Pampa, Bagé, RS, 96413-172, Brazil
- Chemical Engineering, Federal University of Pampa, Bagé, RS, 96413-172, Brazil
| | - André Ricardo Felkl de Almeida
- Graduate Program in Materials Science and Engineering, Federal University of Pampa, Bagé, RS, 96413-172, Brazil.
- Chemical Engineering, Federal University of Pampa, Bagé, RS, 96413-172, Brazil.
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3
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Monção M, Wretborn T, Rova U, Matsakas L, Christakopoulos P. Salicornia dolichostachya organosolv fractionation: towards establishing a halophyte biorefinery. RSC Adv 2022; 12:28599-28607. [PMID: 36320546 PMCID: PMC9540244 DOI: 10.1039/d2ra04432c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Accepted: 09/27/2022] [Indexed: 11/07/2022] Open
Abstract
Halophytes are a potential source of lignocellulosic material for biorefinery, as they can be grown in areas unsuitable for the cultivation of crops aimed at food production. To enable the viable use of halophytes in biorefineries, the present study investigated how different organosolv process parameters affected the fractionation of green pressed fibers of Salicornia dolichostachya. We produced pretreated solids characterized by up to 51.3% ± 1.7% cellulose, a significant increase from 25.6% ± 1.3% in untreated fibers. A delignification yield of as high as 60.7%, and hemicellulose removal of as high as 86.1% were also achieved in the current study. The obtained cellulose could be completely converted to glucose via enzymatic hydrolysis within 24 h. The lignin fractions obtained were of high purity, with sugar contamination of only 1.22% w/w and ashes below 1% w/w in most samples. Finally, up to 29.1% ± 0.4% hemicellulose was recovered as a separate product, whose proportion of oligomers to total sugars was 69.9% ± 3.0%. To the best of our knowledge, this is the first report in which Salicornia fibers are shown to be a suitable feedstock for organosolv biomass fractionation. These results expand the portfolio of biomass sources for biorefinery applications. An organosolv method was developed for the fractionation of fibers of a halophyte plant in a biorefinery approach. Salicornia dolichostachya was used as raw material allowing the production of cellulose, hemicellulose, and lignin fractions.![]()
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Affiliation(s)
- Maxwel Monção
- Department of Civil, Environmental and Natural Resources Engineering, Luleå Tekniska UniversitetSE-971 87LuleåSweden+46 (0) 920 493043
| | - Tobias Wretborn
- Department of Civil, Environmental and Natural Resources Engineering, Luleå Tekniska UniversitetSE-971 87LuleåSweden+46 (0) 920 493043
| | - Ulrika Rova
- Department of Civil, Environmental and Natural Resources Engineering, Luleå Tekniska UniversitetSE-971 87LuleåSweden+46 (0) 920 493043
| | - Leonidas Matsakas
- Department of Civil, Environmental and Natural Resources Engineering, Luleå Tekniska UniversitetSE-971 87LuleåSweden+46 (0) 920 493043
| | - Paul Christakopoulos
- Department of Civil, Environmental and Natural Resources Engineering, Luleå Tekniska UniversitetSE-971 87LuleåSweden+46 (0) 920 493043
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4
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Capecchi E, Tomaino E, Piccinino D, Kidibule PE, Fernández-Lobato M, Spinelli D, Pogni R, Cabado AG, Lago J, Saladino R. Nanoparticles of Lignins and Saccharides from Fishery Wastes as Sustainable UV-Shielding, Antioxidant, and Antimicrobial Biofillers. Biomacromolecules 2022; 23:3154-3164. [PMID: 35877659 DOI: 10.1021/acs.biomac.2c00236] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Lignin nanoparticles containing saccharides from fishery wastes were prepared as sustainable biofillers for advanced materials. Organosolv lignin and Kraft lignin were used as polyphenol components in association with chitosan and chitooligosaccharides. The chemophysical and biological activities of lignin/saccharide nanoparticles, such as UV-shielding, antioxidant, and antimicrobial activities, were found to be dependent on both molecular weight and deacetylation degree of saccharides, with the best performance being obtained in the presence of low-molecular-weight and highly deacetylated chitooligosaccharides. In addition, chitooligosaccharides showed a synergistic antioxidant effect with lignins, associated with antimicrobial activity against Escherichia coli (Gram-negative) and Staphylococcus aureus (Gram-positive).
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Affiliation(s)
- Eliana Capecchi
- Department of Ecology and Biology, University of Tuscia, 01100 Viterbo, Italy
| | - Elisabetta Tomaino
- Department of Ecology and Biology, University of Tuscia, 01100 Viterbo, Italy
| | - Davide Piccinino
- Department of Ecology and Biology, University of Tuscia, 01100 Viterbo, Italy
| | - Peter Elias Kidibule
- Department of Molecular Biology, Centre for Molecular Biology Severo Ochoa (CSIC-UAM), University Autonomous from Madrid, Nicolás Cabrera, 1, Madrid 28049, Spain
| | - Maria Fernández-Lobato
- Department of Molecular Biology, Centre for Molecular Biology Severo Ochoa (CSIC-UAM), University Autonomous from Madrid, Nicolás Cabrera, 1, Madrid 28049, Spain
| | - Daniele Spinelli
- Next Technology Tecnotessile, Via del Gelso 13, 59100 Prato, Italy
| | - Rebecca Pogni
- Department of Biotechnology, Chemistry and Pharmacy, University of Siena, Via A. Moro 2, 53100 Siena, Italy
| | - Ana Garcia Cabado
- Biotechnology and Health ANFACO-CECOPESCA, Ctra. Colexio Universitario, 16, 36310 Vigo, Spain
| | - Jorge Lago
- Biotechnology and Health ANFACO-CECOPESCA, Ctra. Colexio Universitario, 16, 36310 Vigo, Spain
| | - Raffaele Saladino
- Department of Ecology and Biology, University of Tuscia, 01100 Viterbo, Italy
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5
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Prochukhan N, O'Brien SA, Davó-Quiñonero A, Trubetskaya A, Cotter E, Selkirk A, Senthamaraikannan R, Ruether M, McCloskey D, Morris MA. Room Temperature Fabrication of Macroporous Lignin Membranes for the Scalable Production of Black Silicon. Biomacromolecules 2022; 23:2512-2521. [PMID: 35506692 PMCID: PMC9198978 DOI: 10.1021/acs.biomac.2c00228] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
![]()
Rising global demand
for biodegradable materials and green sources
of energy has brought attention to lignin. Herein, we report a method
for manufacturing standalone lignin membranes without additives for
the first time to date. We demonstrate a scalable method for macroporous
(∼100 to 200 nm pores) lignin membrane production using four
different organosolv lignin materials under a humid environment (>50%
relative humidity) at ambient temperatures (∼20 °C). A
range of different thicknesses is reported with densely porous films
observed to form if the membrane thickness is below 100 nm. The fabricated
membranes were readily used as a template for Ni2+ incorporation
to produce a nickel oxide membrane after UV/ozone treatment. The resultant
mask was etched via an inductively coupled plasma reactive ion etch
process, forming a silicon membrane and as a result yielding black
silicon (BSi) with a pore depth of >1 μm after 3 min with
reflectance
<3% in the visible light region. We anticipate that our lignin
membrane methodology can be readily applied to various processes ranging
from catalysis to sensing and adapted to large-scale manufacturing.
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Affiliation(s)
- Nadezda Prochukhan
- School of Chemistry, Trinity College Dublin, Dublin 2, Ireland.,Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN) and Advanced Materials and Bioengineering Research (AMBER) Research Centres, Trinity College Dublin, Dublin 2, Ireland.,BiOrbic, Bioeconomy SFI Research Centre, University College Dublin, Dublin 4, Ireland
| | - Stephen A O'Brien
- Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN) and Advanced Materials and Bioengineering Research (AMBER) Research Centres, Trinity College Dublin, Dublin 2, Ireland.,School of Physics, Trinity College Dublin, Dublin 2, Ireland
| | - Arantxa Davó-Quiñonero
- School of Chemistry, Trinity College Dublin, Dublin 2, Ireland.,Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN) and Advanced Materials and Bioengineering Research (AMBER) Research Centres, Trinity College Dublin, Dublin 2, Ireland
| | - Anna Trubetskaya
- Department of Bioproducts and Biosystems, School of Chemical Engineering, Aalto University, Espoo 00076, Finland
| | - Eoin Cotter
- Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN) and Advanced Materials and Bioengineering Research (AMBER) Research Centres, Trinity College Dublin, Dublin 2, Ireland.,School of Physics, Trinity College Dublin, Dublin 2, Ireland
| | - Andrew Selkirk
- School of Chemistry, Trinity College Dublin, Dublin 2, Ireland.,Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN) and Advanced Materials and Bioengineering Research (AMBER) Research Centres, Trinity College Dublin, Dublin 2, Ireland
| | - Ramsankar Senthamaraikannan
- School of Chemistry, Trinity College Dublin, Dublin 2, Ireland.,Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN) and Advanced Materials and Bioengineering Research (AMBER) Research Centres, Trinity College Dublin, Dublin 2, Ireland
| | - Manuel Ruether
- School of Chemistry, Trinity College Dublin, Dublin 2, Ireland
| | - David McCloskey
- Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN) and Advanced Materials and Bioengineering Research (AMBER) Research Centres, Trinity College Dublin, Dublin 2, Ireland.,School of Physics, Trinity College Dublin, Dublin 2, Ireland
| | - Michael A Morris
- School of Chemistry, Trinity College Dublin, Dublin 2, Ireland.,Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN) and Advanced Materials and Bioengineering Research (AMBER) Research Centres, Trinity College Dublin, Dublin 2, Ireland.,BiOrbic, Bioeconomy SFI Research Centre, University College Dublin, Dublin 4, Ireland
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6
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Kong J, Li L, Zeng Q, Long J, He H, Wang Y, Liu S, Li X. Production of 4-Ethylphenol from Lignin Depolymerization in a Novel Surfactant-Free Microemulsion Reactor. Ind Eng Chem Res 2021. [DOI: 10.1021/acs.iecr.1c03636] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Juanhua Kong
- School of Chemistry and Chemical Engineering, State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, China
| | - Lixia Li
- School of Chemistry and Chemical Engineering, State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, China
| | - Qiang Zeng
- School of Chemistry and Chemical Engineering, State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, China
| | - Jinxing Long
- School of Chemistry and Chemical Engineering, State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, China
| | - Hongyan He
- Beijing Key Laboratory of Ionic Liquids Clean Process, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
| | - Yingying Wang
- South China Advanced Institute for Soft Matter Science and Technology, South China University of Technology, Guangzhou 510640, China
| | - Sijie Liu
- School of Chemistry and Chemical Engineering, State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, China
| | - Xuehui Li
- School of Chemistry and Chemical Engineering, State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, China
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7
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Hrůzová K, Matsakas L, Rova U, Christakopoulos P. Organosolv fractionation of spruce bark using ethanol-water mixtures: Towards a novel bio-refinery concept. BIORESOURCE TECHNOLOGY 2021; 341:125855. [PMID: 34523546 DOI: 10.1016/j.biortech.2021.125855] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Revised: 08/23/2021] [Accepted: 08/25/2021] [Indexed: 06/13/2023]
Abstract
The aim of this study was to assess the effect of hot water extraction followed by organosolv pretreatment on the enzymatic hydrolysability of spruce bark biomass. To this end, samples were pretreated at five different temperatures in the presence or not of acid catalyst. The cellulose content of pretreated biomass reached 49.6% w/w. During the enzymatic hydrolysis trials with 3% w/w dry solids, the final hydrolysis yield reached up to 70.1%, which corresponded to the release of 7.8 g/L of glucose. Whereas, the final hydrolysis yield obtained during the high-gravity enzymatic hydrolysis reached up to 43.5%. The concentration of released glucose was in range of 33.3 - 40.0 g/L with a hemicellulose sugars in a range of 5.5 - 6.6 g/L. These values are suitable for downstream bioconversion processes and represent a significant improvement over existing steam pretreatment methods.
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Affiliation(s)
- Kateřina Hrůzová
- Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, SE-971 87 Luleå, Sweden
| | - Leonidas Matsakas
- Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, SE-971 87 Luleå, Sweden.
| | - Ulrika Rova
- Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, SE-971 87 Luleå, Sweden
| | - Paul Christakopoulos
- Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, SE-971 87 Luleå, Sweden
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8
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Sain S, Matsakas L, Rova U, Christakopoulos P, Öman T, Skrifvars M. Spruce Bark-Extracted Lignin and Tannin-Based Bioresin-Adhesives: Effect of Curing Temperatures on the Thermal Properties of the Resins. Molecules 2021; 26:molecules26123523. [PMID: 34207740 PMCID: PMC8230302 DOI: 10.3390/molecules26123523] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2021] [Revised: 05/28/2021] [Accepted: 06/03/2021] [Indexed: 11/16/2022] Open
Abstract
In this study, formaldehyde-free bioresin adhesives were synthesised from lignin and tannin, which were obtained from softwood bark. The extraction was done via organosolv treatment and hot water extraction, respectively. A non-volatile, non-toxic aldehyde, glyoxal, was used as a substitute for formaldehyde in order to modify the chemical structure of both the lignin and tannin. The glyoxal modification reaction was confirmed by ATR–FTIR spectroscopy. Three different resin formulations were prepared using modified lignin along with the modified tannin. The thermal properties of the modified lignin, tannin, and the bioresins were assessed by DSC and TGA. When the bioresins were cured at a high temperature (200 °C) by compression moulding, they exhibited higher thermal stability as well as an enhanced degree of cross-linking compared to the low temperature-cured bioresins. The thermal properties of the resins were strongly affected by the compositions of the resins as well as the curing temperatures.
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Affiliation(s)
- Sunanda Sain
- Swedish Centre for Resource Recovery, University of Borås, SE-501 90 Borås, Sweden;
| | - Leonidas Matsakas
- Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, SE-971 87 Luleå, Sweden; (L.M.); (U.R.); (P.C.)
| | - Ulrika Rova
- Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, SE-971 87 Luleå, Sweden; (L.M.); (U.R.); (P.C.)
| | - Paul Christakopoulos
- Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, SE-971 87 Luleå, Sweden; (L.M.); (U.R.); (P.C.)
| | - Tommy Öman
- Materials and Production, RISE Research Institutes of Sweden, SE-943 33 Öjebyn, Sweden;
| | - Mikael Skrifvars
- Swedish Centre for Resource Recovery, University of Borås, SE-501 90 Borås, Sweden;
- Correspondence: ; Tel.: +46-33-435-4497
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9
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Special Issue: Biochemical and Thermochemical Conversion Processes of Lignocellulosic Biomass Fractionated Streams. Processes (Basel) 2021. [DOI: 10.3390/pr9060969] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Global consumption of materials such as forest resources, fossil fuels, earth metals and minerals are expected to double in the next 30 years, while annual waste production is estimated to increase by approximately 70% by 2050 [...]
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10
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Yeardley A, Bagnato G, Sanna A. Effect of Ceria Addition to Na 2O-ZrO 2 Catalytic Mixtures on Lignin Waste Ex-Situ Pyrolysis. Molecules 2021; 26:molecules26040827. [PMID: 33562554 PMCID: PMC7915913 DOI: 10.3390/molecules26040827] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 02/01/2021] [Accepted: 02/02/2021] [Indexed: 11/22/2022] Open
Abstract
Waste lignin is a potential source of renewable fuels and other chemical precursors under catalytic pyrolysis. For this purpose, four mixed metal oxide catalytic mixtures (Cat) derived from Na2CO3, CeO2 and ZrO2 were synthesised in varying compositions and utilised in a fixed bed reactor for catalytic vapour upgrading of Etek lignin pyrolysis products at 600 °C. The catalytic mixtures were analysed and characterised using XRD analysis, whilst pyrolysis products were analysed for distribution of products using FTIR, GC-MS and EA. Substantial phenolic content (20 wt%) was obtained when using equimolar catalytic mixture A (Cat_A), however the majority of these phenols were guaiacol derivatives, suggesting the catalytic mixture employed did not favour deep demethoxylation. Despite this, addition of 40–50% ceria to NaZrO2 resulted in a remarkable reduction of coke to 4 wt%, compared to ~9 wt% of NaZrO2. CeO2 content higher than 50% favoured the increase in conversion of the holo-cellulose fraction, enriching the bio-oil in aldehydes, ketones and cyclopentanones. Of the catalytic mixtures studied, equimolar metal oxides content (Cat_A) appears to showcase the optimal characteristics for phenolics production and coking reduction.
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Affiliation(s)
- Adam Yeardley
- Advanced Biofuels Lab, Institute of Mechanical, Process and Energy Engineering, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, UK;
| | - Giuseppe Bagnato
- School of Chemistry and Chemical Engineering, Queen’s University Belfast, David Keir Building, 39-123 Stranmillis Rd, Belfast BT9 5AG, UK;
| | - Aimaro Sanna
- Advanced Biofuels Lab, Institute of Mechanical, Process and Energy Engineering, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, UK;
- Correspondence:
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