Biopolymer Precursors Research Articles

Chemocatalytic Oxidation of 5‐hydroxymethylfurfural into 2,5‐furandicarboxylic Acid Over Nickel Cobalt Oxide

AbstractThe present study reports the synthesis, characterization, and application of NiCo bimetallic catalysts to produce 2,5‐furandicarboxylic acid (FDCA) via the oxidation of bio‐renewable 5‐hydroxymethylfurfural (HMF). FDCA is a biopolymer precursor and a potential replacement for terephthalic acid (TPA). The catalysts were synthesized via the co‐precipitation method in different molar ratios of NiCo, followed by calcination in a muffle furnace. As a result, the complete conversion of HMF and a maximum 84.89 % FDCA yield was measured at 50 °C in 50 minutes in the presence of NiCo(3 : 1) catalyst. In addition, effect reaction parameters, including catalyst amount, temperature, time, base, and oxidant amount on the FDCA yield, were studied, and the process was optimized. The NiCo(3 : 1) catalyst showed a negligible loss in activity for at least five cycles. The higher catalytic activity and stability are attributed to the synergistic effect of bimetallic catalysts, such as higher lattice oxygen. Accordingly, the catalyst was characterized using BET, XRD, H2‐TPR, CO2‐TPD, HR‐TEM, and XPS to correlate their properties and activity. The reaction products were analyzed quantitatively using HPLC and qualitatively using HR‐MS.

CO2 Reduction in a Bio Mass-Paired Systems for the Production of e-Chemicals

The electrification of chemical manufacturing is an important pathway toward reduced CO2 emissions. Direct electrochemical CO2 reduction can thereby become a key technology. CO2 electrolyzers produce cathodically platform chemicals as CO, format, ethanol or ethylene. The state-of-the-art anode process is the oxygen electro evolution which suffers from high over potentials and moderate valorization. An alternative is the anodic oxidation of biomass to valorized carbonaceous products, such as the oxidation of hydroxymethylfurfural (HMF) to the biopolymer precursor 2.5-furandicarboxylic acid (FDCA).In this work we report the design of electrolyzers flow cells with paired valorization of biomass and CO2. NiNC cathode GDEs are used for CO2 reduction to CO and NiFe-LDH anodes for the HMF oxidation in a zero-gap membrane electrolyzer flow cells. We used a bipolar membrane to separate and optimize either half-cell reactions. Inside the membrane, water is dissociated and the protons will neutralize carbonates on the cathode which is beneficial for a higher CO2 utilization and single pass. So, we can report close to 95% FE and 100% utilization efficiency towards CO.On the other hand, the hydroxide will stabilize the anode pH and enable PGM-free anodes compared to AEM CO2 electrolyzer. State-of-the-art HMF oxidation is a semi-batch setup, in which the HMF containing anolyte is recycled to complete HMF depletion and utilization. This design suffered from severe mass limitations. Therefore, we modified the semi-batch process into a continuous process and made tradeoffs between faradaic efficiency and utilization. As HMF is not stable in alkaline solutions we decided that a high utilization is beneficial because the intermediates are stable and could be recycled. We can report a single pass conversion of around 70 % towards FDCA at 200 mA cm-2 at a total utilization of 90%.Figure caption: Paired continuous HMF/CO2 electrolyzer with performance parameter. Figure 1

Exfoliated Layered Metal Oxide-Supported Ruthenium Catalysts for Base-Free Oxidation of 5-Hydroxymethylfurfural into a Renewable Bioplastic Precursor

2,5-Furandicarboxylic acid (FDCA) is a potential biopolymer precursor for polyethylene furanoate production. This study focused on synthesizing FDCA via catalytic oxidation of 5-hydroxymethylfurfural (HMF) over Ru-based catalysts supported on exfoliated MgAl-double oxides (LDO) for the first time in a homogeneous base-free system. Effects of the exfoliation solvent, preparation method, and Ru loading level on the physicochemical and catalytic properties of the resulting catalysts were investigated. The exfoliated LDO-supported Ru catalysts exhibited enhanced textural properties, RuOx dispersion, and basicity, resulting in better catalytic activity (at least 6 times higher FDCA yield) than conventional LDO-supported Ru catalysts in the conversion into FDCA. The Ru-based catalyst supported on an exfoliated LDO/carbon nanocomposite, Ru(3)/ESV-LDC, revealed the nearly complete HMF conversion (99.2%) at an FDCA selectivity of >98%. This was attributed to the synergistic effect derived from good RuOx dispersion, providing a high proportion of lattice oxygen for boosting surface oxygen mobility, and high basicity, in terms of both strength and number of basic sites. Moreover, Ru(3)/ESV-LDC exhibited good reusability without a significant loss of HMF conversion and FDCA yield, suggesting strong chemical robustness of RuOx species and a stable interaction between the active metal and support.

The Effect of Thermal Treatment on the Characteristics of Porous Ceramic-Based Natural Clay and Chitosan Biopolymer Precursors

This study was conducted to determine the role of thermal treatment on the crystallinity and pore characteristics of porous ceramic, which was prepared from natural clay (NC) and chitosan (CS) biopolymer using the gel casting method. CS was used as an environmentally friendly pore-forming agent. The applied temperature treatment was based on thermal analysis (TGA/DTA) results and followed a sintering temperature of 900 to 1100 °C. The results showed that at sintering temperatures from 900 to 1000 °C, the crystallinities of the ceramic decrease (from 76.06 to 74.06%) and the crystallite size decreases (from 35.71 to 34.47 nm) while the lattice strain increases (calculated from the Full Width at Half Maximum (β) of the diffraction peak). The highest porosity of ceramic occurred at a sintering temperature of 1000 °C of 37.82 ± 0.19, but the formation of heterogeneous microstructure was observed. The resulting pore size for all temperature treatments was almost mesoporous (19.1 Å). Based on the results obtained, it is emphasized that the sintering temperature can be used to adjust the porosity and microstructure of porous ceramics.

Non-Covalently Associated Streptavidin Multi-Arm Nanohubs Exhibit Mechanical and Thermal Stability in Cross-Linked Protein-Network Materials.

Constructing protein-network materials that exhibit physicochemical and mechanical properties of individual protein constituents requires molecular cross-linkers with specificity and stability. A well-known example involves specific chemical fusion of a four-arm polyethylene glycol (tetra-PEG) to desired proteins with secondary cross-linkers. However, it is necessary to investigate tetra-PEG-like biomolecular cross-linkers that are genetically fused to the proteins, simplifying synthesis by removing additional conjugation and purification steps. Non-covalently, self-associating, streptavidin homotetramer is a viable, biomolecular alternative to tetra-PEG. Here, a multi-arm streptavidin design is characterized as a protein-network material platform using various secondary, biomolecular cross-linkers, such as high-affinity physical (i.e., non-covalent), transient physical, spontaneous chemical (i.e., covalent), or stimuli-induced chemical cross-linkers. Stimuli-induced, chemical cross-linkers fused to multi-arm streptavidin nanohubs provide sufficient diffusion prior to initiating permanent covalent bonds, allowing proper characterization of streptavidin nanohubs. Surprisingly, non-covalently associated streptavidin nanohubs exhibit extreme stability, which translates into material properties that resemble hydrogels formed by chemical bonds even at high temperatures. Therefore, this study not only establishes that the streptavidin nanohub is an ideal multi-arm biopolymer precursor but also provides valuable guidance for designing self-assembling nanostructured molecular networks that can properly harness the extraordinary properties of protein-based building blocks.

Carboxylation reactions for integrating CO2 capture with the production of renewable monomers

AbstractResearch advances in carboxylation reactions using CO2 and light organic molecules of renewable origin are reviewed in this work, especially considering chemical catalytic approaches. Carboxylation, one of the most promising carbon capture and utilization (CCU) technologies, has a double environmental benefit, reducing greenhouse gas emissions by developing sustainable processes for commodity synthesis. The industrial interest is based on its potential use in the synthesis of biopolymer precursors from bioplatform molecules such as ethanol or furfural. Acrylic acid is obtained from ethylene (after ethanol dehydration), by a liquid phase reaction activated by organometallic catalysts. Promising yields are reported for different ligands and solvents, but a practical and sustainable implementation of these reactions is still challenging. On the other hand, the furoic acid carboxylation (furoic acid obtained by oxidation of furfural) is a solid‐gas reaction that produces 2,5furandicarboxylic acid in presence of alkaline carbonates. In this case, the economic feasibility is the main bottleneck to solve for scaling‐up, and efforts should be focused on substituting the most active alkaline carbonate (Cs) by more available alternatives. © 2022 The Authors. Greenhouse Gases: Science and Technology published by Society of Chemical Industry and John Wiley & Sons Ltd.

Spent coffee ground oil as a valuable source of epoxides and epoxidation derivatives: Quantitation and characterization using low-field NMR

Coffee waste, commonly referred to as spent coffee grounds (SCG), is currently discarded and has a negative impact on the environment. However, SCG are rich in valuable ingredients including 15–20% oil, which has a profile comparable to the vegetable oils used in the production of epoxides, biobased polyols, and polymers. Our first objective was to evaluate the efficiency of three different methods, namely Soxhlet, pressurized fluid extraction, and supercritical CO2 (scCO2) on SCG oil extraction. Additionally, we aimed to test the potential of low-field (LF) NMR to analyze SCG oil and monitor the formation of epoxides and biobased polyols. Finally, we evaluated epoxidized SCG oil as a plasticizer for improving the properties of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) bioplastic. Overall, SCG showed a promising potential as a source of biopolymer precursors, while LF NMR can be an efficient and economic tool for oil evaluation and reaction monitoring.

유액흐름 분석을 통한 바이오 폴리머 생산 효모의 교반조건 최적화

The medium used for microbial fermentation is generally in a liquid state, that is, a fluid. Here, there is no fixed shape, and the flow is irregular. Attempts have been made to analyze and predict the flow of the fluid. Kluyveromyces marxianus JMA-1 was developed to produce 3-hydroxy propionic acid (3-HP), a biopolymer precursor, and the agitation conditions were optimized by applying hydrodynamics. The maximum flow velocity and Γ1 value indicating the degree of rotation were the highest (45.35 ㎝/s and 0.72, respectively) in the control (Baffle 0) and the lowest (20.99 ㎝/s and 0.40, respectively) in Baffle 2. However, 3-HP production was the highest (8.82 ± 0.24 g/L) in Baffle 2 and the lowest (6.83 ± 0.11 g/L) in the control. The 3-HP production of Baffle 2 improved by 29% compared to that of the control.

Valorization of Spent Coffee Grounds as Precursors for Biopolymers and Composite Production.

Spent coffee grounds (SCG) are a current subject in many works since coffee is the second most consumed beverage worldwide; however, coffee generates a high amount of waste (SCG) and can cause environmental problems if not discarded properly. Therefore, several studies on SCG valorization have been published, highlighting its waste as a valuable resource for different applications, such as biofuel, energy, biopolymer precursors, and composite production. This review provides an overview of the works using SCG as biopolymer precursors and for polymer composite production. SCG are rich in carbohydrates, lipids, proteins, and minerals. In particular, carbohydrates (polysaccharides) can be extracted and fermented to synthesize lactic acid, succinic acid, or polyhydroxyalkanoate (PHA). On the other hand, it is possible to extract the coffee oil and to synthesize PHA from lipids. Moreover, SCG have been successfully used as a filler for composite production using different polymer matrices. The results show the reasonable mechanical, thermal, and rheological properties of SCG to support their applications, from food packaging to the automotive industry.

Efficient electrolysis of 5-hydroxymethylfurfural to the biopolymer-precursor furandicarboxylic acid in a zero-gap MEA-type electrolyzer

Replacement of today’s established chemical production processes by “green” sustainable alternatives has become a scientific priority. The oxidative conversion of 5-hydroxymethylfurfural (5-HMF) to the biopolymer component 2.5-furandicarboxylic acid paired with green electrolytic hydrogen production is a promising emerging green process. Here, we present a family of active selective and stable interlayer anion-tuned NiX (X = Fe, Mn, Co, V) bimetallic-layered, double-hydroxide catalysts for the selective oxidation of 5-HMF to 2.5-furandicarboxylic acid in a zero-gap MEA-type electrolyzer. We report that tuning the structural interlayer distance of the catalyst by anion exchange gives rise to previously unachieved catalytic performance for the anodic production of the biopolymer building block. Operando differential electrochemical mass spectrometry analysis reveals the electrode window for the perfectly selective HMF conversion. The role of the catalyst dopants, their real surface areas, the stability of the catalytic interface, and aspects of its favorable techno-economics are discussed. • Active, selective, and stable interlayer anion-tuned catalyst for biomass oxidation • Operating in a zero-gap MEA-type single electrolyzer cell • Operando analysis revealed the perfectly selective HMF conversion window Strasser et al. present a family of active selective and stable Ni-based catalysts for the selective oxidation of biomass in an electrolyzer. The biomass electrolysis device yields previously unachieved production of a biopolymer precursor and may offer techno-economic cost advantages.

Green Production of Biopolymer Precursors from Biomass-Derived Monosaccharides

Increasing demand of green chemical products calls upon the exploration of sustainable and renewable carbon resources beyond fossil-based materials. As such, biomass valorization has attracted increasing attention because biomass is the most widely available and sustainable carbon source. Among those biomass-derived platform chemicals, 5-hydroxymethylfurfural (HMF) has long been regarded as an attractive candidate for the production of numerous value-added products, including biopolymer precursors such as 2,5-furandicarboxylic acid (FDCA) and 2,5-bis(hydroxylmethyl)furan (BHMF). Nevertheless, the poor stability and difficult separation and purification of HMF makes it challenging to scale up the production of those valuable biopolymer precursors. Our group has initiated several projects focusing on the one-pot production of FDCA and BHMF from biomass-derived monosaccharides like fructose and glucose, bypassing the isolation of HMF as an intermediate product. We demonstrated that microwave-assisted transformation of these monosaccharides in biphasic solvent mixtures followed by electrocatalytic upgrading was able to produce both FDCA and BHMF with excellent yields and convenient separation, suggesting an economically attractive approach for large-scale production of biopolymer precursors from low-cost biomass-derived monosaccharides.

Development of catalysts for the hydrogenation of levulinic acid to gamma-valerolactone in the framework of the problem of cellulose conversion into valuable chemicals

Gamma-valerolactone (GVL) is a starting reagent for the production of fuels and fine chemicals. GVL can be used as a solvent, as part of an electrolyte, for the production of chemicals and fuel additives. It can be converted to liquid fuels such as valerian biofuels, liquid alkanes or valuable chemical intermediates such as 1,4-pentanediol or alkylpentenoates being biopolymer precursors. The production of GVL is based mainly on the hydrogenation of levulinic acid (LA), which can be obtained directly from cellulose by acid hydrolysis. This article describes the development of heterogeneous catalysts for the targeted conversion of LA to GVL. In order to analyze both achievements and unresolved problems in this area the emphasis was placed on the discussion of systems based on noble and non-noble metal catalysts, hydrogenation by means of hydrogen transfer.

Ni-Pd/γ-Al2O3 Catalysts in the Hydrogenation of Levulinic Acid and Hydroxymethylfurfural towards Value Added Chemicals

γ-Al2O3 supported Ni-Pd catalysts with different Ni:Pd ratios were studied in the hydrogenation of two industrially-relevant platform molecules derived from biomass, namely levulinic acid and hydroxymethylfurfural. The bimetallic catalysts showed better performances in both processes in comparison to the monometallic counterparts, for which a too strong interaction with the alumina support reduced the activity. The behavior of the bimetallic catalysts was dependent on the Ni:Pd ratio, and interestingly also on the targeted hydrogenation reaction. The Pd-modified Ni-rich system behaves like pure Ni catalyst, but with a strongly boosted activity due to a higher number of Ni active sites available, Pd being considered as a spectator. This high activity was manifested in the levulinic acid hydrogenation with formic acid used as an internal hydrogen source. This behavior differs from the case of the Pd-rich system modified by Ni, which displayed a much higher Pd dispersion on the support compared to the monometallic Pd catalyst. The higher availability of the Pd active sites while maintaining a high surface acidity allows the catalyst to push the HMF hydrodeoxygenation reaction forward towards the green biopolymer precursor 2,5-bis(hydroxymethyl)-tetrahydrofuran, and in consequence to strongly modify the selectivity of the reaction. In that case, residual chlorine was proposed to play a significant role, while Ni was considered as a spectator.

Solvothermal hydrodeoxygenation of hydroxymethylfurfural derived from biomass towards added value chemicals on Ni/TiO2 catalysts

Lignocellulosic biomass is one of the most abundant renewable source of commodity chemicals like hydroxymethylfurfural. Solvothermal hydrodeoxygenation of hydroxymethylfurfural towards value added chemicals was performed with a series of nickel based catalysts supported on different titania materials, ie. hydrothermally-prepared high aspect ratio and commercial TiO2 with different morphologies and crystallographic structures. The kind of titania strongly influenced the properties of the supported nickel nanoparticles, which allowed to tune the reaction selectivity towards specific products. Rutile-containing titania forced stronger Ni-Ti interaction, enhanced hydrogen adsorption, and formed larger Ni particles which resulted in high activity. Hydrothermally-prepared materials allowed to obtain selectively 2,5-bishydroxymethyltetrahydrofuran (biopolymer precursor) due a relatively small surface acidity and large Ni particles. By contrast, large surface area anatase with small nickel particles and small surface acidity allowed to selectively obtain 2,5-dimethylfuran (biofuel additive).

The production of valuable biopolymer precursors from fructose

A two-step process consisting of microwave dehydration and electrocatalysis is developed to synthesize biopolymer precursors from fructose without the separation of 5-hydroxymethylfurfural.

Facile Green Route to Ni/Co Oxide Nanoparticle Embedded 3D Graphitic Carbon Nanosheets for High Performance Hybrid Supercapacitor Devices

The demand for energy storage systems with superior performance has led to the creation of hybrid supercapacitor device. With proper designs, the hybrid supercapacitive materials can achieve high performance while reducing the overall cost. Herein, a novel method is developed for preparing three-dimensional hierarchical graphitic carbon nanocomposites with highly dispersed mixed Co–Ni oxide nanoparticles (Co–Ni–O/3DG) by a facile one-pot process involving carbonization and subsequent oxidation of metal ion doped biopolymer precursors. The mixed metal nanoparticles produced during carbonization enabled a top-down preparation of 3D graphitic carbon nanosheets. The nanocomposites were fully characterized and showed excellent electrochemical performance supported by the DFT calculation. Specific capacitance of 1586 F·g–1 was achieved (current density 1.0 A·g–1), with capacitance retention of 94.5% after 10 000 cycles demonstrating exceptional cycling stability. In an asymmetric full-cell system using a Co–Ni–...

Novel synthesis of coordination biopolymer precursor from oxidation of methyl cellulose by alkaline potassium permanganate

Novel synthesis of coordination biopolymer precursor from oxidation of methyl cellulose by alkaline potassium permanganate

Concept of rice husk biorefining for levulinic acid production integrating three steps: Multi-response optimization, new perceptions and limitations

Abstract Valuable intermediates for solvents, biofuels and biopolymer precursors are produced from levulinic acid (LA). In this study, rice husk (RH) was fractionated using a three-step biorefining approach for LA production: (1) acid pretreatment, (2) alkaline pretreatment and (3) catalytic depolymerization of cellulose. In third step, the H2SO4-acid concentration (Ad), reaction temperature (Td) and reaction time (td) on the LA concentration (CLA), selectivity (SLA) and yield percentage based on the theoretical value (Yt,LA), were investigated. Optimal values for CLA of 27.2 g/L, SLA of 62.2% and Yt,LA of 60.6 mol% were obtained at Ad of 5.0% w/v, Td of 175 °C and td of 75 min. A scenario based on 100 kg of dry RH produced 11.8 kg of LA with a yield of 42.9 mol% based on the theoretical values of the cellulose in the RH, as well as 12.5 kg of xylose, 12 kg of lignin and 2.9 kg of formic acid. Furthermore, the potential route to LA production with the requirement to remove the ash and with a low production of carbonaceous species (∼2.5 kg) was highlighted in this study. These results offer new insight into selective conversion of RH to bio-based products.

Salt melt synthesis of curved nitrogen-doped carbon nanostructures: ORR kinetics boost

Implementing metal-free electrocatalysts for the oxygen reduction reaction (ORR) and revealing crucial chemical or topographical parameters driving their activity are vital for the development of power cells. The carbon-based catalysts are very often synthesized through carbonization of biopolymers, in particular, those one containing nitrogen groups such as chitosan. Unfortunately, the resulting carbonaceous materials usually lack specific porosity and exhibit low catalytic activity.Here, we demonstrate that pyrolysis of chitosan in a ZnCl2 melt assisted by the presence of LiCl results not only in a highly porous activated carbon material with a specific surface area of 1317.97 m2/g and the total nitrogen content of 6.5%, but also induces unexpected curvature in the grown graphitic layers. This is the first work that shows curved graphene layers obtained from a biopolymer precursor by its pyrolytic decomposition in the melted salt media.On the other hand, a carbonaceous material obtained from chitosan but without the salts has very low specific surface area of 7.8 m2/g, possesses no specific structural features, and contains 4.7% of nitrogen.The electrochemical studies show, that the former material is highly active towards four-electron pathway of the ORR in terms of an onset potential (0.89 V vs RHE) and the turnover frequency (TOFmax = 0.095 e site−1 s−1).We attribute this high catalytic performance to the presence of the pyridinic and pyrrolic sites in the structure. The ORR kinetics is probably further promoted by curvature in the graphitic layers.

Light-activatable prodrugs based on hyaluronic acid biomaterials

Photosensitive in situ cross-linked hyaluronan (HA) hydrogels are prepared by modular chemoselective assembly from the biopolymer precursors and novel heterobifunctional linkers with middle photo-labile ortho-nitrobenzyl group and orthogonally reactive terminals. Starting from the thiol-modified HA and a linker with activated disulfide and hydrazide terminals, a photo-degradable HA hydrogel was prepared by the hydrazone cross-linking reaction. Moreover, a light-triggered drug-releasing hydrogel prodrug was constructed by an orthogonal conjugation of dopamine (DA) via a photo-labile linker to HA dually modified with thiol and hydrazide groups (hy-HA-SH) and a subsequent cross-linking with aldehyde-derivatized HA (HA-al). On-demand release of DA from the hydrogel was achieved upon exposure of the hydrogel to UV light whereas 11-fold less release of the drug was observed in the absence of light. The mechanical properties of the hydrogels, photodegradation kinetics, photorelease of the model drugs were studied by rheology, spectrophotometry, chromatography, and mass spectrometry. For the first time, integration of photolabile components into an actual polysaccharide of extracellular matrix was implemented for the light-controlled release of drug molecules.