Hydrodeoxygenation of Aqueous-Phase Catalytic Pyrolysis Oil to Liquid Hydrocarbons Using Multifunctional Nickel Catalyst

Production of low-sulfur fuels from catalytic pyrolysis of waste tires using formulated red mud catalyst

Waste tires (WT) are produced in millions of tons per annum and their safe disposal is always a major environmental challenge because of fire hazards and the increasing cost of landfills. WT has high organic matter content that can be converted into fuels and chemicals if suitable technologies can be developed. Herein we report the in situ catalytic pyrolysis of WT using formulated red mud catalyst to produce low sulfur fuel that can be fractionated or can be used without fractionation. The in situ catalytic pyrolysis was conducted at 450-550 °C using formulated red mud catalyst. The yield of pyrolysis liquids ranged from 35 to 40 wt%. The liquid was very rich in limonene and long chain aliphatic hydrocarbons. The catalyst was effective in removing the sulfur compounds in the oil through reactive adsorption desulfurization mechanism. The sulfur species reacted with hematite, calcite, sodium hydroxide, and zinc oxide to form sulfides and were retained in the catalyst. The minimum sulfur content of the catalytic pyrolysis oil was 0.38 wt%. After catalyst regeneration in air through combustion, the catalyst activity was restored, and the catalyst was reused.

In situ hydro-deoxygenation onto nickel-doped HZSM-5 zeolite catalyst for upgrading pyrolytic oil

Global energy demand has drastically increased due to urbanization and industrialization; thus, developing alternative renewable energy sources is urgently required. In the present work, upgrading the pyrolytic oil (PO) derived from fresh palm fruit was performed by the catalytic in situ hydrodeoxygenation (in situ HDO) process. Preparation of nickel-doped HZSM-5 zeolite (SiO2/Al2O3 = 40) was achieved by incipient wetness impregnation techniques using different weight percents of nickel dopant into HZSM-5. Nickel-doped HZSM-5 zeolite (Ni-HZSM-5) was further subjected to chemical reduction for 5 h in the oxygen-free environment (10% H2 and 90% N2) at 550 °C. The structural properties showed a potential reduction of NiO-HZSM-5 to Ni-HZSM-5, enhancing the catalytic potential. The morphological characterizations showed spherical-shaped Ni agglomerated onto HZSM-5. Acidity and oxygen contents in the pyrolytic oil were achieved by catalyst-aided HDO process at 220 °C for 6 h using methanol as a hydrogen donor. The catalytically upgraded pyrolytic oil (UPO) was analyzed for density, HHV, CHNO, and TGA. The best upgrading oil was distilled following ASTM D86 to separate gasoline, kerosene, and diesel. The acidity, density, HHV, and viscosity were measured before and after the upgradation processes. The results showed the potential impact of Ni with 10% doped on HZSM-5 on HDO reaction and illustrated the lowest oxygen content in upgraded pyrolytic oil products. Considerable decrease in viscosity and density level indicated that in situ HDO not only reduced oxygen content but also cracked pyrolytic oil to small molecules. The distilled product of upgrading oil was higher than pyrolytic oil by approximately 15% in volume. The viscosity, density, and HHV were under standard specifications of kerosene and diesel, except for acidity. However, the acidity was reduced by over 60% compared with raw material.

Emerging technologies for biofuel production: A critical review on recent progress, challenges and perspectives

Due to increasing anthropogenic activities, especially industry and transport, the fossil fuel demand and consumption have increased proportionally, causing serious environmental issues. This attracted researchers and scientists to develop new alternative energy sources. Therefore, this review covers the biofuel production potential and challenges related to various feedstocks and advances in process technologies. It has been concluded that the biofuels such as biodiesel, ethanol, bio-oil, syngas, Fischer-Tropsch H_2, and methane produced from crop plant residues, micro- and macroalgae and other biomass wastes using thermo-bio-chemical processes are an eco-friendly route for an energy source. Biofuels production and their uses in industries and transportation considerably minimize fossil fuel dependence. Literature analysis showed that biofuels generated from energy crops and microalgae could be the most efficient and attractive process. Recent progress in the field of biofuels using genetic engineering has larger perspectives in commercial-scale production. However, its large-scale production is still challenging; hence, to resolve this problem, it is essential to convert biomass in biofuels by developing novel technology to increase biofuel production to fulfil the current and future energy demand.

Upgrading of Oils from Biomass and Waste: Catalytic Hydrodeoxygenation

The continuous demand for fossil fuels has directed significant attention to developing new fuel sources to replace nonrenewable fossil fuels. Biomass and waste are suitable resources to produce proper alternative fuels instead of nonrenewable fuels. Upgrading bio-oil produced from biomass and waste pyrolysis is essential to be used as an alternative to nonrenewable fuel. The high oxygen content in the biomass and waste pyrolysis oil creates several undesirable properties in the oil, such as low energy density, instability that leads to polymerization, high viscosity, and corrosion on contact surfaces during storage and transportation. Therefore, various upgrading techniques have been developed for bio-oil upgrading, and several are introduced herein, with a focus on the hydrodeoxygenation (HDO) technique. Different oxygenated compounds were collected in this review, and the main issue caused by the high oxygen contents is discussed. Different groups of catalysts that have been applied in the literature for the HDO are presented. The HDO of various lignin-derived oxygenates and carbohydrate-derived oxygenates from the literature is summarized, and their mechanisms are presented. The catalyst’s deactivation and coke formation are discussed, and the techno-economic analysis of HDO is summarized. A promising technique for the HDO process using the microwave heating technique is proposed. A comparison between microwave heating versus conventional heating shows the benefits of applying the microwave heating technique. Finally, how the microwave can work to enhance the HDO process is presented.

Synergy between Ni and Co Nanoparticles Supported on Carbon in Guaiacol Conversion

Nickel-cobalt bimetallic catalysts supported on high surface area graphite with different Ni:Co ratios (3:1, 2:1 and 1:1) and the monometallic Ni and Co were prepared by wetness impregnation method. The catalysts were tested in hydrodeoxygenation (HDO) of guaiacol in the liquid phase at 50 bar of H2 and 300 °C. The materials were characterized by N2 adsorption-desorption, XRD, TEM/STEM, H2-TPR, and CO-chemisorption to assess their properties and correlate them with the catalytic results. The activity was higher on the bimetallic catalysts and followed the trend NiCo2:1/G ∼ NiCo3:1/G > NiCo1:1/G > Co/G > Ni/G. Also, selectivity results showed that Ni was more active in the hydrogenation favoring cyclohexanol production from phenol, while this was inhibited on the Co-containing catalysts. Hence, the results showed that synergy was created between Ni and Co and that their interaction, properties, and catalytic performance depend on the metals' ratio.

Effect of H-ZSM-5 and Al-MCM-41 Proportions in Catalyst Mixtures on the Composition of Bio-Oil in Ex-Situ Catalytic Pyrolysis of Lignocellulose Biomass

The present work is an attempt to optimize the proportion of H-ZSM-5 and Al-MCM-41 in the catalyst mixtures for lignocellulose biomass catalytic pyrolysis. The H-ZSM-5 proportions of 50.0, 66.7, 75.0, and 87.5 wt.% were examined for the upgrading of biomass pyrolysis vapors in the fixed bed reactor. The catalyst mixture of 87.5 wt.% H-ZSM-5 and 12.5 wt.% Al-MCM-41 was found most effective in this study, giving a 65.75% deoxygenation degree. An organic-rich bio-oil was obtained with 74.90 wt.% of carbon content, 8 wt.% of hydrogen content, 15 wt.% oxygen content, a 0.39 wt.% water content, and a high heating value of 34.15 MJ/kg. The highest amount of desirable compounds among the studied catalytic experiments, which include hydrocarbons, phenols, furans, and alcohols, was obtained with a value of 95.89%. A significant improvement in the quality of bio-oil with the utilization of H-ZSM-5 and Al-MCM-41 catalyst mixtures was the rise of desirable compounds in bio-oil.

Enhancement of biogas production from wastewater sludge via anaerobic digestion assisted with biochar amendment

Studies have shown that biochar enhances methane formation due to the presence of redox active moieties and its conductive properties. This study investigated the influence of biochar, which was produced from Douglas fir pyrolysis, on biogas production and microbial community during anaerobic digestion (AD) of wastewater sludge. The results showed that biochar significantly enhances methane (CH₄) production rate and increases its final yield during AD. The cumulative highest CH₄ production obtaining in cultures with DF500 (biochar from Douglas fir at 500 °C) were about 11% and 98% more than the culture without biochar at 37 °C and 25 °C AD temperature, respectively. At 55 °C, the maximum CH₄ yield reached 172.3 ml/g COD with DF730, which was about 48.3% more than control culture. The microbial community analysis results showed that biochar could up-regulate the role of micro-ecology especially the methanogens and improve the AD process.

Hydrogen production via thermocatalytic decomposition of methane using carbon-based catalysts

Thermocatalytic decomposition (TCD) of methane is one of the most effective methods for pure hydrogen production. Catalysts were selected for TCD of methane in this study to utilize biochar as a catalyst. Among these catalysts, two catalysts (named activated biochar (AB) and heat-treated biochar (HB)) were prepared from Douglas fir, whereas the other four were prepared using commercial activated carbon and zeolite with and without doping ruthenium metal. The catalysts were characterized using XRD, SEM imaging, TEM, H₂-TPR, and BET specific surface area and pore size analysis. The Ru doped commercial activated carbon catalyst (Ru–AC) was deactivated continuously during a 60 h reaction run, whereas AB exhibited comparatively stable methane conversion up to 60 h. The methane conversion was 21% for Ru–AC and 51% for AB after 60 h of reaction time at 800 °C. The very high surface area of AB (∼3250 m² g⁻¹) and its microporosity compared to other catalysts could have resulted in resistance against rapid deactivation. Furthermore, carbon nanotube by-products were observed in TEM images of solid residues that could form due to the presence of alkali metals in the biochar. Carbon nanotube formation could contribute significantly to the extended life of AB.

Methane decomposition over a carbon supported Ru catalyst (Ru–AC) and activated biochar (AB) for hydrogen production.

Role of Support in Hydrocracking of n-hexadecane over Sulfided NiMo Catalysts

The graphene nanosheets (GNS) have been considered as a support for the synthesis of catalysts applied in various catalytic reactions. In this research, the hydrocracking (HCK) of n-hexadecane as a model component of the long chain paraffin was carried out using synthesized Ni-Mo/GNS and commercial Ni-Mo/Al2O3-SiO2 catalysts in a fixed-bed reactor. The physico-chemical properties of catalysts were determined using XRF, TEM, XRD, TGA and NH3-TPD analysis. The effect of support on the conversion and product distribution in HCK of n-hexadecane was investigated. The stability of the catalysts in the presence of water and coke deposition was examined for the HCK of nonconventional feeds. The obtained results revealed that the active metals were anchored on the functionalized GNS and the stability of Ni-Mo/GNS was significantly increased compared to commercial catalyst. The obtained results indicated that the GNS-supported catalysts have a higher potential for HCK of n-hexadecane in comparison to commercial Ni-Mo/ Al2O3-SiO2 catalysts.

Waste Seashells as a Highly Active Catalyst for Cyclopentanone Self-Aldol Condensation

For the first time, waste-seashell-derived CaO catalysts were used as high-performance solid base catalysts for cyclopentanone self-condensation, which is an important reaction in bio-jet fuel or perfume precursor synthesis. Among the investigated seashell-derived catalysts, Scapharca Broughtonii-derived CaO catalyst (S-shell-750) exhibited the highest dimer yield (92.1%), which was comparable with commercial CaO (88.2%). The activity sequence of different catalysts was consistent with the CaO purity sequence and contact angle sequence. X-ray diffraction (XRD) results showed that CaCO3 in waste shell were completely converted to CaO after calcination at 750 °C or above for 4 h. CO2 temperature-programmed desorption (CO2-TPD) results indicate that both the amount and strength of base sites increase significantly when the calcination temperature climbs to 750 °C. Therefore, we can attribute the excellent performance of S-shell-750/850/950 catalysts to the higher CaO content, relatively low hydrophilicity, and stronger acidity and basicity of this catalyst. This study developed a new route for waste shell utilization in bio-derived ketone aldol condensation.

Effect of Metal Loading in Unpromoted and Promoted CoMo/Al2O3–TiO2 Catalysts for the Hydrodeoxygenation of Phenol

This paper reports the effects of changes in the supported active phase concentration over titania containing mixed oxides catalysts for hydrodeoxygenation (HDO). Mo and CoMo supported on sol–gel Al2O3–TiO2 (Al/Ti = 2) were synthetized and tested for the HDO of phenol in a batch reactor at 5.5 MPa, 593 K, and 100 ppm S. Characterization results showed that the increase in Mo loading led to an increase in the amount of oxide Mo species with octahedral coordination (MoOh), which produced more active sites and augmented the catalytic activity. The study of the change of Co concentration allowed prototypes of the oxide species and their relationship with the CoMo/AT2 activity to be described. Catalysts were tested at four different Co/(Co + Mo) ratios. The results presented a correlation between the available fraction of CoOh and the catalytic performance. At low CoOh fractions (Co/(Co + Mo) = 0.1), Co could not promote all MoS2 slabs and metallic sites from this latter phase performed the reaction. Also, at high Co/(Co + Mo) ratios (0.3 and 0.4), there was a loss of Co species. The Co/(Co + Mo) = 0.2 ratio presented an optimum amount of available CoOh and catalytic activity since the XPS results indicated a higher concentration of the CoMoS phase than at a higher ratio.

Evaluating the Effects of KCl on Thermal Behavior and Reaction Kinetics of Medium Density Fiberboard Pyrolysis

The effects of potassium chloride (KCl) on the pyrolysis of medium density fiberboard (MDF) were investigated by using thermogravimetry/Fourier-transfer infrared spectroscopy (TG-FTIR). Five MDF samples treated with different KCl concentrations (0%, 0.5%, 1%, 2% and 3%) were heated with a heating rate of 20 °C/min. The thermogravimetry (TG) results showed that KCl caused the primary pyrolysis stage towards lower temperatures. The FTIR results indicated that with the concentrations of KCl, the formation of CH₄ and C=O functional groups decreased while the formation of CO₂ and CO increased. To figure out the reason for the observed phenomena, the kinetic parameters in primary pyrolysis and the secondary charring reaction were estimated by a differential evolution (DE) optimization algorithm. The prediction indicated that KCl shifted the initial degradation temperature of each component of MDF towards a lower temperature. Char and gas yields increased with the concentration of KCl, whereas the tar yield reduced. The changes in activation energies revealed that KCl played a catalyst role in the reaction of resin, hemicellulose and cellulose in primary pyrolysis. For lignin, KCl had little effect. In the secondary charring reaction, KCl apparently promoted the reaction of tar. The catalytic effect of KCl on MDF pyrolysis was the combination of primary pyrolysis and the secondary charring reaction. Finally, the optimal catalytic concentration for KCl on MDF pyrolysis was analyzed.

Study on the Product Characteristics of Pyrolysis Lignin with Calcium Salt Additives

This study investigated and compared the product characteristics of pyrolysis lignin under different catalytic effects resulting from various calcium salts. The pyrolysis of lignin was conducted in a fixed-bed reactor with calcium salt additives, which included CaCl₂, Ca(OH)₂, and Ca(HCOO)₂. The compositions of gas and bio-oil were detected using gas chromatography/mass spectrometry (GC/MS). The characterizations of chars were examined using Brunauer–Emmett–Teller (BET) surface area and scanning electron microscopy (SEM). The results indicate that all three types of calcium salts helped to promote bio-oil yield and inhibit gas and char from forming. Regarding the composition of gas products, calcium salt additives increased the concentrations of H₂ and CH₄ while decreasing the concentration of CO. In addition, calcium salt additives facilitated the formation of phenol and alkyl-phenols in bio-oil, but reduced the yields of guaiacol and vanillin, in the order CaCl₂ < Ca(OH)₂ < Ca(HCOO)₂. Furthermore, when compared with the addition of CaCl₂, the chars prepared by the addition of Ca(OH)₂ and Ca(HCOO)₂ had relatively higher BET surface areas. In conclusion, Ca(HCOO)₂ had the greatest positive influence in regard to the product quality of lignin pyrolysis whilst also elevating the yield of value-added chemicals in bio-oils.

Thermal and Catalytic Pyrolysis of Dodecanoic Acid on SAPO-5 and Al-MCM-41 Catalysts

In this study, dodecanoic acid was decomposed during fast pyrolysis experiments either thermally or in the presence of SAPO-5 and Al-MCM-41catalysts. The catalysts were synthesized by a hydrothermal route and subsequently characterized by XRD, TPD-NH3, and TGA, and dodecanoic acid was characterized by TGA and DSC. Analysis of the post-pyrolysis products was performed online by gas chromatography coupled with mass spectrometry (GC-MS). The results from pyrolysis at 650 °C indicated that the nature of the catalysts strongly influences the composition of the products. Linear alkenes were standard products for all pyrolysis experiments, but with Al-MCM-41, various alkene isomers with a linear and cyclic structure formed, as well as saturated and aromatic hydrocarbons. As a whole, Al-MCM-41 led to a much higher dodecanoic acid conversion and higher deoxygenation than SAPO-5. As these catalysts present small differences in strong acid site density, the difference in the global conversion of dodecanoic acid could be attributed to textural characteristics such as pore volume and surface area. In this case, the textural properties of the SAPO-5 are much lower when compared to Al-MCM-41 and, due to a lower accessibility of the reactant molecule to the acidic sites of SAPO-5, partially blocked for fatty acid molecules by the considerable amount of amorphous material, as detected by XRD.

Aqueous Dehydration, Hydrogenation and Hydrodeoxygenation Reactions of Bio-Based Mucic Acid over Ni, NiMo, Pt, Rh, and Ru on Neutral or Acidic Catalyst Supports

Hydrotreatment of mucic acid (also known as galactaric acid, an glucaric acid enantiomer), one of the most promising bio-based platform chemicals, was systematically investigated in aqueous media over alumina, silica, or carbon-supported transition (nickel and nickel-molybdenum) or noble (platinum, ruthenium and rhodium) metals. Mucic acid was only converted into mucic-1,4-lactone under non-catalytic reaction conditions in N2 atmosphere, while the 5 MPa gaseous H2 addition triggers hydrogenation in the bulk phase, resulting in formation of galacturonic and galactonic acid. However, dehydroxylation, hydrogenation, decarbonylation, decarboxylation, and cyclization occurred during catalytic hydrotreatment, forming various partially and completely deoxygenated products with a chain length of 3–6 C atoms. Characterization results of tested catalysts were correlated with their activity and selectivity. Insufficient pore diameter of microporous supports completely hindered the mass transfer of reactants to the active sites, resulting in negligible conversion of mucic acid. A comprehensive reaction pathway network was proposed and several industrially interesting compounds were formed, including levulinic acid, furoic acid, and adipic acid. However, selectivity towards adipic acid, a bio-based nylon 6,6 precursor, was low (up to 5 mol%) in aqueous media and elevated temperatures.

Hydrocracking of Athabasca Vacuum Residue Using Ni-Mo-Supported Drill Cuttings

Ni-Mo supported drill cuttings were used to catalyze the hydrocracking (HDC) of Athabasca vacuum residue (AVR) in an autoclave. Drill cuttings are a common waste product that are, depending on their origin, plentiful in acidic sites. The catalyst was prepared using the wet impregnation method. HDC was carried out at both low and high H2 pressure at 400 °C. Control thermal cracking (TC) and HDC runs with and without raw drill cuttings were performed to better examine the role of the supported drill cuttings catalyst. The quality in terms of viscosity and °API gravity, and the yield of various fractions making up the product oil were used to gauge the performance of the catalyst. Similar temperature and energy profiles between TC and HDC suggested strong overlap between the two different reactions, despite H2 presence. Nevertheless, supported drill cuttings runs at high H2 pressures promoted H2 consumption to a strong extent. Consequently, the liquid yield was the highest (~75 wt.%) and the coke yield was negligible. High temperature simulated distillation results revealed a residue conversion of ~55% for both low and high pressure HDC catalytic runs. The product oil quality with respect to viscosity and °API gravity was also found to be comparable between the low and high pressure HDC catalytic runs. Accordingly, no trade-off between liquid yield and quality was incurred at high H2 pressure. Effectively the supported drill cuttings drastically reduced coke formation, while maximizing the yield of the desired liquid product.

ZnO/Ionic Liquid Catalyzed Biodiesel Production from Renewable and Waste Lipids as Feedstocks

A new protocol for biodiesel production is proposed, based on a binary ZnO/TBAI (TBAI = tetrabutylammonium iodide) catalytic system. Zinc oxide acts as a heterogeneous, bifunctional Lewis acid/base catalyst, while TBAI plays the role of phase transfer agent. Being composed by the bulk form powders, the whole catalyst system proved to be easy to use, without requiring nano-structuration or tedious and costly preparation or pre-activation procedures. In addition, due to the amphoteric properties of ZnO, the catalyst can simultaneously promote transesterification and esterification processes, thus becoming applicable to common vegetable oils (e.g., soybean, jatropha, linseed, etc.) and animal fats (lard and fish oil), but also to waste lipids such as cooking oils (WCOs), highly acidic lipids from oil industry processing, and lipid fractions of municipal sewage sludge. Reusability of the catalyst system together with kinetic (Ea) and thermodynamic parameters of activation (ΔG‡ and ΔH‡) are also studied for transesterification reaction.

Mechanochemical Preparation of Novel Polysaccharide-Supported Nb2O5 Catalysts

Polysaccharides extracted from natural sources can be used as starting material for the preparation of nanoparticle supported composites. A novel family of bio-nanocomposites was mechanochemically synthesized by using niobium oxide and enzymatically produced polysaccharides. The structural, textural and surface properties of nanomaterials, were determined by X-Ray diffraction (XRD), nitrogen adsorption-desorption (N₂ porosimetry), pulse chromatography, infrared spectroscopy (ATR-IR) and dynamic light scattering (DLS). Selective oxidation of isoeugenol to vanillin was carried out to demonstrate the catalytic activity of the Nb-polysaccharides nanocomposites. Interestingly, most of our material showed high conversion of isoeugenol (60–70%) with selectivity to vanillin over 40%. The optimum conversion and selectivity were achieved with a reaction time between 8 and 24 h.

Catalytic Pyrolysis of Biomass and Polymer Wastes

Oil produced by the pyrolysis of biomass and co-pyrolysis of biomass with waste synthetic polymers has significant potential as a substitute for fossil fuels. However, the relatively poor properties found in pyrolysis oil—such as high oxygen content, low caloric value, and physicochemical instability—hampers its practical utilization as a commercial petroleum fuel replacement or additive. This review focuses on pyrolysis catalyst design, impact of using real waste feedstocks, catalyst deactivation and regeneration, and optimization of product distributions to support the production of high value-added products. Co-pyrolysis of two or more feedstock materials is shown to increase oil yield, caloric value, and aromatic hydrocarbon content. In addition, the co-pyrolysis of biomass and polymer waste can contribute to a reduction in production costs, expand waste disposal options, and reduce environmental impacts. Several promising options for catalytic pyrolysis to become industrially viable are also discussed.

Catalytic Co-Pyrolysis of Kraft Lignin with Refuse-Derived Fuels Using Ni-Loaded ZSM-5 Type Catalysts

The catalytic co-pyrolysis (CCP) of Kraft lignin (KL) with refuse-derived fuels (RDF) over HZSM-5, Ni/HZSM-5, and NiDHZSM-5 (Ni/desilicated HZSM-5) was carried out using pyrolyzer-gas chromatography/mass spectrometry (Py-GC/MS) to determine the effects of the nickel loading, desilication of HZSM-5, and co-pyrolysis of KL with RDF. The catalysts were characterized by Brunauer–Emmett–Teller surface area, X-ray diffraction, and NH3-temperature programed desorption. The nickel-impregnated catalyst improved the catalytic upgrading efficiency and increased the aromatic hydrocarbon production. Compared to KL, the catalytic pyrolysis of RDF produced larger amounts of aromatic hydrocarbons due to the higher H/Ceff ratio. The CCP of KL with RDF enhanced the production of aromatic hydrocarbons by the synergistic effect of hydrogen rich feedstock co-feeding. In particular, Ni/DHZSM-5 showed higher aromatic hydrocarbon formation owing to its higher acidity and mesoporosity.

Characterization of a New Glyoxal Oxidase from the Thermophilic Fungus Myceliophthora thermophila M77: Hydrogen Peroxide Production Retained in 5-Hydroxymethylfurfural Oxidation

Myceliophthora thermophyla is a thermophilic industrially relevant fungus that secretes an assortment of hydrolytic and oxidative enzymes for lignocellulose degradation. Among them is glyoxal oxidase (MtGLOx), an extracellular oxidoreductase that oxidizes several aldehydes and α-hydroxy carbonyl substrates coupled to the reduction of O2 to H2O2. This copper metalloprotein belongs to a class of enzymes called radical copper oxidases (CRO) and to the “auxiliary activities” subfamily AA5_1 that is based on the Carbohydrate-Active enZYmes (CAZy) database. Only a few members of this family have been characterized to date. Here, we report the recombinant production, characterization, and structure-function analysis of MtGLOx. Electron Paramagnetic Resonance (EPR) spectroscopy confirmed MtGLOx to be a radical-coupled copper complex and small angle X-ray scattering (SAXS) revealed an extended spatial arrangement of the catalytic and four N-terminal WSC domains. Furthermore, we demonstrate that methylglyoxal and 5-hydroxymethylfurfural (HMF), a fermentation inhibitor, are substrates for the enzyme.