Primary Reaction Pathway Research Articles

Kinetic barriers, rate constants and branching ratios for unimolecular reactions of methyl octanoate peroxy radicals: A computational study of a mid-sized biodiesel fuel surrogate

Towards the goal of establishing kinetic database for low-temperature combustion (T < 1000K) of mid-sized biodiesel surrogates, the study uses quantum chemistry and statistical kinetic methods to investigate three primary unimolecular reaction pathways of methyl octanoate peroxy radicals, including dissociation, isomerization and concerted elimination. We calculate kinetic barriers and pressure-dependent rate constants at 500–1000K. The comparison between our computed and previously estimated rate constants offers further insight into how transition state structures and molecular mechanics are correlated with reaction kinetics. In the branching ratio analysis, we investigate the proposed unimolecular reactions and factors affecting these kinetic characteristics. For the first time, the previously measured oxidation rates of methyl octanoate under the cool flame regime (560–1000K) are computationally verified by kinetic modeling that reflects the contribution of the present submodel to an existing detailed mechanism of methyl octanoate. Consequently, the rate-of-production analysis reveals the significance of newly proposed reaction pathways.

Kinetic and spectroscopic evidence for reaction pathways and intermediates for olefin epoxidation on Nb in *BEA

The selective epoxidation of olefins with hydrogen peroxide (H2O2) over transition metal substituted zeolites is less environmentally impactful than epoxidation schemes that use chlorinated or organic oxidants. The structure and reactivity of reactive intermediates derived from H2O2 and the mechanism for olefin epoxidation on such materials are debated. Here, cyclohexene oxide formation and H2O2 decomposition rates (measured as functions of reactant and product concentrations) and in situ infrared (IR) and UV-vis spectroscopy are used to probe the intervening elementary steps for cyclohexene (C6H10) epoxidation and the identity of the reactive intermediates on a Nb-β catalyst. IR and UV-vis spectra acquired in situ show that the reactive intermediates are predominantly superoxide species (NbIV-(O2)−, observed also by X-ray photoelectron spectroscopy), which form by the irreversible activation of H2O2 over Nb centers. Similar M-(O2)∗ (M=Ti or Ta) intermediates were previously assumed to form via reversible processes; however, in situ IR and UV-vis measurements directly show that NbIV-(O2)− forms irreversibly in both H2O and acetonitrile. Activation enthalpies (ΔH‡) for C6H10 epoxidation are 27kJmol−1 higher than for H2O2 decomposition, while activation entropies (ΔS‡) for epoxidation are 56Jmol−1K−1 lower than for H2O2. These comparisons show that the selectivities for epoxidation, via primary reaction pathways, increase with increasing reaction temperatures. Collectively, these results provide a self-consistent mechanism for C6H10 epoxidation that is also in agreement with previously published data. These findings will aid the rational design and study of alternative metal oxide catalysts for olefin oxidation reactions.

Contribution of persulfate in UV-254 nm activated systems for complete degradation of chloramphenicol antibiotic in water

In this work, we investigated the treatment of chloramphenicol (CAP) solution using a persulfate (PS)-based Advanced Oxidation Process (AOP) generating sulfate and hydroxyl radicals upon exposure to low intensity UV. Experiments were carried out at 20°C in photo-reactors equipped with 4.9 Watt Low Pressure Mercury Lamp (LPHgL). Several experimental parameters were varied and evaluated to optimize the degradation process reaching therefore better mineralization of CAP and its degradation products. Parameters included: UV power, PS concentration, pH, dissolved ions e.g. HCO3−, Cl−, SO42−, nutrients e.g. NO3−, NO2−, HPO42− and organic acids e.g. fumaric acid, humic acids. Results showed that: (i) CAP degradation followed pseudo-first order kinetics with an optimized t1/2 lesser than 5min under controlled conditions; (ii) CAP mineralization extent was proportional to the amount of PS used (0.25–5.0mM) with no mineralization noticed in the absence of PS; (iii) The calculated % reaction stoichiometric efficiency (RSE) reached values up to 52% comparable to that of RSE obtained in thermally activated PS systems, however, exceeding by far RSE values in chemically activated systems; (iv) PS can be sustained in solution at high % RSE upon sequential CAP addition; (v) CAP partially disappeared along with coliforms in CAP-spiked non-treated wastewater samples using UV/PS system under moderate conditions; (vi) The optimized AOP showed an experimental break-even point between mineralization and CAP degradation at [PS]=0.5mM and a fluence of 330J for 1h reaction. CAP transformation products were identified by HPLC/MS and a CAP primary degradation reaction pathway was proposed. This study demonstrated that UV/PS system is much stronger than UV-only system for rapid and complete mineralization of CAP in water.

A detailed product analysis of bio-oil from fast pyrolysis of demineralised and torrefied biomass

Acid leaching and torrefaction were investigated as biomass pretreatments for fast pyrolysis of Pinus radiata. Both pretreatments were required to limit competitive primary and secondary reactions of pyrolysis vapours catalysed by water, organic acids, and inorganics present in the biomass. Torrefaction reduces the cost of acid leaching by providing the leaching reagent and eliminating the need for biomass rinsing prior to the leaching. It also reduces the biomass grinding costs, which helps offset the additional process costs of pretreating biomass. Acid leaching was required because pyrolysis of solely torrefied biomass was constrained by the high torrefaction temperatures required for significant bio-oil improvements, leading to low bio-oil yields due to the mass loss during torrefaction and increased char formation during pyrolysis. Finally, the reduced thermal conductivity of dry torrefied biomass increased the time avaliable for inorganics to catalyse primary reaction pathways during the biomass heating. The optimal pretreatment conditions were 1% acetic acid leaching at 30°C for 4h followed by torrefaction at 270°C for 20min. Pyrolysis of raw biomass yielded (dry basis) 55.3wt% bio-oil, 25.0wt%, char, and 12.5wt% non-condensable gas, whereas pyrolysis of pretreated biomass yielded 57.8wt% bio-oil, 23.7wt%, char, and 11.5wt% non-condensable gas. Integrating leaching and torrefaction as biomass pretreatments significantly reduced the heterogeneous and homogeneous secondary reactions of pyrolysis vapours. This integrated pretreatment improved the bio-oil’s quality in terms of the organic acid (2.46–0.16%), water (16.8–3.6wt%), aldehyde (1.58–0.50%), high molecular weight compound (10.2–4.2%), and inorganic (0.162–0.091wt%) content, as well as the stability.

The Photochemical Branching Ratio in 1,6-Dinitropyrene Depends on the Excitation Energy.

Nitropolycyclic aromatic hydrocarbons constitute one of the most disconcerting classes of pollutants. Photochemical degradation is thought to be a primary mode of their natural removal from the environment, but the microscopic mechanism leading to product formation as a function of excitation wavelength is poorly understood. In this Letter, it is revealed that excitation of 1,6-dinitropyrene with 425, 415, or 340 nm radiation leads to an increasing amount of radical production through photodissociation at the expense of triplet-state population-the two primary reaction pathways in this class of pollutants. Radical formation requires overcoming an energy barrier in the excited singlet manifold. This activation energy explains the large fraction of the initial singlet-state population that intersystem crosses to a doorway triplet state, instead of leading overwhelmingly to photodissociation. The unforeseen excitation wavelength dependence of this branching process is expected to regulate the photochemistry of 1,6-dinitropyrene and possibly of other nitroaromatic pollutants in the environment.

1,2-Shift of Element-Centered Groups (RnE) in Carbenoid Anions [RnECF2CFCl]−and its Relevance for Nucleophilic Vinylic Substitution: a DFT Study

The 1,2-shift of β-substituent to the carbenic or carbenoid centre is one of the primary reaction pathways for these intermediates. In the present work the 1,2-shift of various element-centered groups in carbenoid anions [RnECF2CFCl]– (E=C, N, Si, Ge, Sn, P, As, Sb, S, Se, Te, R=Me) is for the first time examined with the help of density functional theory calculations. The calculations were performed on the models of free carbenoid anions [RnECF2CFCl]– and their Na+ and [NMe4]+ salts. In all cases the 1,2-shift of the RnE-groups formed by the elements of the third and subsequent periods was calculated to be much more facile than for carbon-centred groups. Calculated ΔG≠ are as low as 4–6 kcal/mol for the 5−th period Me3Sn- and Me2Sb groups. An even more facile 1,2-shift precludes the existence of the corresponding β-element substituted carbenes. Periodicity trends, correlation analysis and NBO analysis of the transition state structures were used to discriminate between different intrinsic mechanisms. In free carbenoid anions the main mechanisms of 1,2-shift of RnE-groups are: a) electrophilic shift of R3E- (E= Si, Ge, Sn) and Ph-groups; b) nucleophilic shift of RS- group c) dyotropic-type pathway for RS-, RSe-, RO-, R2N and R3C- groups. In carbenoid ion pairs: a) nucleophilic shift of RnE- (E=Si, Ge, Sn P, As, Sb) and Re(CO)5- groups; b) nucleophilic substitution involving the lone pair of RS-, RSe- and R2N- groups.

Ozonation of pyridine and other N-heterocyclic aromatic compounds: Kinetics, stoichiometry, identification of products and elucidation of pathways

Pyridine, pyridazine, pyrimidine and pyrazine were investigated in their reaction with ozone. These compounds are archetypes for heterocyclic aromatic amines, a structural unit that is often present in pharmaceuticals, pesticides and dyestuffs (e.g., enoxacin, pyrazineamide or pyrimethamine). The investigated target compounds react with ozone with rate constants ranging from 0.37 to 57 M−1 s−1, hampering their degradation during ozonation. In OH radical scavenged systems the reaction of ozone with pyridine and pyridazine is characterized by high transformation (per ozone consumed) of 55 and 54%, respectively. In non scavenged system the transformation drops to 52 and 12%, respectively. However, in the reaction of pyrimidine and pyrazine with ozone this is reversed. Here, in an OH radical scavenged system the compound transformation is much lower (2.1 and 14%, respectively) than in non scavenged one (22 and 25%, respectively). This is confirmed by corresponding high N-oxide formation in the ozonation of pyridine and pyridazine, but probably low formation in the reaction of pyrimidine and pyrazine with ozone. With respect to reaction mechanisms, it is suggested that ozone adduct formation at nitrogen is the primary step in the ozonation of pyridine and pyridazine. On the contrary, ozone adduct formation to the aromatic ring seems to occur especially in the ozonation of pyrimidine as inferred from hydrogen peroxide yield. However, also OH radical reactions are supposed processes in the case of pyrimidine and in particular for pyrazine, albeit negligible OH radical yields are obtained. The low compound transformation in OH radical scavenged system can prove this. As a result of negligible OH radical yields in all cases (less than 6%) electron transfer as primary reaction pathway plays a subordinate role.

Product Channels in the Reaction of the Hydroxymethyl Radical with Nitric Oxide.

The products of the reaction of CH2OH with NO were studied by infrared diode laser spectroscopy. Products were detected to determine the branching ratios of the CH2OH + NO reaction. HNCO was detected in 10.3 ± 2% yields. No other products were detected in significant quantities, indicating that adduct formation is the primary reaction pathway. Ab initio calculations of the potential energy surface show a low energy pathway to HNCO + H2O, but no other bimolecular channels, in agreement with the experiments.

Alkaline‐Earth‐Metal‐Catalyzed Thin‐Film Pyrolysis of Cellulose

AbstractThe conversion of lignocellulosic biomass to “bio‐oils” by thermochemical pyrolysis is a promising reactor technology for renewable chemicals and biofuels. Although the fundamental understanding of relevant catalysts within reacting biomass particles is only in its infancy, it is known that inorganic materials naturally present within biomass act as catalysts that limit the yield of bio‐oil and alter the product distribution. In this work, the effect of alkaline earth metals on cellulose pyrolysis chemistry was investigated to determine the catalytic effect on primary (transport‐free) and secondary (diffusion‐limited) reaction pathways. The catalytic materials included homogeneous metal ions Ca2+ and Mg2+ from their inorganic salts, Ca(NO3)2 and Mg(NO3)2, and their corresponding heterogeneous metal oxides, CaO and MgO. Although the oxides had a limited impact on cellulose pyrolysis chemistry, the metal ions altered the secondary reaction pathways of cellulose significantly under diffusion‐limited conditions common to lignocellulosic particles within industrial reactors.

Ab initio derived reaction mechanism for the dry reforming of methane on Rh doped pyrochlore catalysts

The conversion of methane into syngas is of growing importance given recent increases in methane production worldwide. Furthermore, using CO2 as the co-feed offers many environmental advantages. To this end, experimentalists have shown that Rh-substituted lanthanum zirconate pyrochlore (LRhZ) catalysts are active and stable at the high temperatures needed for the dry reforming of methane (DRM). To enable further improvements to these catalysts, the reaction mechanism for DRM on LRhZ catalysts was attained using density functional theory (DFT). Following the identification of favored reaction sites for all elementary reactions, reaction and activation energies were calculated and used to discern the primary reaction pathway. Simulations show that inclusion of Rh decreases activation barriers, including the barriers for the two rate limiting steps (CH2 oxygenation and CHO dehydrogenation), which makes the plane (111) catalytically active for DRM. The slow steps are on the CH4 dehydrogenation/oxygenation path, which agrees with experimental observations.

Rapid Removal of Tetrabromobisphenol A by Ozonation in Water: Oxidation Products, Reaction Pathways and Toxicity Assessment.

Tetrabromobisphenol A (TBBPA) is one of the most widely used brominated flame retardants and has attracted more and more attention. In this work, the parent TBBPA with an initial concentration of 100 mg/L was completely removed after 6 min of ozonation at pH 8.0, and alkaline conditions favored a more rapid removal than acidic and neutral conditions. The presence of typical anions and humic acid did not significantly affect the degradation of TBBPA. The quenching test using isopropanol indicated that direct ozone oxidation played a dominant role during this process. Seventeen reaction intermediates and products were identified using an electrospray time-of-flight mass spectrometer. Notably, the generation of 2,4,6-tribromophenol was first observed in the degradation process of TBBPA. The evolution of reaction products showed that ozonation is an efficient treatment for removal of both TBBPA and intermediates. Sequential transformation of organic bromine to bromide and bromate was confirmed by ion chromatography analysis. Two primary reaction pathways that involve cleavage of central carbon atom and benzene ring cleavage concomitant with debromination were thus proposed and further justified by calculations of frontier electron densities. Furthermore, the total organic carbon data suggested a low mineralization rate, even after the complete removal of TBBPA. Meanwhile, the acute aqueous toxicity of reaction solutions to Photobacterium Phosphoreum and Daphnia magna was rapidly decreased during ozonation. In addition, no obvious difference in the attenuation of TBBPA was found by ozone oxidation using different water matrices, and the effectiveness in natural waters further demonstrates that ozonation can be adopted as a promising technique to treat TBBPA-contaminated waters.

Effect of acid washing on pyrolysis of Cladophora socialis alga in microtubing reactor

Cladophora socialis is a unique macroalga that is widely grown in the coastal regions of Vietnam. In this work, the pyrolysis characteristics of C. socialis were evaluated using thermogravimetric analysis (TGA) and pyrolysis in a tubing reactor. Macroalgae have a high content of inorganic compounds. These compounds result in high char content during pyrolysis of the macroalgae, which degrades the quality of the product bio-oil. In order to study this effect, C. socialis was demineralized by acid washing to remove the inorganic compounds. The effect of acid washing on the pyrolysis product distribution and the selectivity of composition in pyrolysis oil was carefully investigated. The kinetic parameters and the primary reaction pathways were also determined based on experimental data using nonlinear least-squares regression assuming a first-order kinetics model.

Experimental and Theoretical Study of the Kinetics of the OH + Propionaldehyde Reaction between 277 and 375 K at Low Pressure.

Measurements of the rate constant for the reaction of OH radicals with propionaldehyde as a function of temperature were performed using low-pressure discharge-flow tube techniques coupled with laser-induced fluorescence detection of OH radicals. The measured room-temperature rate constant of (1.51 ± 0.22) × 10(-11) cm(3) molecules(-1) s(-1) at 4 Torr was generally lower but in reasonable agreement with previous absolute and relative rate studies at higher pressures. Measurements as a function of temperature resulted in an Arrhenius expression of (2.3 ± 0.4) × 10(-11) exp[(-110 ± 50)/T] cm(3) molecules(-1) s(-1) between 277 and 375 K at 4 Torr. The observed temperature dependence at low pressure is in contrast to previous measurements of a negative temperature dependence at higher pressures. Ab initio calculations of the potential energy surface for this reaction suggest that the primary reaction pathway involves the formation of a hydrogen-bonded prereactive complex, which could account for the difference in the observed temperature dependence at lower and higher pressures.

Investigation on the degradation of benzophenone-3 by UV/H2O2 in aqueous solution

Benzophenone-3 (BP-3), an organic ultraviolet (UV) filter, is reported to exhibit endocrine disruptive effects. In this study, the degradation of BP-3 by UV/H2O2 in aqueous solution was investigated by steady-state photolysis and laser flash photolysis experiments. The photolysis of BP-3 was not observed obviously after 8h under UV irradiation (λ=254nm), but the degradation of BP-3 could be conducted via UV/H2O2 due to the oxidation by hydroxyl radical (HO). At higher initial concentrations of BP-3, the degradation percentages decreased, and the optimal pH for the degradation of BP-3 was 6.0. The reaction of BP-3 and HO adhered to the pseudo-first-order kinetics. When the BP-3 concentration was 0.01mM, the rate constants of the apparent first-order reaction and second-order reaction between BP-3 and HO were 1.26×10−3s−1 and 2.97×1010M−1s−1, respectively. Several intermediate products were obtained and the primary reaction pathway of BP-3 and HO was proposed.

Understanding the Early Stages of the Methanol-to-Olefin Conversion on H-SAPO-34

Little is known on the early stages of the methanol-to-olefin (MTO) conversion over H-SAPO-34, before the steady-state with highly active polymethylbenzenium cations as most important intermediates is reached. In this work, the formation and evolution of carbenium ions during the early stages of the MTO conversion on a H-SAPO-34 model catalyst were clarified via 1H MAS NMR and 13C MAS NMR. Several initial species (i.e., three-ring compounds, dienes, polymethylcyclopentenyl, and polymethylcyclohexenyl cations) were, for the first time, directly verified during the MTO conversion. Their detailed evolution network was established from theoretical calculations. On the basis of these results, an olefin-based catalytic cycle is proposed to be the primary reaction pathway during the early stages of the MTO reaction over H-SAPO-34. After that, an aromatic-based cycle may be involved in the MTO conversion for long times on stream.

Quantum chemical investigation of the primary thermal pyrolysis reactions of the sodium carboxylate group in a brown coal model.

The primary pyrolysis mechanisms of the sodium carboxylate group in sodium benzoate-used as a model compound of brown coal-were studied by performing quantum chemical computations using B3LYP and the CBS method. Various possible reaction pathways involving reactions such as unimolecular and bimolecular decarboxylation and decarbonylation, crosslinking, and radical attack in the brown coal matrix were explored. Without the participation of reactive radicals, unimolecular decarboxylation to release CO2 was calculated to be the most energetically favorable primary reaction pathway at the B3LYP/6-311+G (d, p) level of theory, and was also found to be more energetically favorable than decarboxylation of an carboxylic acid group. When CBS-QBS results were included, crosslinking between the sodium carboxylate group and the carboxylic acid and the decarboxylation of the sodium carboxylate group (catalyzed by the phenolic hydroxyl group) were found to be possible; this pathway competes with unimolecular decarboxylation of the sodium carboxylate group. Provided that H and CH3 radicals are present in the brown coal matrix and can access the sodium carboxylate group, accelerated pyrolysis of the sodium carboxylate group becomes feasible, leading to the release of an Na atom or an NaCO2 radical at the B3LYP/6-311+G (d, p) or CBS-QB3 level of theory, respectively.

Ring-Opening and Oxidation Pathways of Furanic Oxygenates on Oxygen-Precovered Pd(111)

The surface reactivity of furan, furfural, and furfuryl alcohol on oxygen-precovered Pd(111) (O/Pd(111)) was studied via temperature-programmed desorption (TPD) and high-resolution electron energy loss spectroscopy (HREELS) to understand the oxidation processes of more complex alcohols and aldehydes. The primary reaction pathway explored was furfuryl alcohol dehydrogenation to furfural, followed by decarbonylation to furan and subsequent ring opening of furan through O–Cα scission; however, furfuryl alcohol and furfural also underwent other parallel reactions. At high coverages, deoxygenation of furfuryl alcohol to methylfuran was observed simultaneously with furfural production near 320 K, possibly through a disproportionation reaction of two alcohol adsorbates. Observation of furfural as a reaction product at this temperature was related to an increased prevalence of a weakly bound η1(O) aldehyde state near 250 K on O/Pd(111) as compared to clean Pd(111). Furfural also reacted with surface O to produce ...

Characterizing long-term CO2–water–rock reaction pathways to identify tracers of CO2 migration during geological storage in a low-salinity, siliciclastic reservoir system

Given the prevailing use of saline reservoirs for geological CO2 storage projects, limited data are available on the geochemical evolution of formation water chemistry during geological CO2 storage in low-salinity formations. The low-salinity (total dissolved solids<3000mg/L) middle to lower Jurassic sequence in Australia's Surat Basin has been characterized as a potential reservoir system for geological CO2 storage, comprising three major siliciclastic formations with distinctly different mineral compositions. Contrasts in the geochemical responses of Jurassic sequence core samples have been identified during short-term CO2–water–rock experiments conducted under CO2 storage conditions (Farquhar et al., in this issue). If persistent, such contrasts may serve as geochemical tracers of CO2 migration within the Surat Basin. Here we use a combined batch experiment and numerical modeling approach to characterize the long-term response of the Jurassic succession to storage and migration of CO2 and to assess reaction pathway sensitivity to CO2 partial pressure. Reservoir system mineralogy was characterized for 66 core samples from Geological Survey of Queensland stratigraphic well Chinchilla 4, and six representative samples were powdered and reacted with synthetic formation water and high-purity CO2 for up to 27days at a range of pressures. Formation water alkalinity offers limited buffering at elevated CO2 pressures and pH rapidly declines resulting in sustained enhancement of mineral dissolution rates. Batch reactor results exhibit regional groundwater-like 87Sr/86Sr values (0.7048–0.7066), less radiogenic than whole-rock results (>0.7085) indicating incongruent dissolution of the reservoir matrix. Carbonate and authigenic clay dissolution are expected to be the primary reaction pathways regulating long-term formation water composition during geological CO2 storage in the Surat Basin, with lesser contributions from dissolution of the clastic matrix.

Pressure-induced metallization of condensed phase β-HMX under shock loadings via molecular dynamics simulations in conjunction with multi-scale shock technique.

The electronic structure and initial decomposition in high explosive HMX under conditions of shock loading are examined. The simulation is performed using quantum molecular dynamics in conjunction with multi-scale shock technique (MSST). A self-consistent charge density-functional tight-binding (SCC-DFTB) method is adapted. The results show that the N-N-C angle has a drastic change under shock wave compression along lattice vector b at shock velocity 11km/s, which is the main reason that leads to an insulator-to-metal transition for the HMX system. The metallization pressure (about 130GPa) of condensed-phase HMX is predicted firstly. We also detect the formation of several key products of condensed-phase HMX decomposition, such as NO2, NO, N2, N2O, H2O, CO, and CO2, and all of them have been observed in previous experimental studies. Moreover, the initial decomposition products include H2 due to the C-H bond breaking as a primary reaction pathway at extreme condition, which presents a new insight into the initial decomposition mechanism of HMX under shock loading at the atomistic level.

Synthesis and characterisation of cement clinker-supported nickel catalyst for glycerol dry reforming

Glycerol dry reforming was performed in a packed-bed reactor containing 20 wt.% nickel catalyst employing CO2-to-C3H8O3 feed ratios of 0.6 ⩽ CGR ⩽ 5.0 and reaction temperatures between 923 and 1023 K for syngas (H2 and CO) production studies. Liquid N2 physisorption revealed a significant 32-fold increase in the Brunauer–Emmett–Teller (BET) specific surface area upon the incorporation of nickel metal onto the cement clinker support, which was also corroborated by field emission scanning electron microscopy (FESEM). In addition, NH3- and CO2-temperature programmed desorption (TPD) analyses exhibited the presence of a strong pair of acid (1061.4 μmol gcat−1) and basic (1.53 × 104 μmol gcat−1) sites on the catalyst. A bunsenite (NiO) species with a crystallite size of 15–18 nm and calcium silicate were successfully identified from the X-ray diffraction (XRD) pattern. Subsequently, the results appraised from the reaction studies confirmed the absence of a direct interaction between CO2 and the glycerol compound during the glycerol dry reforming and that the H2 was primarily produced from the glycerol decomposition. This finding could be ascribed to the chemisorption of both compounds at different active sites, which resulted in glycerol decomposition as the primary reaction pathway. The optimum condition for H2 production via glycerol dry reforming was at a carbon dioxide-to-glycerol ratio (CGR) of unity (at constant Pgly = 14 kPa) and 973 K. Moreover, the glycerol conversion ranged from 70% to 80% at a CGR of 1–1.67. Glycerol dry reforming was discovered to be more feasible for Fischer Tropsch synthesis, as the H2:CO product ratios were <2.0. The post-characterisation of the used catalysts confirmed the presence of whisker-type carbon, which fortunately can be easily removed via oxidation with O2.