Butanol Conversion Research Articles

Conversion of 1-butanol into High Value-Added Chemicals by Mixed Metal Oxides: The Influence of Co2+, Ni2+, and Zn2+ into Condensed Phase Products Distribution

Conversion of 1-butanol into High Value-Added Chemicals by Mixed Metal Oxides: The Influence of Co2+, Ni2+, and Zn2+ into Condensed Phase Products Distribution

An oxygen-assisted conversion of butanol to value-added products on nanocarbon catalysts: tuning product selectivity via nitrogen doping

The activity and mechanistic and kinetic analysis of nB conversion on NCNT were investigated, and the high ODH activity stems from the donated electrons from nitrogen to ketonic carbonyl groups.

Efficient Cross-Coupling of Acetone with Linear Aliphatic Alcohols over Supported Copper on a Fluorite-Type Pr2Zr2O7

In cross-coupling of biomass-derived acetone and alcohols contributing to the production of carbon-elongated chemicals and fuels, the essential catalyst components are metal dispersion for alcohol dehydrogenation and, more importantly, basicity for carbon–carbon coupling. Herein, we report the potential of co-precipitated praseodymia–zirconia solid solution (Pr2Zr2O7) as a support of Cu catalyst for the conversion of acetone and butanol into C7 and C11 products. Cu/Pr2Zr2O7 exhibits a high yield of C7 and C11 (ca. 84%) compared to Cu/ZrO2 and Cu/PrO1.83. Moreover, it is robust under the employed solvent-free conditions owing to a solid solution of Pr2Zr2O7 compared to PrO1.83 showing phase transition to PrOHCO3. It is also tolerant to up to 5 wt % water of the reactant mixture, recyclable once adequate post-treatment is employed after the reaction, and can convert the acetone–butanol–ethanol mixture into C5–C11 products at the nearly equivalent yield (82%) to the acetone–butanol mixture. Therefore, the Cu/Pr2Zr2O7 reported herein is an efficient catalyst for the coupling of acetone with linear aliphatic alcohols into biofuel precursors.

Conversion of butanol to propene in flow: A triple dehydration, isomerisation and metathesis cascade

A combined three-step flow cascade conversion of n-butanol to propene is demonstrated. Zeolite H-ZSM-5 gives high conversion in the initial n-butanol dehydration step (98%). Subsequent isomerisation of terminal butenes to internal butenes over zeolite H-Fer takes place with good conversion (87%). Finally, cross-metathesis with ethene over a tungsten on acid-washed SiO2/Al2O3 catalyst affords propene with good selectivity (65%). Coupling these three steps into a single flow sheet gives an overall yield of 64% propene from n-BuOH. Ethene cross-metathesis catalyst performance was probed using 2-pentene as a model co-substrate giving good conversion (~90%) and moderate selectivity to butenes (67%).

Selective dehydration of 1-butanol to butenes over silica supported heteropolyacid catalysts: Mechanistic aspect

Butenes are considered as important olefinic building block to produce fuels/fuel additives and commodity chemicals. In the present investigation, selective dehydration of 1-butanol to butenes was studied in a continuous-flow fixed-bed reactor using various silica-supported heteropolyacid (HPA) catalysts such as phosphotungstic acid (PTA), silicotungstic acid (STA), phosphomolybdic acid (PMA), and silicomolybdic acid (SMA) as the solid acid catalysts. The physicochemical properties of these HPA were determined by BET, powder XRD, FTIR, NH3-TPD, and Py-FTIR. The acid strength and Brønsted/Lewis (B/L) acid ratio were increased with higher loading of HPA on silica. The nature of HPA (addenda and hetero atom) and loading of HPA are important factors for the dehydration of 1-butanol and selectivity towards butenes. PTA and STA showed superior catalytic activity than PMA and SMA. The reaction temperature and WHSV also strongly affected the butanol conversion and selectivity of butenes. The selectivity of di-n‑butyl ether decreases with the rising temperature from 523 K to 623 K. The isomerization of 1-butene leading to the formation of other butene isomers depends on the HPA loading, temperature, and WHSV. The presence of molybdenum addendum atom in PMA and SMA promotes dehydrogenation and hydrogenation, leading to the formation of various light hydrocarbons. The 20PTA/SiO2 catalyst afforded 99.8% selectivity towards butenes at quantitative conversion of 1-butanol, whereas the 20STA/SiO2 catalyst gave nearly 97.0% conversion of 1-butanol and 99.9% butenes selectivity at 673 K, 37.4 h−1 of WHSV.

Oxygen assisted butanol conversion on bifunctional carbon nanotube catalysts: Activity of oxygen functionalities

Catalytic conversion of n-butanol to high-value-added product is considered as a highly important route towards biomass derived fine chemicals. The present work reports the applications of non-metallic multi-walled carbon nanotube (CNT) as bifunctional catalysts for oxygen assisted n-butanol conversion reactions. Oxidative dehydrogenation (ODH) and dehydration of n-butanol on CNT yielded aldehyde and alkene compounds via redox and acid catalytic routes, respectively. CNT exhibited high activity (over 50% n-butanol conversion) and stability (over 120 h) under gentle reaction conditions (<330 °C), which are competitive to conventional metal-based catalysts. Carboxylic acid groups were identified as catalytic active sites for dehydration reactions via linking the reactivity (kinetic parameters) with the surface composition and structural information of CNT catalysts. The redox activity could be related to ketonic carbonyl groups, and interestingly the intrinsic ODH catalytic activity is also influenced by degree of graphitization for CNT materials.

Effect of the surface properties of Me2+/Al layered double hydroxides synthesized from aluminum saline slag wastes on the adsorption removal of drugs

This work presents the synthesis of Me 2+ (Co, Mg, Ni and Zn)/Al layered double hydroxides (LDH) with a 3:1 M ratio by the co-precipitation method. Structural characterization and comparison of the series has been achieved using powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), nitrogen physisorption at 77 K, thermogravimetry measurements (TGA), temperature-programmed reduction (TPR), X-ray photoelectron spectroscopy (XPS), ammonia temperature-programmed desorption (NH 3 -TPD) and point of zero charge (pHpzc). Batch experiments were performed to analyze the adsorption capacity of the different LDH on diclofenac and salicylic acid, as example of emergent pollutants. The pH, mass of adsorbent, contact time and concentration of pollutant were the parameters used to compare the adsorption performance of the synthesized materials. Samples showed different behavior and the equilibrium was reached at different times, Mg 6 Al 2 and Zn 6 Al 2 showed lower equilibrium times but had higher adsorption capacity. Various adsorption and isotherm equation models were employed to study both the kinetic and equilibrium results and, in general, the removal of diclofenac was greater than that of salicylic acid. 1-Butanol conversion was also used as a means of acidity and basicity characterization and the results were compared with the adsorption performance of the samples in order to explain the results found. A relationship between the amount of pollutants adsorbed and the butenes formed in the dehydrogenation reaction of 1-butanol was found. • (CoMgNiZn)/Al-hydrotalcites from saline slags wastes were prepared by the co-precipitation method. • (CoMgNiZn)/Al-hydrotalcites were used as adsorbents of diclofenac and salicylic acid. • 1-Butanol conversion was used as a means of acidity and basicity characterization. • The catalytic performance was compared with the adsorption capacity to explain the results found.

Influence of the Catalyst Particle Size on the Aqueous Phase Reforming of n-Butanol Over Rh/ZrO2.

Butanol is a by-product obtained from biomass that can be valorized through aqueous phase reforming. Rh/ZrO2 catalysts were prepared and characterized, varying the size of the support particles. The results showed a relatively mild effect of internal mass transport on butanol conversion. However, the influence of internal transport limitations on the product distribution was much stronger, promoting consecutive reactions, i.e., dehydrogenation, hydrogenolysis, and reforming of propane and ethane. Hydrogen consuming reactions, i.e., hydrogenolysis, were more strongly enhanced than hydrogen producing reactions due to internal concentration gradients. Large support particles deactivated faster, attributed to high concentrations of butyraldehyde inside the catalyst particles, enhancing deposit formation via aldol condensation reactions. Consequently, also the local butyric acid concentration was high, decreasing the local pH, enhancing Rh leaching. The influence of internal transfer limitation on product distribution and stability is discussed based on a reaction scheme with three main stages, i.e., (1) formation of liquid intermediates via dehydrogenation, (2) formation of gas via decarbonylation/decarboxylation reactions, and (3) hydrocarbon hydrogenolysis/reforming/dehydrogenation.

Upgrading 1-butanol to unsaturated, carbonyl and aromatic compounds: a new synthesis approach to produce important organic building blocks

Conversion of 1-butanol into added-value organic building blocks was achieved using fixed-bed flow reactor and Cu-based catalyst at 550 and 600 °C with and without methanol as addictive.

Renewable hydrogen production by steam reforming of butanol over multiwalled carbon nanotube-supported catalysts

The conversion of bio-oxygenates into hydrogen (H2) via catalytic steam reforming is a green approach for H2 generation. In the present work, butanol was chosen as renewable feedstock for producing H2. Two catalysts supported on multiwalled carbon nanotubes, Ni/CNT and Co/CNT, were synthesized by the wetness impregnation method and used for butanol reforming. Trials were performed in a fixed-bed reactor in the 623–773 K range using S/C ratio equal to 33.3 mol/mol (here, S/C denotes steam to carbon ratio). The Ni/CNT catalyst exhibited higher reforming activity. The best catalytic performance for Ni/CNT was observed at T = 773 K. At this temperature, high values of butanol conversion (87.3%) and H2 yield (0.75 mol/mol) were observed at W/FA0 = 16.7 g h/mol (here, W is the catalyst mass and FA0 is the molar flow rate of butanol at the inlet). The performance of Ni/CNT catalyst for steam reforming of synthetic bio-butanol was also investigated at T = 773 K and H2 yield of 0.65 mol/mol was achieved.

A study on the efficacy of noble metal catalysts for butanol steam reforming

Biomass-derived oxygenates such as biobutanol are potential candidates for renewable hydrogen (H2) production. In this work, the model compound butanol was chosen as feed for H2 production. Steam reforming of butanol was investigated at mild temperatures (623–773 K) over two noble metal catalysts Pt/Al2O3 and Pd/Al2O3 renowned for their reforming activity. Trials were performed in a fixed-bed reactor using 1–4 wt% butanol solutions as feedstock. At T = 773 K and W/FA0 = 166.8 g h/mol (here, W and FA0 denote mass of catalyst and molar flow rate of butanol in the feed), butanol conversion was almost complete over both catalysts. However, turnover frequency observed over Pt/Al2O3 (TOFH2 = 45.5 min−1) was higher than that achieved using Pd/Al2O3 (TOFH2 = 21.3 min−1). The apparent energy of activation for the disappearance of butanol over Pt/Al2O3 and Pd/Al2O3 was found to be 22.9 and 30.2 kJ/mol respectively. Thus, this work has provided key insights into H2 production from butanol using noble metals at mild reaction conditions.

Esterification over Acid-Treated Mesoporous Carbon Derived from Petroleum Coke.

Multistep activation of a Canadian oilsands petroleum coke that yields an acidified mesoporous carbon catalyst is reported. Microporous-activated carbon (APC; ∼2000 m2/g), obtained by thermochemical activation of petroleum coke using KOH, was impregnated with ammonium heptamolybdate and activated by carbothermal hydrogen reduction (CHR). The resulting Mo2C, supported on high-mesopore volume (Vmeso ∼0.4 cm3/g) carbon, yields the desired mesoporous carbon catalyst (Vmeso ∼0.7 cm3/g) following acid washing. The effect of CHR temperature and the benefit of Mo2C loading on mesopore development is reported, and pore development models are discussed. The mesoporous carbons are active for the esterification of acetic acid and 1-butanol at 77 °C, and the butanol conversion correlates with the catalyst acidity, as measured by NH3-TPD.

Reactive thermal hazards of irradiated tributyl phosphate with nitric acid

Red oil incidents reported worldwide are attributed to the reactive thermal reactions between Tributyl phosphate (TBP) and nitric acid. The vigor of thermal behavior may be influenced by various factors including irradiation, presence of metal nitrates etc. This work is focused to study the influence of irradiation on the reactive thermal behavior of 30% TBP with varying strengths of HNO3 for the first time. The Accelerating Rate Calorimetry (ARC) studies reveal that irradiated 30% TBP reacts exothermically with 4 mol/L–16 mol/L HNO3 and contributes to rise in system pressure. A lower onset temperature for exothermic reaction was noticed in irradiated TBP compared to the non-irradiated 30% TBP with acid. From the Zero-Order kinetic model, the TMRad for irradiated and non-irradiated TBP 4 mol/L HNO3 system was been determined for thermal hazard assessment. FT-IR, NMR and GC–MS characterization of the residues of ARC clearly suggest that conversion of butanol to butanoic acid is the exothermic red-oil forming reaction.

Selective conversion of butanol into liquid branched olefins over zeolites

The n-butanol to hydrocarbon (BTH) reaction can produce a series of valuable chemicals and clean fuel precursors. The BTH reaction over different zeolite catalysts (ZSM-5, ZSM-22, Meso-ZSM-22, and ZSM-35) with an emphasis on the production of liquid branched olefins which can be used as precursors for clean gasoline was investigated in this paper. It was found that the structure and acidity of zeolite significantly influences the product distribution in BTH reaction. ZSM-5 zeolite with medium micropore size and large intersections, which are not present in ZSM-22, led to aromatic-rich products and had a long lifetime. ZSM-22 and Meso-ZSM-22 zeolites with unidirectional 10-ring structure achieved a high selectivity to isobutylene and C5+ branched hydrocarbons. Moreover, the Meso-ZSM-22 obtained by desilication with a higher acidity density and improved diffusion property resulted in more liquid organic products than the parent ZSM-22. ZSM-35 exhibited a high product-shape-selectivity for producing isobutylene because of its unique irregular sheet structure and is not suitable for liquid olefin production.

Kinetic investigation on butanol steam reforming over Ru/Al2O3 catalyst

Steam reforming of biomass-derived oxygenates is an attractive technique for the renewable production of hydrogen (H2). In this work, steam reforming of n-butanol – a representative of bio-oxygenates – was studied over commercial 5% Ru/Al2O3 catalyst in a fixed-bed reactor. Kinetics of butanol reforming was investigated between temperatures 623 and 773 K at steam/carbon (S/C) ratio equal to 33.3 mol/mol. The W/FA0 ratio (W: mass of catalyst, FA0: molar flow rate of butanol in feed) was varied between 3.3 and 16.7 g h/mol. At T = 773 K, butanol conversion and H2 yield were 93.4% and 0.61 mol/mol. Evaluation of the kinetic data showed that reaction order with respect to butanol was unity. The activation energy for the investigated reaction was 78 kJ/mol. Finally, a Langmuir-Hinshelwood model that assumed the surface reaction between the adsorbed reactants as rate-determining was used to describe the kinetic data.

Study of butanol conversion to butenes over H-ZSM-5: Effect of chemical structure on activity, selectivity and reaction pathways

To evaluate the viability of the use of butanol as a green chemical key molecule, the effects of temperature and site time on the transformation of the three butanol isomers, 1-butanol, 2-butanol and iso-butanol, towards butenes over H-ZSM-5 have been studied in search of the most promising isomer. Under dehydration conditions, 2-butanol is by far the most active and intermediate ether formation is only observed for 1-butanol. On the other hand, only isobutanol allows the direct formation of isobutene, the most valuable of the butene isomers. Hence, it is especially interesting to further stimulate the biomass derived isobutanol production, e.g. via genetic modification of appropriate microorganisms, in order to allow thereafter the formation of green drop-in isobutene upon dehydration with H-ZSM-5 in existing refineries. Due to the large potential of isobutanol, a reaction path analysis via ab-initio based microkinetic simulations is conducted for this molecule. Comparing these results with simulations on 1-butanol indicates that the shift is occurring due to a shift of the dominant reaction pathway towards the direct dehydration via anti elimination. A Gibbs free energy analysis shows that the large distortion of the transition state for isobutanol etherification renders this path far less favorable, resulting in the lack of formation of the di-alkyl ether, whilst the increased degree of substitution of the alkyl chain in isobutanol is found to promote the direct dehydration path, leading to an increase of the overall activity of isobutanol as compared to 1-butanol.

Studies of tert-Butanol Dehydration over Sulfocationic Catalysts at Concurrent of Liquid and Vapour Flows

The experimental results on tert -butanol dehydration are discussed. The influence of the catalyst bed temperature, water content in the feed flow, and the temperature of the feed flow on the tert -butanol conversion was experimentally studied in the presence of the KU-2FPP and Purolite СТ275 catalysts. The isobutylene yield was established to depend mainly on the heat supply to the reaction zone. The countercurrent flows of the phases through the catalyst bed were shown not to allow the process to be intensified using a more active catalyst. It was experimentally demonstrated that the arrangement of downward concurrent flows in the catalyst bed led to an increase in the efficiency of tert -butanol decomposition over a more active Purolite CT275 catalyst.

Studies of Thermal Conversion of Acetonelignin in Supercritical Butanol in the Presence of NiCuMo/SiO2 Catalysts

Both industrially implemented and developed technologies for chemical wood processing are aimed at preferable transformation of the cellulose component into target products, while effective methods for processing of lignin, a bulky waste, are as yet unavailable. The present study was focused on the influence of NiCuМо/SiO 2 catalysts on thermal transformations of acetonelignin in the superctirtical butanol medium at 280, 300, 350 °C. Chromatomass spectrometric and 13 C NMR spectroscopic techniques were used for characterization to the liquid products. Thermochemical transformations of butanol were not observed at the temperature below 300 °C. The butanol conversion was increased up to 36–40 wt % in the presence of the catalysts. In the presence of the NiCuМо/SiO 2 catalysts at 300 °C, the yield of hexane-solluble products of acetonelignin thermotransformations increased by factor of 2.4, while the solid residue yield was factor of 3.3 decreased. Under these conditions, the proportion of methoxyphenols, including syringol, in the hexane-soluble products was factor of 14 lower. 13 C NMR data indicated that the catalytic transformations of acetonelignin into acetone-soluble liquid products are accompanied by the cleavage of β–O–4 bonds between structural elements of lignin and by a decrease in the content of methoxyl groups predominantly in syringal structural units of the products formed.

Effect of zeolite confinement on the conversion of 1-butanol to butene isomers: mechanistic insights from DFT based microkinetic modelling

First principles microkinetic modelling shows that, unlike in H-ZSM-5 and H-ZSM-22,trans-2-butene formation in H-FER occursviadirect dehydration of 1-butanol.

Mechanistic insights into the formation of butene isomers from 1-butanol in H-ZSM-5: DFT based microkinetic modelling

First principles microkinetic modelling provides in-depth mechanistic insights into the competing reaction pathways for zeolite-catalyzed conversion of 1-butanol to butene isomers.