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N-butanol, a volatile organic compound prevalent in numerous industrial processes, poses significant risks to human health and the environment if not properly monitored. Consequently, the development of high-sensitivity n-butanol sensors is imperative. For this reason, NdFeO 3 nanoparticles were successfully synthesized by hydrothermal method and used for the detection of n-butanol. They were fully analyzed using characterization techniques such as XRD, BET, EDX, SEM, TEM and XPS. The test results revealed that the prepared samples exhibited a granular structure with an average diameter of approximately 65 nm. The specific surface area measured 15.415 m2/g, and the pore size was determined to be 16.638 nm. The NdFeO 3 sensor responds up to 441 for 100 ppm n-butanol at 260 °C, response and recovery times were 33 s and 7 s respectively. The response value of the NdFeO 3 sensor is still 4.3 for 1 ppm n-butanol with a minimum detection limit of 0.024 ppm. Simultaneously, the NdFeO 3 sensor has excellent selectivity, stability and moisture resistance. These good sensing properties indicate that this work provides a possible strategy for developing an economical and repeatable high performance gas sensor for the detection of n-butanol. [ABSTRACT FROM AUTHOR]

Being one of toxic and flammable volatile organic compounds (VOC), n-butanol has brought about many potential health risks, there is an urgent demand for highly sensitive detection techniques to monitor its concentration in occupational environments and the air. In this paper, Ce-doped MOF:ZnO sensors under UV activation for room-temperature detection of n-butanol were synthesized by the co-precipitation method and systemically characterized by XRD, SEM, HRTEM, and XPS. The sensitive performances were evaluated by the use of a WS-30A gas sensor measurement system. The results showed that Ce doping has significantly enhanced the sensitivity of the MOF:ZnO sensors, and the response value of the 0.08 % Ce-doped ZnO sensor has achieved to 397.30, which was 9.32 times higher than that of the pristine MOF:ZnO. And the response and recovery times were 17 and 117 s respectively, demonstrating a speedy detection capability. In addition, the sensor gained excellent stability and reproducibility with special selectivity for n-butanol. The comprehensive achievements of this research would be promising to promote the development of volatile organic compound detection technology and beneficial to the well application in the fields of environmental monitoring, industrial safety, and public health. [ABSTRACT FROM AUTHOR]

In this experiment, PrFeO 3 -In 2 O 3 nano-composites were prepared by electrospinning and hydrothermal approach. In particular, the PrFeO 3 -In 2 O 3 material has a rough surface, which can enhance the contact area with the gas, and further analysis shows that the band gap of the PrFeO 3 -In 2 O 3 material is reduced compared with the pure In 2 O 3 material. Compared with pure In 2 O 3 , PrFeO 3 -In 2 O 3 composite has better sensing performance for n-butanol. The results show that the PrFeO 3 -In 2 O 3 based sensor has remarkable gas sensing performance for n-butanol gas. Especially the response to 100 ppm n-butanol is as high as 95.98 at 190 °C, and good repeatability. In addition, the response of PrFeO 3 -In 2 O 3 based sensor shows a good linear relationship with the concentration,n-butanol gas can be quantitatively measured.In this work, X-ray diffraction (XRD), X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), atomic force microscopy (AFM), specific surface area testing (BET), and UV–Vis spectroscopy were used to characterize the materials. [ABSTRACT FROM AUTHOR]

N-butanol is well known to be a flammable and harmful liquid that is a potential threat to human health and property. Therefore, it is important to monitor the concentration of n-butanol in the surroundings. The need for highly efficient toxic gas detection is urgent and has been driving the research on gas sensors for practical applications. Molybdenum disulfide (MoS2) has been attracting significant interest for gas detection at room temperature. Herein, we report biofunctionalized magnetic nanoparticles incorporated MoS2 for sensing n-butanol. The biosynthesized magnetite nanoparticles (CT-Fe3O4) were synthesized by the addition of Cinnamomum Tamala (CT) leaf extract, and subsequently, the nanocomposite was synthesized using a hydrothermal method. Highly sensitive sensors based on MoS2-CT-Fe3O4 were fabricated and tested for sensing different concentrations of n-butanol. The nanocomposites showed a good sensing performance (Δ R/Rair %) of 72% towards 20 ppm of n-butanol, indicating the potential use of MoS2-CT-Fe3O4 nanocomposite for sensing n-butanol at room temperature. [ABSTRACT FROM AUTHOR]

The catalytic relevance of different surface functionalities present on hydrotalcite‐derived Mg−Al mixed metal oxides (MgAlO) are investigated in the context of ethanol upgrade to n‐butanol. The catalyst structure and active sites were altered through changes in the Mg/Al ratio and introduction of additional redox metal oxide functionalities. After performing a series of catalytic activity tests, operando FTIR characterization, TGA measurements and in situ active center titration; qualitative and quantitative relationships between catalyst structure and catalytic performance are obtained. We found the Mg−Al mixed metal oxides system can catalyze the ethanol to n‐butanol process through a Guerbet reaction pathway, though the process is kinetically limited. By introducing redox active metal oxides to the catalyst formulation, such as MoO3 or V2O5, this problem can be partially solved, but at a cost of losing a significant fraction of high‐strength basic centers which are the most catalytically relevant function in the system, as they control enolate formation rates leading to the C−C coupling step required for n‐butanol formation. [ABSTRACT FROM AUTHOR]

In this work, La-doped CdS composites with sparse pine-dendritic morphology were prepared using a convenient one-step hydrothermal method and tested for their gas-sensitive properties. Compared with the pure CdS-based sensor, the sensor L-3 (containing 3 mol% of La) demonstrated a noticeable increase in gas-sensitive performance to n-butanol, exhibiting the response value as high as 127 for 100 ppm n-butanol gas at 200 °C. Besides the fast recovery rate (only 2 s) for n-butanol, the device possessed good selectivity and repeatability, as well as excellent long-term stability. After a series of characterization via XRD, SEM, TEM, XPS and BET, it was established that the enhancement of the gas-sensitive performance might be related to the introduction of La ions, the electron sensitization effect, and the increase in the specific surface area. [ABSTRACT FROM AUTHOR]

Catalysts based on KL-zeolite exchanged with alkali metal ions (Rb+ and Cs+) were studied for conversion of ethanol to oligomerization through the Guerbet reaction pathway. The catalysts were characterized by techniques such as ICP-AES, FESEM-EDX, N2-adsorption-desorption, and CO2-TPD to assess their physio-chemical properties. Effects of operating parameters, namely reaction temperature, pressure, and feed flow rate on catalytic activity for the conversion of ethanol to n-butanol were examined. Furthermore, influence of alkali metal loading on KL-zeolite was explored. Substantial ethanol conversion (42.6%) and n-butanol yield (13.9%) were achieved at 450°C and 30 kg/cm2 after a 6 h reaction employing Cs-KL zeolite catalyst. Observations indicated that the butanol selectivity is highest among the reported literature. Additionally, this catalyst has exhibited low deactivation rate attributable to coke formation. Spent catalysts were studied for XRD and DTG/TGA analysis. Present investigation establishes that KL-zeolite, particularly when modified with alkali metal ions, proves to be an efficient catalyst for the Guerbet conversion of ethanol, highlighting its potential for ethanol upgrading. [ABSTRACT FROM AUTHOR]

In this paper, we studied the alcohol-sensing properties of CoMn2O4 nanoparticles for the first time. The CoMn2O4 nanoparticles were prepared via a simple microwave-assisted colloidal method using cobalt nitrate, manganese nitrate, dioctyl sulfosuccinate sodium salt, and ethylene glycol as a solvent. Various techniques were used to characterize the structural, morphological, and optical properties of CoMn2O4. The crystal structure of CoMn2O4 was found after calcination at a temperature of 400 °C. The Raman spectrum showed seven vibrational bands, while the optical absorption spectrum showed three bands, confirming the spinel CoMn2O4. Morphological analysis revealed that the porous microstructure of CoMn2O4 was composed of nanoparticles with a size distribution of 16 to 58 nm. Gas sensors were fabricated with the CoMn2O4 powders calcined at 400 °C using the brush-coating method, and experimental results showed that CoMn2O4 nanoparticles were more sensitive to n-butanol than isopropanol and ethanol at an operating temperature of 185 °C. The CoMn2O4 sensor showed a response of 6.6 at 50 ppm n-butanol with good stability, reproducibility, and repeatability. The present article provides a new sensing material that could be used as an n-butanol sensor with significant benefits for human health. [ABSTRACT FROM AUTHOR]

Abstract N-butanol is well known to be a flammable and harmful liquid that is a potential threat to human health and property. Therefore, it is important to monitor the concentration of n-butanol in the surroundings. The need for highly efficient toxic gas detection is urgent and has been driving the research on gas sensors for practical applications. Molybdenum disulfide (MoS2) has been attracting significant interest for gas detection at room temperature. Herein, we report biofunctionalized magnetic nanoparticles incorporated MoS2 for sensing n-butanol. The biosynthesized magnetite nanoparticles (CT-Fe3O4) were synthesized by the addition of Cinnamomum Tamala (CT) leaf extract, and subsequently, the nanocomposite was synthesized using a hydrothermal method. Highly sensitive sensors based on MoS2-CT-Fe3O4 were fabricated and tested for sensing different concentrations of n-butanol. The nanocomposites showed a good sensing performance ( $$\Delta$$ Δ R/Rair %) of 72% towards 20 ppm of n-butanol, indicating the potential use of MoS2-CT-Fe3O4 nanocomposite for sensing n-butanol at room temperature.

The efficient detection of n-butanol, which is in demand for highly sensitive materials, is essential for multiple applications. A nonaqueous method was applied to prepare NiFe2O4 nanoparticles (NPs) using benzyl alcohol as a solvent, which shows a size of 7.9 ± 1.6 nm and a large surface area of 82.23 m2/g. To further improve the sensing performance for n-butanol, Pd/PdO functionalization was sensitized with NiFe2O4 NPs. Gas sensing results demonstrate that the Pd/PdO-NiFe2O4 exhibits an enhanced response of 36.9 to 300 ppm n-butanol and a fast response and recovery time (18.2/17.6 s) at 260 °C. Furthermore, the Pd/PdO-NiFe2O4-based sensor possesses a good linear relationship between responses and the n-butanol concentration from 1 to 1000 ppm, and great selectivity against other volatile organic compounds (VOCs). The excellent sensing enhancement is attributed to the catalytic effects of Pd/PdO, the increase of oxygen vacancies, and the formation of heterojunction between PdO and NiFe2O4. Thus, this study offers an effective route for the synthesis of Pd/PdO-functionalized NiFe2O4 NPs to achieve n-butanol detection with excellent sensing performance. [ABSTRACT FROM AUTHOR]

New challenges posed to internal combustion engines require a fresh approach and the application of modern simulation methods. This study focuses on the numerical analysis of the co-combustion process of diesel fuel with butyl alcohol in a dual-fuel, self-ignition internal combustion engine based on a three-dimensional engine model developed in AVL Fire software. The influence of butanol content, ranging from 0 to 60 %, on engine performance and emissions was investigated. Increasing the amount of butyl alcohol burned with diesel fuel leads to a delay in ignition, decreases maximum cylinder pressure and temperature, and increases the rate of pressure rise and heat release rate. For alcohol content of 20 % and 40 %, there is an increase in pressure and indicated power compared to diesel fuel alone. The addition of butanol to diesel fuel reduces the specific emissions of nitrogen oxides and Soot in the dual-fuel engine. The most favorable case was with a 40 % butanol content. For DB40, the highest IMEP (0.69 MPa) and Ni (10.37 kW) values were obtained, along with the highest TE efficiency (43.64 %). In comparison to D100, lower NO and Soot emissions were achieved for this case by 35 % and 65 % respectively. [ABSTRACT FROM AUTHOR]

The adsorption/desorption of n-butanol and butyl acetate on the SiO2 surface was studied experimentally by thermokinetic spectrometry and computer molecular dynamic (MD) simulations (temperature, energy, and structural characteristics of adsorption). Radial distribution function (RDF) profiles were constructed and analyzed based on the MD modeling data for the "surface (SiO2)–carrier gas (Ar)–target molecule (n-butanol/butyl acetate)" ternary system at three temperatures of the system: T = 300, 500, and 700 K. A comparative analysis of the results suggests that the addition of an acetate group enhances the affinity of the butyl acetate molecule for the SiO2 surface. Consequently, the adsorption of butyl acetate occurs more completely at higher temperatures compared with the adsorption of n-butanol. In addition, changes in the size influence the atomic arrangement in the butyl acetate molecule relative to the SiO2 surface atoms, leading to the observed "displacement" of the carbon skeleton atoms of the ( – – – – ) chain for both (n-butanol and butyl acetate) molecules. According to the experimental data on n‑butanol and butyl acetate desorption from the SiO2 surface in the n-butanol/SiO2/argon (butyl acetate/SiO2/argon) ternary system, the activation energy of desorption is 78.83 (87.58) kJ/mol, and the pre-exponential factor is 4.41 × 107 (1.81 × 1010) s–1. [ABSTRACT FROM AUTHOR]

The combustion characteristics of spark assistant compression ignition mode under different loads and fuels were explored, as well as by constructing artificial neural networks(ANN) model, the prediction ability of different algorithms for engine performance was discussed. Burning methanol and n-butanol can help to improve IMEP and induce earlier spontaneous combustion. The knock intensity(KI) of engine fueled with methanol was highest followed by n-butanol and gasoline, but maximum amplitude of filtered pressure oscillation(MAPO) shows the opposite trend. KI showed great positive liner correlation with ignition timing. Methanol showed the most outstanding tolerance on the compression ignition state. Fueled with methanol can decreased equivalent brake specific fuel consumption(ESFC) up to 52.9 % compared with the initial SI gasoline engine. N-butanol can improve BSNOx, BSTHC and BSCO concurrently, however fueled with methanol will worsen BSNOx. ANN model for engine combustion, economy and emissions performance was built. The prediction accuracy of Bayesian regularization algorithm for engine performance predicting was highest, but it have no advantage in the calculating times when the amount of data was large while the Levenberg-Marquardt algorithm would be the ideal efficient. The mean square error of ESFC and emissions parameters under scaled conjugate gradients algorithm always poorest.

The primary aim of this research study was to examine the effectiveness and environmental consequences of using Delonix regia biodiesel (DRB) in combination with butanol (BUT), exhaust gas recirculation (EGR), and diesel fuel (D) on a direct injection compression ignition engine operating at a constant speed. This study involved the formulation of five distinct biodiesel blends, namely DRB10% + D90%, DRB20% + D80%, DRB10% + BUT10% + D80%, DRB10% + BUT20% + D70%, and DRB20% + D80% + EGR10%. The inclusion of n‐butanol in a biodiesel blend serves to tackle the problem of inadequate combustion in fuel blends by alleviating the oxygen deficiency that occurs during the combustion process. The findings of the study revealed that the combination of DRB at 10%, BUT at 20%, and D at 70% produced in a significant reduction in specific fuel consumption (SFC) by 11.19% and brake thermal efficiency by 2.62%. Additionally, this combination led to a decrease in exhaust emissions of CO and Smoke, with the exception of HC and NOx, when compared to the use of diesel fuel. The control of HC and NOx emissions can be achieved through the implementation of an exhaust gas recirculation system. The results of this investigation suggest that Delonix regia biodiesel, in combination with a 20% concentration of n‐butanol, has potential as a viable alternative fuel choice that may be utilized without necessitating any engine modifications. [ABSTRACT FROM AUTHOR]

Present study involves the investigation of the esterification kinetics between butyric acid and n‐butanol. This reaction was conducted in a batch reactor, utilizing homogeneous methanesulfonic acid (MSA) catalyst. Response surface methodology (RSM) was conducted prior to the kinetic study using "Design Expert; version‐11.0" for finding the causal factors influencing the conversion of butyric acid. Most important factors identified with their limits against conversions (during optimization of the process using RSM) were taken up to critically analyze the effect of them on butyric acid conversion. Concentration and activity‐based model of the process were proposed assuming second order reversible reaction scheme using homogeneous MSA catalyst. During the study of non‐ideal behavior of the system, UNIFAC model was adapted for assessing the activity coefficients of species present in equilibrated liquid phase. Experimental data were used to evaluate kinetic and thermodynamic parameters such as rate constants, activation energy, enthalpy, and entropy of the system. The endothermic nature of esterification was confirmed by positive value of enthalpy obtained. The effect of various levels of causal variables like temperature (60–90°C), catalyst concentration (0.5–1.5 wt.%), and molar ratio of n‐butanol to butyric acid (1–3) on conversion kinetics of butyric acid was investigated during transient and equilibrium phase of the reaction. It has been observed that molar ratio of butanol to butyric acid has the highest influence on the conversion. The rate equation derived offered a kinetic and thermodynamic framework to the generated data. It also exhibits a notable degree of conformity of predicted data to the experimental ones and effectively characterizes the system across different reaction temperatures, reactant molar ratio, and catalyst concentration. [ABSTRACT FROM AUTHOR]

The permeability–selectivity trade‐off of membrane is a major challenge limiting the development of pervaporation (PV) technology. Rational design of high‐performance mixed matrix membranes (MMMs) has the potential to break off the trade‐off. Herein, a solvent‐assisted linker exchange‐based strategy is reported to introduce fluoroalkyl into metal–organic framework‐808 (MOF‐808). The pore size of fluorinated MOF‐808 can be adjusted with fluoroalkyl of different chain length (like trifluoromethyl and pentafluoropropyl). Then, the fluorinated MOF‐808/polyether block amide (PEBA) MMMs are prepared for the PV of n‐butanol/water. Compared with pristine PEBA membrane, 20 wt% 3F‐MOF‐808(P)/PEBA MMMs (3F = ‐CF3 group; P = postmodification method) exhibit 69% increase in permeation flux and 33% increase in separation factor in the PV of 2.5 wt% n‐butanol aqueous solutions at 70 °C. Based on Grand Canonical Monte Carlo and molecular dynamics simulations, fluorinated MOF‐808 shows better butanol affinity (pull effect) and stronger water repulsion ability (push effect). And the "push–pull effect" between fluorinated MOF‐808 with butanol/water is helpful to enhance the PV performance of MMMs. The application of "push–pull effect" provides a new strategy for the rational design of high‐performance MMMs, which is of great significance for the in‐depth research and application of PV technology. [ABSTRACT FROM AUTHOR]

N-butanol (C4H9OH) is a volatile organic compound (VOC) that is susceptible to industrial explosions. It has become imperative to develop n-butanol sensors with high selectivity and fast response and recovery kinetics. CdS/Ag2S composite nanomaterials were designed and prepared by the solvothermal method. The incorporation of Ag2S engendered a notable augmentation in specific surface area and a consequential narrow band gap. The CdS/Ag2S-based sensor with 3% molar ratio of Ag2S, operating at 200 °C, demonstrated a remarkably elevated response (S = Ra/Rg = 24.5) when exposed to 100 ppm n-butanol, surpassing the pristine CdS by a factor of approximately four. Furthermore, this sensor exhibited notably shortened response and recovery times, at a mere 4 s and 1 s, respectively. These improvements were ascribed to the one-dimensional single-crystal nanorod structure of CdS, which provided an effective path for expedited electron transport along its axial dimension. Additionally, the electron and chemical sensitization effects resulting from the modification with precious metal sulfides Ag2S were the primary reasons for enhancing the sensor response. This work can contribute to mitigating the safety risks associated with the use of n-butanol in industrial processes. [ABSTRACT FROM AUTHOR]

Fossil fuel extraction and utilization are associated with several environmental issues. This study examined how altering the blending proportions of mixed diesel/biodiesel/n-butanol fuels impacts combustion. Additionally, it delved into the functioning of diesel engines when utilizing these blended fuels as well as conventional diesel. A three-dimensional fluid dynamics simulation was constructed and corroborated against test outcomes obtained at 25%, 50%, 75%, and 100% loads. The findings indicated that the n-butanol addition enhanced the indicated thermal efficiency. At a 100% load, D70B30 (70% diesel + 30% biodiesel), D70B25BU5 (70% diesel + 25% biodiesel + 5%N-butanol), D70B20BU10, and D70B10BU20 exhibited 4.76%, 5.75%, 6.79%, and 8.71% higher indicated thermal efficiency values than D100 (100% diesel), respectively. The introduction of butanol enhanced the combustion environment within the combustion chamber. Compared with pure diesel, all blended fuels reduced hydrocarbon and carbon monoxide emissions across various loads. The blended fuels showed significant reductions in hydrocarbon emissions of 1%, 4%, 6%, and 15% compared with that of diesel under the 25% load, respectively. [ABSTRACT FROM AUTHOR]

In this study, the physicochemical properties of canola and waste cooking oil biodiesels, as well as various binary biodiesel blends, were investigated according to TS EN 14214 and ASTM D 6751 standards. Critical parameters such as density, kinematic viscosity, cold filter plugging point (CFPP), calorific value, flash point, copper strip corrosion, water content, and ester yield were evaluated. The findings highlighted the notable density of C100 and W100 biodiesels, with the addition of butanol reducing density. While viscosity values adhered to standards, the addition of butanol was observed to decrease viscosity. CFPP values indicated compliance with standards only for C100 and C75W25. Flash points of C100 and W100 biodiesels met standards, but the addition of butanol to binary biodiesel blends lowered flash points. Copper strip corrosion values were determined to comply with standards for all fuels. Calorific values demonstrated the prominence of C100 and W100 biodiesels, with the addition of butanol observed to decrease calorific values in binary biodiesels. While water content favored canola biodiesel over waste cooking oil biodiesel, the addition of butanol to binary biodiesels increased water content. Regarding ester yield, C100 biodiesel exhibited the highest yield, and the addition of butanol to binary biodiesels increased ester yield. In conclusion, this study thoroughly analyzed the physicochemical properties of biodiesel and blend fuels, revealing the impact of butanol addition on these properties.

The esterification reaction of n‐butanol and acetic acid has been performed in batch reactor in the presence of different homogeneous acid catalyst, namely sulfuric acid, nitric acid, and para toluene sulfonic acid (p‐TSA). The objective of present research work is to investigate kinetic behavior of esterification reaction over the temperature range of 60°C–80°C. The effect of reaction parameter such as catalyst loading varied from 1% to 5% v/v and acid to alcohol molar ratio of 1:1, 1:3, and 1:5 has been observed. A pseudo homogeneous kinetic model has been applied. Kinetic parameters such as equilibrium constant, reaction rate constant, enthalpy, activation energy, and entropy were calculated by the experimental data for different acid catalyst system. It was observed that sulfuric acid gives higher conversion 73% than p‐TSA 68.5% and nitric acid 66.25% at temperature of 80°C, 1:1 molar ratio and 3% catalyst concentration. The activation energy was estimated 36448.49, 23324.31 and 19060.156 J/mol K for three different catalyst sulfuric acid, nitric acid and p‐TSA respectively. The enthalpy and entropy of the esterification reaction of acetic acid with n‐butanol over three different catalysts has been calculated (Enthalpy: 25.788 KJ/mol, 12.256 KJ/mol, 28.320 KJ/mol, Entropy: 88.1 J/mol K, 45.298 J/mol K, 91.44 J/mol K) and found enthalpy is having positive value that shows reaction is endothermic. [ABSTRACT FROM AUTHOR]

Almost all small organics, in theory, could be potential feedstock for production of hydrogen via steam reforming (SR). Nevertheless, not all organics contain a linear carbon chain like ethanol or acetone. How do ring structure of an organic substrate impacted coking behaviors in SR were explored herein with n-butanol and tetrahydrofuran (THF) as the research objects over Ni/SiO 2 catalyst, due to the same carbon number but distinct carbon chains in these two molecules. The results indicated that furan ring in THF lowered reactivity towards SR, as its adsorption on metallic sites was more difficult than n-butanol. The in-situ IR analysis for measuring reaction intermediates suggested that n-butanol and THF involved generation of intermediates with C O formed via dehydrogenation, C x H y formed via cracking and C C species that can be further gasified or aggregate to coke. However, more oxygenated intermediates generated in SR of n-butanol than in THF, rendering n-butanol more reactive towards SR. This, however, also formed substantially more coke of aliphatic nature in amorphous form, which led to the coke of thermally unstable and had higher tendency being oxidized. In converse, coke formed from SR of THF was more aromatic, showing less impact on catalytic activity, higher thermal stability, and larger crystal size with more carbon nanotube form of coke. This was closely connected with the ring structures that could dehydrogenated to form the unsaturated ring with capability to involve in Diels-Alder reactions, forming coke of aromatic nature. [Display omitted] • The short-term stability reforming activity of THF remained unchanged, while the activity of n-butanol decreased. • The coke formed by steam reforming of THF has the superior antioxidant properties and the higher thermal stability. • More oxygenated intermediates formed (e.g. C O) in steam reforming of n-butanol than that in THF. • In the steam reforming process of THF, the coke formed to the catalyst surface is more aromatic. • Coke on THF steam reforming is much less and is mainly catalytic type with high crystallinity. [ABSTRACT FROM AUTHOR]

The pursuit of ecologically friendly and sustainable energy solutions is currently at the forefront of scientific study and technological advancements. The replacement of fossil fuels is a serious challenge in diesel engines. Furthermore, several researchers are concerned about lower-rate hydrogen enrichment and NOx emissions. In the current study, 50 mg/l of graphene nanoplatelets (G) and 10% of n-Butanol are used as additives in sterculia foetida biodiesel-diesel blends, along with H 2 supply (at a flow rate of 3 and 6 lpm) as a secondary fuel, to improve the overall performance and reduce emissions of a single-cylinder, four-stroke, compression ignition engine. The combination of 20% biodiesel is blended in 80% diesel (B20), 50 mg/l of G included B20 (B20G50), 10 vol % of n-Butanol (on a volume basis) added in B20G50 blend (B20G50+n-Bu10) are used as piloted fuel. Besides, hydrogen enriched with air as a secondary fuel and B20G50+n-Bu10 fuel blend supplied as piloted fuel (B20G50+n-Bu10+3H 2 , and B20G50+n-Bu10%+6H 2) are fueled to determine the performance, combustion, and emission characteristics of a CI engine. The addition of G and n-butanol in a B20 blend with a higher flow rate of H 2 enrichment improved performance (Brake thermal efficiency increased by 7.54%, and Brake specific fuel consumption decreased by 20.75%). In contrast, the combustion parameters such as cylinder pressure and Heat release rate are improved by 9.8 and 6.23% at 100% load for the same blend. In contrast, emission characteristics of Carbon monoxide, Hydrocarbons, and smoke opacity are lowered by 19.75, 24.86, 9.58, and 8.8%, respectively, at higher loads as compared to the B20 blend. The higher heating value, improved atomization characteristics, superior flame velocity of H 2 , greater thermal diffusivity, the catalytic effect of nanoplatelets, and higher oxygen level of n-butanol improved engine performance, combustion, and decreased emission characteristics on diesel engines with no engine modifications. The outcomes of this research may be beneficial to run stationary engines used in various industrial sectors. • BTE increased by 7.54% for B20G50+n-Bu10 piloted fuel and 6 lpm of H 2 compared to B20 blend. • CO, HC, and smoke opacity decreased by 19.75, 24.86, and 8.8% for B20G50+n-Bu10+6H 2. • CP and HRR increased by 9.8, and 6.23% for G and n-Butanol dispersed B20 with H 2 enrichment. • NOx is reduced by 9.58% for B20G50+n-Bu10 sample. [ABSTRACT FROM AUTHOR]

The goal of this study is to see how greater the exhaust gas recirculation (EGR) and quaternary blend approach affect the performance, emission, and combustion parameters of a Common Rail Direct Injection (CRDI) engine with various quaternary blends. In this study, we will use bio-fuels in replacement of diesel by 30–40% that emits less oxides of nitrogen (NOx) and soot. In light of this, combustion, exhaust emissions, and performance parameters of 1-cylinder CRDI engine powered by quaternary blends (QB) of diesel, vegetable oil, biodiesel, and 1-butanol by volume% were explored experimentally. To determine the effect on engine characteristics, with no EGR, 6% EGR and 12% were evaluated with various blends and base fuels. At peak load with 12% EGR, the experimental examination revealed a 2-percent decline in brake thermal efficiency (BTE), a small rise of 3.8% in brake-specific fuel consumption (BSFC) among blends in performance. In emissions, 12% EGR rate reported best results, i.e. average of 54% NOx reduction among blends, 14% rise in hydrocarbon (HC) and carbon monoxide (CO) at full load. The maximum NOx reduction has been reported by QB3 blend at 12% EGR rate and at full load is 54%. EGR rate of 12% was helpful in decreasing NOx emissions in a greater extend while little sacrificing in HC and CO. [ABSTRACT FROM AUTHOR]

N-butanol, a standard volatile organic compound (VOC) gas with toxicity and flammability, seriously endangers human life and health. It is imperative to achieve rapid and trace detection of n-butanol. Oxygen vacancies have been proven to be an essential factor for VOC gas adsorption at the surface of metal oxide semiconductor (MOS) gas sensors. In view of the above, BiFeO3 (BFO) nanoparticles with abundant oxygen vacancies were prepared via simple sol–gel and annealing. Crystal structure, morphology, and compositions were systematically analyzed by a series of characterizations (XRD, SEM, HRTEM, EPR, and XPS). The response of the synthesized BFO-2 sensor reached 19.37 to 100 ppm n-butanol with a detection limit of 0.28 ppm at an optimal operating temperature of 280 °C. In addition, BFO-2 also has a fast response time, good stability and repeatability, and favorable selectivity to n-butanol. It is crucial to systematically explore the excellent selectivity of BFO sensors due to their abundant oxygen vacancies and large intrinsic crystal defects. Herein, adjusting the calcination temperature is one constructive strategy to tune the oxygen vacancy, which would prompt the gas sensing performance of BFO sensors to n-butanol. [ABSTRACT FROM AUTHOR]

Herein, a novel Co3O4/ZnO heterostructured composite was successfully fabricated using a facile one-pot method in combination with subsequent heat treatment, which showed excellent performance in detecting n-butanol. The crystal structure, micromorphology, pore structure, molecular structure, and surface elemental valence structure of the composite were subjected to systematic characterization including XRD, TEM, SEM, BET, and XPS techniques. It was demonstrated that Co3O4/ZnO composite mainly existed in the form of mesoporous pores with an average pore size of 46.64 nm. While applied in gas sensing experiments, all sensors tended to increase at 280 °C and then decreased as the temperature continued to rise. Furthermore, at each working temperature, the response values of Co3O4/ZnO sensors outweighed that of pure ZnO sensors, with Co3O4/ZnO-2 sensor (108) six times greater than pure ZnO (18). The response recovery time also exhibited a 25 s and 10 s improvement, respectively. Eventually, the behind gas sensitivity mechanism of Co3O4/ZnO sensor was explored and the formation of heterojunctions and bigger pore sizes in composites was proved to be key contributors to the improved gas sensitivity. [ABSTRACT FROM AUTHOR]

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Oxygen oxidation of the styrene epoxide (SE)–p-toluene sulfonic acid (TSA) double system (DS) in solutions of three primary alcohols, 1-octanol (OCT), n-butanol (BUT), and ethanol (ET), is studied. The corresponding concentration expressions of oxidation rates are as follows: VOCT = k [SE]0 [TSA]1, VBUT = k [SE]0 [TSA]0.63, and VET = k [SE]0 [TSA]0.7 at [SE] [TSA]. The proximity of the oxidation activation energies in three alcohols contrasts with the difference in the oxidation rates: the oxidation rate in ET is three times the rate in n-butanol and thirty times the oxidation rate in 1-octanol. [ABSTRACT FROM AUTHOR]

The efficient detection of n-butanol, which is in demand for highly sensitive materials, is essential for multiple applications. A nonaqueous method was applied to prepare NiFe2O4 nanoparticles (NPs) using benzyl alcohol as a solvent, which shows a size of 7.9 ± 1.6 nm and a large surface area of 82.23 m2/g. To further improve the sensing performance for n-butanol, Pd/PdO functionalization was sensitized with NiFe2O4 NPs. Gas sensing results demonstrate that the Pd/PdO-NiFe2O4 exhibits an enhanced response of 36.9 to 300 ppm n-butanol and a fast response and recovery time (18.2/17.6 s) at 260 °C. Furthermore, the Pd/PdO-NiFe2O4-based sensor possesses a good linear relationship between responses and the n-butanol concentration from 1 to 1000 ppm, and great selectivity against other volatile organic compounds (VOCs). The excellent sensing enhancement is attributed to the catalytic effects of Pd/PdO, the increase of oxygen vacancies, and the formation of heterojunction between PdO and NiFe2O4. Thus, this study offers an effective route for the synthesis of Pd/PdO-functionalized NiFe2O4 NPs to achieve n-butanol detection with excellent sensing performance.

This paper describes studies on the preparation of an o–cresol–furfural–formaldehyde resin in the presence of an alkaline catalyst and its modification with n-butanol or 2-ethylhexanol. The novelty of this research is to obtain a furfural-based resin of the resole type and its etherification. Such resins are not described in the literature and also are not available on the market. The obtained resin based on furfural, which can be obtained from agricultural waste, had a low minimum content of free o–cresol < 1 wt.%, furfural < 0.1 wt.%, and formaldehyde < 0.1 wt.%. The resin structure was characterized by mass spectrometry (ESI-MS), FT-IR, and NMR spectroscopy, which showed the presence of hydroxymethylene groups in the resin before modification and alkyl groups derived from n-butanol and 2-ethylhexanol after modification. The etherified resins had a lower viscosity and were more flexible (DSC) than the resin before modification and they can be used as an environmentally friendly, safe, and sustainable alternative to traditional phenol–formaldehyde resins in the paint industry. They demonstrate the ability to create a protective coating with good adherence to metal substrates and an excellent balance of flexibility and hardness.

Biodiesel has emerged as a viable renewable fuel with the potential to reduce reliance on fossil fuels and partially replace petroleum-based fuels. Moreover, using biodiesel reduces pollutant emissions. However, utilizing biodiesel results in inferior engine performance along with elevated NOx emissions. There is a scope to address these concerns by employing n-butanol and metallic nanoparticles (NPs) as fuel additives. In this study, castor oil biodiesel is blended with 100 ppm Ni and Al NPs and diesel along with n-butanol forming various stable fuel blends such as D100, D90B10, D80B10Bu10, D90B10+Ni, D80B10Bu10+Ni, D90B10+Al, and D80B10Bu10+Al to investigate their effect on engine performance and emission. The use of n-butanol substantially diminishes engine performance. However, the inclusion of Ni and Al NPs with D90B10 increases torque by 2.33% and 2.04%, increases BP by 2.33% and 2.04%, decreases BFSC by 8.96% and 6.13%, and increases BTE by 8.87% and 5.43%, respectively. Moreover, the addition of Ni and Al NPs to D80B10Bu10 increases torque by 14.99% and 8.09%, increases BP by 14.99% and 8.09%, decreases BFSC by 5.06% and 7.68%, and increases BTE by 3.81% and 6.49%, respectively. The use of n-butanol with a biodiesel blend drastically lowers CO and NOx emissions. The inclusion of Ni and Al nanoadditive further reduces CO and NOx emissions. The addition of Ni and Al NPs to D90B10 decreases CO emission by 12.07% and 14.66% and decreases NOx emission by 4.27% and 9.82%, respectively. In addition, the inclusion of Ni and Al NPs with D80B10Bu10 decreases CO emission by 16.43% and 13.15% and decreases NOx emission by 3.98% and 10.75%, respectively.

The primary motivation of this paper is to report the effects of n-butanol addition (5, 20 and 35% by volume) to diesel fuel on regulated and polycyclic aromatic hydrocarbon (PAH) emissions of a diesel engine. PAH samples were quantified using rigorous analytical chemistry procedures to determine total PAHs, PAH dispersion and PAH toxicity. In comparison with diesel fuel, all n-butanol blends (DBu5, DBu20, and DBu35) reduced nitrogen oxides (NOx) emissions by 6.77%, 9.59%, and 20.08% and total PAH emissions by 66.86%, 75.33%, and 80.98%. In terms of the relative distribution of PAHs, a significant decrease was recorded in higher cyclic PAHs such as Pyrene, Benzo[a]anthracene, Chrysene, Benzo[k]floranthene, Benzo[a]pyrene for all blends. Similarly, the amount of the toxicity of the PAH emissions also decreased by 11.66%, 87.53%, and 67.28% with DBu5, DBu20 and DBu35 blends, respectively. With the addition of n-butanol to the diesel fuel, total PAH emissions were detected below the Occupational Safety and Health Administration's (OSHA)-Permissible Exposure Level. Overall, it was demonstrated that n-butanol addition to diesel fuel significantly reduced PAH formation which is helpful to prevent wet stacking, and prolong the operating time of the diesel engine especially at low loads or cold operating conditions. [ABSTRACT FROM AUTHOR]

The article presents the results of research on the impact of feeding marine reciprocating internal combustion engines with blends of diesel fuel and n-butanol on their performance parameters. The study includes a research plan and empirical results, in which the engine efficiency and emissions of harmful compounds in the exhaust gases were determined. A promising aspect is also the decrease in the concentration of NOx, which has a positive impact on reducing the toxicity of exhaust gases. An important aspect of the passive defence of a vessel is the reduction of exhaust gas temperature under nominal loads. [ABSTRACT FROM AUTHOR]

At present, there are still few gas sensors for detecting n‐butanol at room temperature. It is worth noting that detecting target gas at room temperature is beneficial to reduce energy consumption and prolong the lifetime of sensors. In this work, different molar ratios Au nanoparticles modified SnO2 derived from Sn‐MOF hollow cubes (Au‐SnO2) are synthesized by the coprecipitation method. The Au‐SnO2 has higher specific surface area than pure SnO2, which is conducive to improving gas sensing. The 0.7% Au‐SnO2 exhibit excellent sensing performances of 240% toward 100 ppm n‐butanol and the actual detection interval is 200 ppb–500 ppm under the room temperature. Meanwhile, DFT calculations reveal that Au‐SnO2 gas sensor has wonderful selectivity to n‐butanol at room temperature. The enhancement of n‐butanol sensing performance is also related to the "catalytic sensitization" effect and the "electron sensitization" effect triggered driven by Au NPs. It is hoped this Au‐SnO2 sensing material with such great gas response, selectivity and low detection limit will help detect n‐butanol at room temperature to lower energy consumption. [ABSTRACT FROM AUTHOR]

Butanol has good combustion properties and it can be a viable alternative fuel for automotive spark ignition engines due to its ability to improve energy and pollution performance. This paper analyses the influence of butanol content in gasoline blends on engine operation with a focus on operation stability, thermal efficiency and emissions. A Cielo Nubira A15MF engine type with four cylinders and a 1.5 L displacement was turbocharged and it was fueled with butanol in a blend with gasoline in percent's of 10% vol. and 15% vol. An operation regime of 2500 1/min speed and 55% engine load was used, at different dosages, at which the engine power remained constant. Regarding the engine fueled with butanol in a blend with gasoline, the operation stability was improved, especially when lean dosages were used; the dosages at which the thermal efficiency was higher are comparative to classic fueling. Concerning the use of lean dosages, the combustion duration decreases and the energetic engine performance was improved when butanol was used comparative to gasoline. When butanol was used, polluting emissions and emission with a greenhouse effect were reduced. The sharp reduction in NOx is highlighted in this paper. [ABSTRACT FROM AUTHOR]

The present study utilizes dual biodiesel-alcohol blends to evaluate the engine performance. Five test fuels were prepared on a volume basis with different constituting percentages, each consisting of 70 % pure diesel (D70), a binary blend of biodiesel: B1 (WCO30), a ternary blend of biodiesel: B2 (WCO15 and WCCO15) and three quaternary blends: B3 (WCO10, WCCO15, Bu5), B4 (WCO15, WCCO10, Bu5) and B5 (WCO10, WCCO10, Bu10). The biodiesel is made from used cooking oil. The effects of each blend on engine performance were examined by performing the engine test on a single-cylinder, four-stroke, water-cooled Kirloskar compression ignition (CI) engine at various engine speeds and loads. The indicated power (IP), brake power (BP), friction power (FP), fuel consumption (FC), and mechanical efficiency (%) were evaluated, and the experimental results show that the performance is best for B3 when run with 75 % of the maximum load capacity of the engine. The study thus justifies that to lower the density and viscosity of biodiesel fuel, adding alcohol can be acknowledged as a valuable application to boost the engine's brake thermal efficiency (BTE). This also lowers the emissions of oxides of nitrogen (NOx), carbon monoxide (CO), and hydrocarbons (HC). [ABSTRACT FROM AUTHOR]

Abstract Background Osteochondral defects pose an enormous challenge without satisfactory repair strategy to date. In particular, the lateral integration of neo-cartilage into the surrounding native cartilage is a difficult and inadequately addressed problem determining tissue repair’s success. Methods Regenerated silk fibroin (RSF) based on small aperture scaffolds was prepared with n-butanol innovatively. Then, the rabbit knee chondrocytes and bone mesenchymal stem cells (BMSCs) were cultured on RSF scaffolds, and after induction of chondrogenic differentiation, cell-scaffold complexes strengthened by a 14 wt% RSF solution were prepared for in vivo experiments. Results A porous scaffold and an RSF sealant exhibiting biocompatibility and excellent adhesive properties are developed and confirmed to promote chondrocyte migration and differentiation. Thus, osteochondral repair and superior horizontal integration are achieved in vivo with this composite. Conclusions Overall, the new approach of marginal sealing around the RSF scaffolds exhibits preeminent repair results, confirming the ability of this novel graft to facilitate simultaneous regeneration of cartilage–subchondral bone.

Abstract Under high ambient pressure (5 MPa) and different injection pressures (90, 120, and 150 MPa), a high‐speed imaging technique was carried out to comparatively investigate the macroscopic spray characteristics of diesel with three different types of blended fuel in a constant volume chamber. The oxygenated fuels were n‐butanol (B), pine oil (P), and 2,5‐dimethylfuran (DMF). All their blending ratio with diesel were 20%. Results showed that less viscosity could be improved the spray characteristics of the fuel in the range of experimental conditions. Then, the tested fuels had a longer penetration and a greater spray area with increasing the injection pressure from 90 to 150 MPa. On the other hand, the percentage increases in the mean spray cone angle of D100, B20, P20, and DMF20 were 3%, 4.4%, 2.4%, and 2.9%, respectively. At the same experimental condition, the spray penetrations of DMF20 and P20 were larger than that of D100, but the spray penetration of B20 was basically similar to D100. Besides, the performance of the spray cone angle and spray area were D100

SnO 2 is a typical metal oxide semiconductor gas sensitive material, which has been studied deeply. However, pure SnO 2 sensing materials usually have good performance at high operating temperatures. In this study, we reported an n-butanol sensor with high selectivity and fast response based on SnO 2 submicron porous cube prepared by heating and decomposing the Sn-based metal-organic framework material (Sn-MOF) in air at a certain temperature. SnO 2 submicron porous cube prepared at 450 °C shows good response and selectivity for n-butanol. And it has a response (%) of 175% to 100 ppm n-butanol and a relatively fast response/recovery time of 184 s/183 s at room temperature. The (110) crystal plane with sufficient oxygen-rich vacancy can adsorb O 2 and n-butanol molecules more effectively. Therefore, its sensitivity to n-butanol gas can be significantly improved. This work provides a good idea for further research on pure metal oxide semiconductor room temperature gas sensors. [ABSTRACT FROM AUTHOR]

The pericarp of the Longkong fruit rapidly browns during ambient storage, typically reducing its shelf life to between 3 and 7 days. Recently, n-butanol has demonstrated a promising effect in preventing this deterioration, extending the shelf life of tropical fruits to more than a week. The present study exploited this opportunity to examine the exogenous application of aqueous n-butanol at various concentrations (0.2–0.6%) in controlling pericarp browning and suppressing different oxidoreductase enzymes in the pericarp under prolonged ambient storage conditions (8 days). Every two days, the fruit pericarps were tested for color (lightness (L*), redness (a*), and yellowness (b*)), browning index (BI), membrane permeability loss (MPL), malondialdehyde (MDA) content, total phenolic content (TPC), and reactive oxygen species (ROS). Enzymes including phenylalanine ammonia lyase (PAL), polyphenol oxidase (PPO), phospholipase D (PLD), lipoxygenase (LOX), superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPX) were also analyzed. All sample test results showed that increased storage significantly impacted color characteristics (decreased L*, b* and increased a*, and BI). MPL, MDA, and ROS also continuously increased. Furthermore, the browning-related enzymes (PAL and PPO), membrane-degrading enzymes (PLD and LOX), and antioxidant enzymes (SOD, CAT, and GPX) continuously increased in all pericarp samples throughout the storage. Among the samples, pericarp color, BI, MPL, MDA, PAL, PPO, PLD, and LOX were significantly high in the control samples, consequently adversely affecting the quality and shelf life of Longkong. On the other hand, the n-butanol-treated samples significantly controlled the loss and all problematic enzymes while improving the activities of SOD, CAT, and GPX in the pericarp. Furthermore, the positive effect of n-butanol application was dose-dependent; higher concentrations (0.4–0.6%) performed well in protecting the fruit from deterioration. [ABSTRACT FROM AUTHOR]

The dual direct injection strategy can flexibly control the reactivity distributions and equivalence ratio, which shows a great potential in realizing clean and efficient combustion. However, the sprays' collision is inevitable when the fuel sprays are injected into the combustion chamber simultaneously owing to limited in-cylinder space, which is rarely investigated. The investigation aims to explore the atomization and combustion characteristics of collision between biodiesel and butanol sprays at different injection delay times of biodiesel (0, 0.5, 1, 1.5, 2 ms). Experiments are conducted in a constant volume combustion chamber. The collision spray and combustion images are captured by optical diagnosis techniques. Several macroscopic parameters are obtained, including spray behavior, spray area, ignition delay, ignition location, flame behavior, flame lift-off length, and natural luminosity intensity. Results show that the variation of injection delay time can effectively change the spray distribution and realize the concentration stratification. The liquid-phase diffusion region increases with an increased premixed charge of butanol spray, but the total evaporation time has a tiny difference. The sprays' collision can promote the ignition process, but the ignition location is slightly affected by the injection delay time of biodiesel. A trade-off relationship between the vapor-phase diffusion area and combustion characteristics is found. When the injection delay time exceeds 0.5 ms, a longer injection delay time can lead to a larger vapor-phase area, which causes smaller equivalent ratio, longer flame-off length, and lower luminosity intensity. However, a longer injection delay would lead to an uncomplete combustion of the n-butanol spray. At the experimental cases, the injection delay time of biodiesel should be 1/2–2/3 injection duration to realize complete combustion and small emissions. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the antioxidant and antibacterial capacity of crude extract and bioactive compounds from the aerial parts of Helianthemum lippii. The antioxidant activities of the crude extract and fractions (dichloromethane, ethyl acetate, n-butanol, and anthocyanins) were assayed by Diphenyl 2-pycril hydrazine (DPPH), reducing power (RP), Total Antioxidant Capacity (TAC) and linoleic acid/ß - carotene bleaching assay. Their antibacterial activity against six bacterial strains was evaluated by Agar diffusion and a modified broth macro-dilution method was used to measure the minimum inhibitory concentration (MIC). Its phenolic content was also verified by quantitative estimations. The results demonstrated this plant and its fractions have an excellent capacity antioxidant, as dichloromethane fraction exhibited the highest antioxidant activity in tested DPPH, RP assays, and TAC with IC50 and effective concentration (EC50) values of 2.404 µg/mL, 0.592 µg/mL, 1.58 mg Ascorbic acid/g of extract respectively. In addition, dichloromethane fraction showed promising antibacterial activity, with strong efficiency against six strains bacteria with the inhibition zone reaching even 26.67 mm, while the MIC was very similar in all fractions and much better than the crude extract so that it ranged in values from 0.1563 to 0.9375 mg/mL. Finally, it is worth noting this plant and its fractions is a promising source of medicinal uses that could be applied in the treatment of many diseases caused by oxidative stress and bacterial infection. [ABSTRACT FROM AUTHOR]

The kinetics of butyl lactate production by the interaction of ammonium lactate with n-butanol in the presence of water in the temperature range of 130–170°C in a closed system was studied for the first time as one of the stages of a new integrated technology for the production of lactic acid and polylactide. Also for the first time, a reaction scheme and kinetic model of ammonium lactate esterification with n-butanol were proposed, taking into account the side formation of lactamide and the acid catalysis of esterification by lactic acid. The developed kinetic model can be used for mathematical modeling of a reactor for the synthesis of butyl lactate. [ABSTRACT FROM AUTHOR]

Among oxygenated alternative fuels, n-butanol is considered as a promising alternative biofuel which can partially (or fully) replace conventional transportation fuels currently in use. However, before n-butanol can be commercially utilised, its fundamental combustion characteristics need to be fully understood. In this work, the effect of adding n-butanol on autoignition property of iso-octane was studied. Measurements of ignition delay times for the two blends of n-butanol proportions of 30% and 50% by mole weight were made in a Rapid Compression Machine for stoichiometric mixtures at 2.0 MPa and temperature range 651-918 K. n-butanol increased ignition delay times of iso-octane at lower temperatures and hence acted as an octane enhancer, while at higher temperatures delay times were reduced. In the intermediate temperatures there was visually no difference in delay times between the two blends. Throughout the temperature range studied, the delay times of both blends were much closer to those of pure n-butanol which suggests that the combustion chemistry of n-butanol was dominant over that of iso-octane. These results have shown that n-butanol can enhance fuel octane rating and therefore can potentially improve thermal efficiency of SI engines, whilst CI engines can benefit from the reduced delay times at higher temperatures. [ABSTRACT FROM AUTHOR]