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This study investigated the effects of using ferric oxide nanoparticles (FO) and C2–C4 alcohols with diesel/biodiesel blend in a diesel engine. Optimum operating conditions were explored, and an engine speed of 1750 rpm was optimal. The concentration of FO was estimated to be 760 ppm, considering the best conditions for carbon nanotube (CNT) production. Ethanol was immiscible in diesel fuel; however, any biodiesel percentage in the blend made it miscible. The used engine was too small to run with a blend containing more than 3 % ethanol. Propanol and butanol were blended at the same ethanol concentration for comparative purposes. A blend with 30 % biodiesel (B30) was found to be the best diesel/biodiesel blend. This was detected by the best coefficient of variation (COV) with reasonable performance and emissions. Ferric oxide nanoparticles reduced COV and improved engine performance. The COV increased for tested alcohols. However, blending B30 with alcohols, especially butanol, improved thermal efficiency. FO and alcohol increased NOx emissions and decreased both CO and smoke opacity. They increased the peak pressure and the heat release rate while reducing the combustion duration. Nonetheless, no CNT traces were detected in the present study under any conditions. [ABSTRACT FROM AUTHOR]

Hydrophobic ionizable organic compounds (HIOCs) like per‐ and polyfluoroalkyl substances (PFAS), pharmaceuticals, and surfactants have been detected in water supplies. Anion exchange is an effective process for the removal of HIOCs from water. Regeneration solution comprising methanol (ca. 75% v/v) and brine is used to effectively desorb HIOCs from resins to overcome the combination of electrostatic and non‐electrostatic interactions. This research investigated different mono‐ and polyhydroxy alcohol cosolvents with brine to regenerate resins saturated with HIOCs to understand the effects of cosolvent properties on regeneration. For PFAS desorption using 25% v/v alcohol in 5% NaCl solution, regeneration efficiency increased in the order methanol < ethanol < 1‐propanol. Experiments with the pharmaceutical diclofenac and surfactant dodecylbenzene sulfonate showed similar regeneration efficiency using 75% v/v methanol in 5% NaCl solution and 25% v/v 1‐propanol in 5% NaCl solution and higher regeneration efficiency using 1‐propanol than ethanol or methanol at the same volume fraction. [ABSTRACT FROM AUTHOR]

This study investigated the effects of using ferric oxide nanoparticles (FO) and C2–C4 alcohols with diesel/biodiesel blend in a diesel engine. Optimum operating conditions were explored, and an engine speed of 1750 rpm was optimal. The concentration of FO was estimated to be 760 ppm, considering the best conditions for carbon nanotube (CNT) production. Ethanol was immiscible in diesel fuel; however, any biodiesel percentage in the blend made it miscible. The used engine was too small to run with a blend containing more than 3 % ethanol. Propanol and butanol were blended at the same ethanol concentration for comparative purposes. A blend with 30 % biodiesel (B30) was found to be the best diesel/biodiesel blend. This was detected by the best coefficient of variation (COV) with reasonable performance and emissions. Ferric oxide nanoparticles reduced COV and improved engine performance. The COV increased for tested alcohols. However, blending B30 with alcohols, especially butanol, improved thermal efficiency. FO and alcohol increased NOx emissions and decreased both CO and smoke opacity. They increased the peak pressure and the heat release rate while reducing the combustion duration. Nonetheless, no CNT traces were detected in the present study under any conditions.

IntroductionThe influence of chitosan's physicochemical characteristics on the functionality of lactic acid bacteria and the production of lactic acid remains very obscure and contradictory to date. While some studies have shown a stimulatory effect of oligochitosans on the growth of Lactobacillus spp, other studies declare a bactericidal effect of chitosan. The lack and contradiction of knowledge prompted us to study the effect of chitosan on the growth and productivity of L. bulgaricus in the presence of chitosan and its derivatives.MethodsWe used high molecular weight chitosan (350 kDa) and oligochitosans (25.4 and 45.3 kDa). The experiment was carried out with commercial strain of L. bulgaricus and the low fat skim cow milk powder reconstituted with sterile distilled water. After fermentation, dynamic viscosity, titratable acidity, pH, content of lactic acid, colony forming units, chitosan and oligochitosans radii were measured in the samples. Fermented dairy products were also examined using sodium dodecyl sulfate electrophoretic analysis, gas chromatography-mass spectrometry and light microscopy.Results and discussionThe results of the study showed that when L. bulgaricus was cultured in the presence of 25.4 kDa oligochitosans at concentrations of 0.0025%, 0.005%, 0.0075% and 0.01%, the average rate of LA synthesis over 24 hours was 11.0 × 10−3 mol/L/h, 8.7 × 10−3 mol/L/h, 6.8 × 10−3 mol/L/h, 5.8 × 10−3 mol/L/h, respectively. The 45.3 kDa oligochitosans had a similar effect, while the average rate of lactic acid synthesis in the control sample was only 3.5 × 10−3 mol/L/h. Notably, 350 kDa chitosan did not affect the rate of lactic acid synthesis compared with the control sample. Interestingly, interaction of chitosan with L. bulgaricus led to a slowdown in the synthesis of propanol, an increase in the content of unsaturated and saturated fatty acids, and a change in the composition and content of other secondary metabolites. The quantity of L. bulgaricus in a sample with 0.01% chitosan exceeded their content in the control sample by more than 1,700 times. At the same chitosan concentration, the fermentation process was slowed down, increasing the shelf life of the fermented milk product from 5 to 17 days while maintaining a high content of L. bulgaricus (6.34 × 106 CFU/g).

The aim of this study was to develop and characterize CuO/Cu2O functionalized with AgPt nanostructures for gas sensing applications. Environmental pollution remains a pressing global concern, requiring effective detection methods. Metal oxide nanostructures, such as those based on copper oxides, offer promising solutions due to their sensitivity and selectivity for various gases. The research investigated the morphology and structure of the nanostructures using techniques such as scanning electron microscopy (SEM), X-ray diffraction (XRD), and Raman spectroscopy. In addition, the nanostructures were functionalized with noble metals such as silver and platinum to enhance their sensory properties. The deposition of polymer layers has been investigated as a method to improve sensor selectivity. The gas sensing properties of the CuO/Cu2O/AgPt nanostructures were evaluated using the Keithley 2400 source meter and showed high sensitivity to gases such as propanol, acetone, hydrogen, and ammonia at elevated temperatures. The results showed that higher operating temperatures result in faster response and recovery times. In addition, the nanostructures exhibited saturation in response at higher concentrations of certain gases. These results highlighted the potential of CuO/Cu2O/AgPt nanostructures in environmental monitoring applications, particularly in industries prone to gas emissions. Overall, this research contributes to the advancement of gas sensing technology for pollution prevention and control efforts.

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Pure nanocrystalline SnO2 powders calcined at three different temperatures of 400, 600 and 800°C have been successfully synthesized by chemical co-precipitation method with the starting material SnCl2·2H2O and 2-propanol as a precursor. The crystallite sizes of 10, 12 and 15 nm were obtained for three different temperatures, respectively, and the rutile tetragonal structure was confirmed by XRD pattern. SEM micrographs of all the samples were found to be particulate agglomerated and further crystallite size increases as the temperature increases. The peaks of EDAX reveal that the prepared sample constitutes purely tin and oxide atoms. UV–visible spectra show that the bandgap energy values were 3.05, 3.36 and 3.20 eV. Photoluminescence studies exhibit relative intensity of 422 nm, a small broad peak and somewhat intense peak at 440 nm for the samples annealed at 400, 600 and 800°C. The specific capacitance values of the prepared samples were found to be 380, 335, 548 F g–1 for the samples annealed at 400, 600 and 800°C from cyclic voltammetric studies. Galvanostatic charge–discharge analysis predicts the faradic redox reaction from its symmetric curves. [ABSTRACT FROM AUTHOR]

In this study, an artificial neural network (ANN) was used to estimated the performance and exhaust emission parameters of a diesel engine running on diesel, biodiesel, and propanol fuel mixtures. In addition, the parameters estimated by ANN were tried determining the optimum operating parameter by using Response Surface Methodology (RSM). In the experimental study, propanol was added in 3 different ratios (5%, 10% and 20%) into 100% diesel, 80% diesel and 20% biodiesel fuel blends. In addition, engine tests, were made at 5 different engine speeds with 400 min-1 intervals between 1000 min-1 and 2600 min-1 revolutions at full load. In addition, HC (Hydrocarbon), CO (Carbon Monoxide), NOX (Nitrogen oxides) and Smoke emissions were measured during in the working. ANN model was developed for estimation of engine output parameters depending on fuel mixture ratios and engine speed. In the ANN results, the regression coefficients (R2) of the proposed model were found to be between 0.924 and 0.99. When the obtained ANN results were compared with the experimental results, it was seen that the maximum mean relative error (MRE) was 6.895%. It has been shown that the applied model can predict with a low error rate. The RSM results showed that the optimum operating parameters were 2034-min-1 engine speed, 74.667% diesel, 11.36% biodiesel and 15% propanol fuel mixture. In addition, in the validation tests of the model where the desirability was 0.7833%, the highest error rate was obtained as 7.37% as a result of NOX. As a result of the study, it was seen that RSM supported ANN is a good method for estimating diesel engine parameters working with diesel/biodiesel/propanol mixtures and determining optimum operating parameters. [ABSTRACT FROM AUTHOR]

Solution plasma is a gas-phase discharge in the vapor bubbles in a solution and has the potential to efficiently produce H2 by decomposing aqueous alcohols. However, the mechanism of alcohol decomposition in solution plasma remains unclear. In this study, lower monohydric alcohols (methanol and ethanol, as well as 1- and 2-propanol) were treated in solution plasma, and in this paper, the gasification mechanism is discussed. The gases produced from these alcohols were mainly H2 and CO, with small ratios of C1–C3 hydrocarbons. Thus, the O/C ratio in the product gas was close to 1 for all alcohols, and most of the C atoms in the alcohols were bonded to O atoms. This excess of O atoms could have only come from water, suggesting a strong contribution of OH radicals from water for gasification. However, the C1–C3 hydrocarbons were produced solely by the decomposition of the alcohol. For both decomposition routes, possible reaction pathways are proposed that are consistent with the experimental facts such as the composition of the product gas and the intermediates detected.

The interaction of the methyl orange (MO) dye with cetyltrimethylammonium bromide (CTAB) in propanol, butanol, and water was studied using spectrophotometry method. The NLREG approach was used to compute the distribution constant which is the lower as carbon number increases which resembles that value of distribution constant 0.07161476, 0.00060913, 0.00010865 is of water, 1-propanol, 1-butanol media respectively. The Benesi-Hilderbrand and Hashemi and Sun equations were also used to determine the binding constant (Kb) and Gibbs free energy of binding (ΔG°). As the alkyl chain lengthened, the ΔG° value shifted more negatively in comparison to water. The spontaneous nature of CTAB binding with MO was suggested by the negative value of ΔG°. As the concentration of CTAB in the water & alcoholic media increased, the MO absorption dramatically blue-shifted from 464 nm (water) to 440–450 nm (propanol, butanol). These findings showed that the alkyl chain plays a role in reducing absorbance. The MO absorbance in the water, 1-propanol or 1-butanol media decreased with increasing CTAB concentration (hyperchromic shift).

Polypropylene synthesis is a critical process in the plastics industry, where control of catalytic activity is essential to ensure the quality and performance of the final product. In this study, the effect of two inhibitors, propanol and arsine, on the properties of synthesized polypropylene was investigated. Experiments were conducted using a conventional catalyst to polymerize propylene, and different concentrations of propanol and arsine were incorporated into the process. The results revealed that the addition of propanol led to a significant decrease in the Melt Flow Index (MFI) of the resulting polypropylene. The reduction in the MFI was most notable at a concentration of 62.33 ppm propanol, suggesting that propanol acts as an effective inhibitor by slowing down the polymerization rate and thus reducing the fluidity of the molten polypropylene. On the other hand, introducing arsine as an inhibitor increased the MFI of polypropylene. The maximum increase in the MFI was observed at a concentration of 0.035 ppm arsine. This suggests that small amounts of arsine affect the MFI and Mw of the produced PP. Regarding the catalyst productivity, it was found that as the concentration of propanol in the sample increased (approximately seven ppm), there was a decrease in productivity from 45 TM/kg to 44 TM/kg. Starting from 10 ppm, productivity continued to decline, reaching its lowest point at 52 ppm, with only 35 MT/kg. In the case of arsine, changes in catalyst productivity were observed at lower concentrations than with propanol. Starting from about 0.006 ppm, productivity decreased, reaching 39 MT/kg at a concentration of 0.024 ppm and further decreasing to 36 TM/kg with 0.0036 ppm. Computational analysis supported the experimental findings, indicating that arsine adsorbs more stably to the catalyst with an energy of −60.8 Kcal/mol, compared to propanol (−46.17 Kcal/mol) and isobutyl (−33.13 Kcal/mol). Analyses of HOMO and LUMO orbitals, as well as reactivity descriptors, such as electronegativity, chemical potential, and nucleophilicity, shed light on the potential interactions and chemical reactions involving inhibitors. Generated maps of molecular electrostatic potential (MEP) illustrated the charge distribution within the studied molecules, further contributing to the understanding of their reactivity. The computational results supported the experimental findings and provided additional information on the molecular interactions between the inhibitors and the catalyst, shedding light on the possible modes of inhibition. Solubles in xylene values indicate that both propanol and arsine affect the polymer's morphology, which may have significant implications for its properties and final applications. [ABSTRACT FROM AUTHOR]

In this work, TiO2 nanowires (TNWs) were synthesized using a plasma‐assisted method, and then Pt clusters were impregnated onto these TNWs. The nanowires supported Pt when combined with various tungsten‐based co‐catalysts, which improved the catalytic performance. The direct conversion of cellulose to C2‐C3 alcohols using tungsten‐based co‐catalysts was enhanced, even at low temperatures. X‐ray photoelectron spectroscopy (XPS) and Raman analysis showed oxygen vacancy (Ov) enrichment on the surface of Pt/TiO2 in the presence of tungsten co‐catalysts, which improved their catalytic activity. The role of metallic platinum (Pto) was also investigated and was found to have a linear relationship with their activity as follows: H2WO4 > (NH4)6H2W12O40 · xH2O > H3PW12O40. Maximum yields of 32.33% and 51.52% of ethanol and propane‐2‐ol at optimum temperatures of 220 and 250 °C, respectively, were obtained with H2WO4. A catalytic reaction performed using tandem catalytic system gave a high ethanol yield of 25.56%, which is low in comparison with an integrated catalytic system. Cellulose conversion was also quantified here by probe electrospray ionization (pESI) coupled with Fourier transform mass spectroscopy (FTMS), which was never reported earlier for these reactions. This method provides evidence of negligible fragmentation of high molecular‐weight compounds, and the maximum cellulose conversion reported here is 100%. A reaction pathway is proposed, based on the experimental results, which elaborates the activation and cleavage of specific C‐C and C‐O bonds. © 2023 Society of Industrial Chemistry and John Wiley & Sons Ltd. [ABSTRACT FROM AUTHOR]

Alcohol compounds have become a popular choice as additives for improving the performance of biodiesel. However, given the complexity of biodiesel, which is composed of various components of vegetable oil, it requires intensive research to fully understand its behavior. This study aims to investigate the impact of alcohol compounds on the droplet combustion characteristics of linoleic acid, an unsaturated fatty acid. Four alcohol compounds, namely methanol, ethanol, propanol, and butanol, were utilized to evaluate their effects on the combustion properties of the fuel mixtures. The droplet combustion characteristics were observed under normal atmospheric pressure and temperature conditions, with the fuel mixture consisting of 80 % linoleic acid and 20 % alcohol compounds. Our findings indicate that the addition of alcohol compounds to linoleic acid significantly reduced the ignition delay time, although the droplet lifetime was slightly increased. Moreover, it was observed that alcohols with shorter carbon chains had a greater impact on reducing the ignition delay time. Additionally, the results demonstrated that the alcohol compounds could accelerate the rate of increasing combustion temperature, reduce soot formation, and shorten the duration of soot formation. Furthermore, it was found that alcohol with a short carbon chain had a more pronounced effect on the overall combustion characteristics of linoleic acid. Overall, our study sheds light on the effects of alcohol compounds on the droplet combustion characteristics of linoleic acid, providing valuable insights for the optimization of biodiesel performance. [ABSTRACT FROM AUTHOR]

In this work, the micellization behavior of tetradecyltrimethylammonium bromide ‎‎(TTAB) surfactant was investigated in aqueous solvent mixtures of methanol, ethanol ‎and propanol on different mass fractions (10-30%) and aqueous solution of Ponceau 4R ‎and Sunset yellow FCF dyes at concentrations (0.001-0.007mM) based on ‎conductometric technique at T=(298-313)K. The critical micelle concentration (CMC) ‎values and dissociation degrees of TTAB surfactant were determined. The obtained ‎results showed that the CMC value increases with rising of methanol and ethanol mas ‎fractions but the CMC value decreases with rising of propanol mas fractions. Also, the ‎obtained results indicated that the CMC value decreases with concentration increasing of ‎Ponceau 4R and Sunset yellow FCF dyes. In addition, thermodynamic properties such as ‎the Gibbs energy, enthalpy and entropy of micellization were calculated as a function of ‎temperature, dye concentration and alcohol mass fractions. ‎

Solution plasma is a gas-phase discharge in the vapor bubbles in a solution and has the potential to efficiently produce H2 by decomposing aqueous alcohols. However, the mechanism of alcohol decomposition in solution plasma remains unclear. In this study, lower monohydric alcohols (methanol and ethanol, as well as 1- and 2-propanol) were treated in solution plasma, and in this paper, the gasification mechanism is discussed. The gases produced from these alcohols were mainly H2 and CO, with small ratios of C1–C3 hydrocarbons. Thus, the O/C ratio in the product gas was close to 1 for all alcohols, and most of the C atoms in the alcohols were bonded to O atoms. This excess of O atoms could have only come from water, suggesting a strong contribution of OH radicals from water for gasification. However, the C1–C3 hydrocarbons were produced solely by the decomposition of the alcohol. For both decomposition routes, possible reaction pathways are proposed that are consistent with the experimental facts such as the composition of the product gas and the intermediates detected. [ABSTRACT FROM AUTHOR]

Although alcohols are toxic to many microorganisms, they are good carbon and energy sources for some bacteria, including many pseudomonads. However, most studies that have examined chemosensory responses to alcohols have reported that alcohols are sensed as repellents, which is consistent with their toxic properties. In this study, we examined the chemotaxis of Pseudomonas putida strain F1 to n-alcohols with chain lengths of 1 to 12 carbons. P. putida F1 was attracted to all n-alcohols that served as growth substrates (C2 to C12) for the strain, and the responses were induced when cells were grown in the presence of alcohols. By assaying mutant strains lacking single or multiple methyl-accepting chemotaxis proteins, the receptor mediating the response to C2 to C12 alcohols was identified as McfP, the ortholog of the P. putida strain KT2440 receptor for C2 and C3 carboxylic acids. Besides being a requirement for the response to n-alcohols, McfP was required for the response of P. putida F1 to pyruvate, l-lactate, acetate, and propionate, which are detected by the KT2440 receptor, and the medium- and long-chain carboxylic acids hexanoic acid and dodecanoic acid. β-Galactosidase assays of P. putida F1 carrying an mcfP-lacZ transcriptional fusion showed that the mcfP gene is not induced in response to alcohols. Together, our results are consistent with the idea that the carboxylic acids generated from the oxidation of alcohols are the actual attractants sensed by McfP in P. putida F1, rather than the alcohols themselves.IMPORTANCE Alcohols, released as fermentation products and produced as intermediates in the catabolism of many organic compounds, including hydrocarbons and fatty acids, are common components of the microbial food web in soil and sediments. Although they serve as good carbon and energy sources for many soil bacteria, alcohols have primarily been reported to be repellents rather than attractants for motile bacteria. Little is known about how alcohols are sensed by microbes in the environment. We report here that catabolizable n-alcohols with linear chains of up to 12 carbons serve as attractants for the soil bacterium Pseudomonas putida, and rather than being detected directly, alcohols appear to be catabolized to acetate, which is then sensed by a specific cell-surface chemoreceptor protein.

The quaternary blends (diesel–biodiesel-vegetable oil-alcohol) offer enormous potential for reducing fossil fuel usage and mitigating air pollution caused by marine diesel engines. Biodiesel and alcohol are alternate fuels possessing high oxygen content, ensuring clean combustion. Vegetable oil is beneficial in saving diesel contribution and increasing engine lubrication. The objective of the present work was to reduce the dependency on conventional diesel and to come up with cleaner fuel that can also improve engine performance. This experimental work aims to lower exhaust emissions by fueling a single-cylinder, four-stroke direct-injection diesel engine with novel quaternary blends comprising diesel (50%), sunflower biodiesel (25%), sunflower oil (5%), and alcohol (20%). In order to develop cleaner fuel than diesel, different quaternary blends were prepared by varying the length of the carbon chain of alcohols in the blends, namely, DBOEth20, DBOProp20, DBOBut20, DBOHep20, and DBODec20. The performance emissions of quaternary blends were tested at varied engine loads from 5 to 20 Nm (full load), while engine speed was fixed at 1800 rpm. The results indicate that DBOProp20 resulted in the lowest fuel consumption and highest thermal efficiency. DBOProp20 reduced CO2, NOx, and smoke emissions by 19.6%, 9.9%, and 85.7%, as compared to diesel. However, DBODec20 succeed in mitigating CO emission by 41.37% at 100% load. DBOBut20 proved to be most promising in reducing UHC emission by a maximum of 71.69% at 100% load. The highest BTE of 10.98% with lowest BSFC of 13.04% was recorded for DBOProp20 at 100% engine load, in comparison to pure diesel. [ABSTRACT FROM AUTHOR]

The effects of propanol and 1, 3-propanediol on fatty acid and biomass accumulation in Schizochytrium ATCC 20888 were explored. Propanol increased the contents of saturated fatty acids and total fatty acids by 55.4 and15.3%, while 1, 3-propanediol elevated the polyunsaturated fatty acids, total fatty acids and biomass contents by 30.7, 17.0, and 6.89%. Although both of them quench ROS to increase fatty acids biosynthesis, the mechanisms are different. The effect of propanol did not reflect on metabolic level while 1, 3-propanediol elevated osmoregulators contents and activated triacylglycerol biosynthetic pathway. The triacylglycerol content and the ratio of polyunsaturated fatty acids to saturated fatty acids were significantly increased by 2.53-fold, which explained the higher PUFA accumulation in Schizochytrium after adding 1, 3- propanediol. At last, the combination of propanol and 1, 3-propanediol further elevated total fatty acids by approximately 1.2-fold without compromising cell growth. These findings are valuable for scale-up production of designed Schizochytrium oil for various application purposes. [ABSTRACT FROM AUTHOR]

Experimental binary diffusion coefficients for short-chain alcohols in supercritical carbon dioxide were measured using the Taylor dispersion technique in a temperature range of 306.15 K to 331.15 K and along the 10.5 MPa isobar. The obtained diffusion coefficients were in the order of 10−8 m2 s−1. The dependence of D on temperature and solvent density was examined together with the influence of molecular size. Some classic correlation models based on the hydrodynamic and free volume theory were used to estimate the diffusion coefficients in supercritical carbon dioxide. Predicted values were generally overestimated in comparison with experimental ones and correlations were shown to be valid only in high-density regions. [ABSTRACT FROM AUTHOR]

Recently, reactivity controlled compression ignition (RCCI) has been proposed in order to achieve a higher thermal efficiency with lower emissions than conventional combustion. In RCCI mode, as the fuel types and their combinations affects the reactivity stratification inside cylinder, thus combustion control, in present study, iso-propanol was evaluated as low-reactivity fuel (LRF) when petroleum diesel, commercial biodiesel and their blends were high-reactivity fuels. It is of great importance that iso-propanol and biodiesel be used together in RCCI mode, as they significantly affect the in-cylinder stratification due to their high octane/cetane number. Therefore, the reactivity controlled compression ignition (RCCI) combustion characteristics was investigated in a diesel research engine using iso-propanol, petroleum diesel, biodiesel and their blends as fuels. Tests were conducted on varying loadings (from 20% to 60% of max torque) and premixed ratios of LRF (Rp = 0, 0.15, 0.30, 0.45, and 0.60) at a constant engine speed of 2400 rpm. Results, which were compared with conventional diesel combustion (CDC), showed that, as the premixed ratio (Rp) of low-reactivity fuel (iso-propanol) increased, ignition delay (ID) period prolonged while combustion duration (CD) and rate of pressure rise (RoPR) reduced assisted to reduce NO emissions and smoke opacity in the exhaust. NO and smoke opacity reduced simultaneously for biodiesel-propanol combinations up to 40% under 20% load and 0.60 premixed ratio of LRF compared to CDC. Propanol premixed ratio of 0.30 at 60% load was found to be optimum concerning lowest emissions. In conventional mode, HC emissions reduced by up to 52% when biodiesel and its blends with diesel fuel are used, whereas they increased significantly in RCCI mode. According to overall results, it is concluded that RCCI performed better than CDC at entire load.

Conformational analysis of the experimentally recorded IR absorption spectra of propanol in gaseous state and in a low-temperature argon matrix at 20 K and at 35 K was carried out for different spectral ranges. It showed that the conformational composition of the samples in gas and in matrix isolation is different. In gaseous propanol Gt conformers predominate, while in matrix isolation the most energetically favorable form is Tg conformer, which prevails in percentage at both considered temperatures of an Ar matrix. [ABSTRACT FROM AUTHOR]

Most research studies have focused on reducing NOx emitted from diesel engines by adding oxygenated fuels (such as alcohol and biodiesel) to diesel to prepare a good alternative to conventional diesel fuels. Biofuels produced from vegetable oil and waste cooking oil while alcohol can be produced from sugarcane and corn. In the current study, the biodiesel used in the tests was derived from waste cooking oil. In this study, the influence of adding Exhaust Gas Recirculation (EGR) to diesel, biodiesel (D80B20), diesel-pentanol (D85PEN15), diesel octanol (D90OCT10), diesel-propanol (D95PRO5) and diesel-biodiesel-pentanol (D50B40PEN10) blends on performance and emitted pollutants of a diesel engine was investigated. The practical experiments were divided into two parts, the first section comparing the results of using diesel and other fuels at different speeds 2100, 2400, 2700 and 3000 rpm at constant loads without EGR. The second section studied the effect of adding EGR in variable proportions (5 %, 10 %, 15 % and 20 %) to the studied fuel mixtures at constant loads and speed. The results showed that adding biodiesel to diesel (without EGR) increases brake specific fuel consumption, NOx and CO2 emissions by 13.66 %, 41.35 % and 30.49 %, respectively, but, the thermal efficiency of the brakes, exhaust gas temperatures, UHC and CO decreases at rates of 12.58 %, 10.22 %, 18.9 % and 21.31 %, respectively, compared to diesel. When EGR was added at 20 %, the maximum increase for D80B20, D95PRO5, ED100, and D85PENT15 was: 18.38 %, 24.60 %, 45.84 %, and 20 %, respectively, compared to when no EGR was added. The thermal efficiency, exhaust gases temperature and NOx levels decreased when EGR rate was raised. [ABSTRACT FROM AUTHOR]

Selective hydrogenolysis of glycerol to propanol is a sustainable reaction, which can play a critical role in the future of the propylene market, as one step dehydration of this sustainable propanol provides access to sustainable propylene. In this work, Copper (Cu) – Tungstosilicic acid (HSiW) catalysts were studied for the hydrogenolysis of glycerol. For the first time over a Cu catalyst, this study reports a yield of ∼76 % for direct conversion of glycerol to propanols in continuous flow mode. Several advanced characterization techniques were employed to study the fresh and used catalysts. The presence of intact Keggin units of HSiW solid acid (with medium acidity) in the vicinity of small clusters of copper sites improved the performance and lifetime of these bifunctional catalysts. This study offers insights into the nature of the active sites required for the hydrogenolysis reaction, which was achieved without using expensive PGMs. [ABSTRACT FROM AUTHOR]

Polypropylene synthesis is a critical process in the plastics industry, where control of catalytic activity is essential to ensure the quality and performance of the final product. In this study, the effect of two inhibitors, propanol and arsine, on the properties of synthesized polypropylene was investigated. Experiments were conducted using a conventional catalyst to polymerize propylene, and different concentrations of propanol and arsine were incorporated into the process. The results revealed that the addition of propanol led to a significant decrease in the Melt Flow Index (MFI) of the resulting polypropylene. The reduction in the MFI was most notable at a concentration of 62.33 ppm propanol, suggesting that propanol acts as an effective inhibitor by slowing down the polymerization rate and thus reducing the fluidity of the molten polypropylene. On the other hand, introducing arsine as an inhibitor increased the MFI of polypropylene. The maximum increase in the MFI was observed at a concentration of 0.035 ppm arsine. This suggests that small amounts of arsine affect the MFI and Mw of the produced PP. Regarding the catalyst productivity, it was found that as the concentration of propanol in the sample increased (approximately seven ppm), there was a decrease in productivity from 45 TM/kg to 44 TM/kg. Starting from 10 ppm, productivity continued to decline, reaching its lowest point at 52 ppm, with only 35 MT/kg. In the case of arsine, changes in catalyst productivity were observed at lower concentrations than with propanol. Starting from about 0.006 ppm, productivity decreased, reaching 39 MT/kg at a concentration of 0.024 ppm and further decreasing to 36 TM/kg with 0.0036 ppm. Computational analysis supported the experimental findings, indicating that arsine adsorbs more stably to the catalyst with an energy of −60.8 Kcal/mol, compared to propanol (−46.17 Kcal/mol) and isobutyl (−33.13 Kcal/mol). Analyses of HOMO and LUMO orbitals, as well as reactivity descriptors, such as electronegativity, chemical potential, and nucleophilicity, shed light on the potential interactions and chemical reactions involving inhibitors. Generated maps of molecular electrostatic potential (MEP) illustrated the charge distribution within the studied molecules, further contributing to the understanding of their reactivity. The computational results supported the experimental findings and provided additional information on the molecular interactions between the inhibitors and the catalyst, shedding light on the possible modes of inhibition. Solubles in xylene values indicate that both propanol and arsine affect the polymer’s morphology, which may have significant implications for its properties and final applications.

A novel methanogenic strain, CaP3V-MF-L2AT, was isolated from an exploratory oil well from Cahuita National Park, Costa Rica. The cells were irregular cocci, 0.8–1.8 μm in diameter, stained Gram-negative and were motile. The strain utilized H2/CO2, formate and the primary and secondary alcohols 1-propanol and 2-propanol for methanogenesis, but not acetate, methanol, ethanol, 1-butanol or 2-butanol. Acetate was required as carbon source. The novel isolate grew at 25–40 °C, pH 6.0–7.5 and 0–2.5% (w/v) NaCl. 16S rRNA gene sequence analysis revealed that the strain is affiliated to the genus Methanofollis. It shows 98.8% sequence similarity to its closest relative Methanofollis ethanolicus. The G + C content is 60.1 mol%. Based on the data presented here type strain CaP3V-MF-L2AT (= DSM 113321T = JCM 39176T) represents a novel species, Methanofollis propanolicus sp. nov. [ABSTRACT FROM AUTHOR]

Alcoholic fuels have recently come to light as a sustainable source for powering today's vehicles. Various studies have investigated the effects of alcoholic fuels on engine efficiency and emission characteristics. However, scarce literature is available for their effects on lubricant. Therefore, propanol-gasoline fuel mixtures, with concentrations of 9% (P9) and 18% (P18) propanol, were made to compare their engine characteristics and lubricating oil condition with that of pure gasoline (0 percent propanol (P0)). To determine the rate of deterioration, the characteristics of the lubricating oil were evaluated after 100 h of engine operation, as suggested by the manufacturer. When compared with unused lube oil, P18 showed reductions in flash point temperature and kinematic viscosity of 14% and 36%, respectively, at 100 °C. For P18, which contains Fe (27 PPM), Al (11 PPM), and Cu (14 PPM), the highest wear element concentrations in the lubricating oil were found. The moisture in the degraded oil was well within the allowable limit for the three fuel mixtures. With the increase in propanol percentage in the propanol-gasoline blend, the engine performance was increased. Compared to P9 and P0, P18 had the partially unburned emissions. [ABSTRACT FROM AUTHOR]

Detection of lung cancer biomarkers (LCBs) from exhaled breath in the early stage can lower lung cancer mortality. We report a highly sensitive dealuminated zeolite Y (DaY)/SnO2 nanoparticle (NP)-based sensor for the detection of LCBs at low concentrations. The sensing performances were tested with 200 ppb propanol, formaldehyde, and toluene LCBs at different operating temperatures from 175 to 300 °C. The sensor was found to be highly efficient for propanol detection with a remarkable relative response of ∼96 ± 2% and a fast response time of ∼10 ± 1 s at 275 °C. The sensor stability was evaluated with multiple loading–deloading cycles with concentrations ranging from 70 to 200 ppb propanol. The DaY/SnO2 NP sensor was stable for multiple detection cycles of LCBs and exhibited a high relative response at 225 °C for concentrations as low as 70 ppb propanol. The activation energy was calculated for all LCBs, and the lowest was measured for propanol at 56.7 kJ/mol. The DaY zeolite plays the role of an excellent catalyst in the dehydration of propanol molecules into propene. A sensing mechanism was also proposed for the DaY/SnO2 NP sensor based on the catalytic behavior of the zeolite DaY as well as the role of the activation energy of LCBs on the SnO2 NP surface. [ABSTRACT FROM AUTHOR]

Biodiesel has established itself as a renewable fuel that is used in transportation worldwide and is partially or in some cases completely replacing conventional fuels. Chemically, biodiesel is a fatty acid monoalkyl ester (FAAE). Generally, the term biodiesel refers to the fatty acid methyl or ethyl esters (FAME or FAEE). Herein, an overview of the research on the synthesis of FAAE in which the alkyl moiety is a C3+ alkyl chain (branched/unbranched) is given. In addition, a comparison of the properties of the aforementioned FAAE with each other, with FAME and FAEE, and with fuel standards is given. The length of the alkyl chain has a major influence on viscosity, while pour point temperatures are generally lower when branched alcohols are used, but the fatty acid part of the molecule also has a major influence. The development of new pathways for the synthesis of higher alcohols from biomass opens a future perspective for the production of long chain FAAE as biofuels, fuel additives, or biolubricants. Due to their properties, FAAEs produced from C3–C5 alcohols have the potential to be used as fuels, while all C3+ FAAEs can be used as valuable bioadditives, and C8+ FAAEs can be used as biolubricants and viscosity improvers. [ABSTRACT FROM AUTHOR]

Studies on alternative and renewable fuels are maintaining due to the ever-decreasing of petroleum usage and also the environmental pollution that it has created. Alternative fuels, especially renewable fuels are one of the most emphasized issues because renewable energy sources are environmentally friendly, unconsumable and easily degradable in the environment. In this study, biodiesel was obtained from safflower. The biodiesel of safflower oil was mixed with propanol at different ratios and tested as a diesel engine fuel. The effects of both biodiesel and propanol addition on engine performance, combustion parameters and pollutant exhaust emissions have been experimentally tested. The main important point of the presented study is to detect the effects of higher ratios of pure diesel fuel in diesel engines by utilizing the positive sides of a light alcohol, the propanol. The engine performance, specific fuel consumption and emission values of the biodiesel and propanol blended fuels did not show a significant difference compared to the diesel. In the loaded cases, the combustion parameters for all test fuels were obtained in a similar manner. Peak values of HRR in higher engine loads of blend fuels with high propanol were a bit higher. It is seen that there is a decrease in NOx emissions. Safflower biodiesel and propanol mixtures can be used as alternative fuels by adding to diesel fuel in certain amounts.

The search for alternative fuels that can limit the use of traditional fossil fuels to power internal combustion engines is one of the main tasks faced by both the modern automotive industry and the modern energy industry. This paper presents experimental tests of a compression ignition engine, in which the conventional fuel, i.e., diesel, was partially replaced with propyl alcohol, i.e., a renewable biofuel. Studies on the co-combustion of diesel fuel with propanol were carried out, in which the energy share of alcohol varied from 0 to 65%. The research showed that an increase in the proportion of propanol, up to 30%, resulted in a significant increase in the rate of heat release and the rate of pressure increase in the cylinder of a compression-ignition engine. Increasing the alcohol content to 65% resulted in an increase in the ignition delay time and significantly shortened the duration of combustion. During the combustion of diesel fuel with a 50% propanol share, the engine was characterized by maximum efficiency, higher than diesel fuel combustion by 5.5%. The addition of propanol caused a slight deterioration of the combustion stability determined by the coefficient of variation for IMEP. The study of engine exhaust emissions has shown that the combustion of diesel fuel with a small proportion of propanol, up to 30%, causes an increase in nitrogen oxide emissions, while up to 50% contributes to a decrease in HC emissions. The increased share of alcohol contributed to a significant decrease in the emissions of both carbon monoxide and carbon dioxide, and caused a significant reduction in the concentration of soot in the exhaust of the compression-ignition engine. [ABSTRACT FROM AUTHOR]

Alcohol-derived biofuels are used as an alternative fuel source instead of petroleum-based fuels. There is a need to understand the fire behavior of these blended alcohol biofuels. Twelve laboratory-scale pool fire experimental tests were conducted at quiescent ambient air on n-propanol, diesel, and mixtures to understand the burning characteristics, like burning rate, flame temperature, and flame height. The burning rate of pure and blended fuels was estimated by two methods and compared. Visual images of fire were analyzed, and it was found that the maximum visible flame height of all fuels is nearly three-times the pool diameter. Centerline flame temperature is highest for n-propanol pool fires compared with diesel and its blends. A dimensionless temperature parameter φ makes a linear relationship with dimensionless vertical height for pure and binary mixtures. These combustion characteristics of blended fuel pool fire help ensure the safety of blended fuel handling, transportation, and storage. [ABSTRACT FROM AUTHOR]

Ethanol, n -propanol, isopropanol, n -butanol, isobutanol, and sec-butanol are six potential carbon-neutral fuels of the future. One application of these carbon-neutral fuels is in high-dilution spark ignition. To understand the potential of these fuels in high-dilution spark ignition, this work experimentally determines the spark ignition lean flammability limit of each fuel with no external, cooled exhaust gas recirculation (EGR), and with 20% external, EGR. The spark ignition lean flammability limit in this work is defined as the excess-air ratio that results in a coefficient of variance of gross indicated mean effective pressure greater than 5%. This is done on an engine with a compression ratio of 12.5, using an intake pressure of 1 bar and an intake temperature of 320 K. It was found that ethanol had the leanest lean limit, due to its high flame speed, followed by n -propanol, isopropanol, and sec-butanol, which all had similar lean limits. n -Butanol and isobutanol had the richest lean limits due their high knock propensity and low flame speed, respectively. The lean limit of each fuel decreased with external, cooled EGR addition, with ethanol as the least sensitive and isopropanol as the most sensitive to EGR addition. Overall, using a high dilution strategy increased the cycle efficiency for each fuel. Ethanol, n -propanol, isopropanol, and sec-butanol all showed promising performance and are great candidates to be combined with an advanced high-dilution SI strategy to enable high-dilution SI with a carbon-neutral fuel. [ABSTRACT FROM AUTHOR]

Diazepam (DZP) is a benzodiazepine drug used as an anti-drug and sedative. It is often misused to induce or create euphoria in combination with other drugs (high or fly sensation) or administered alone. So far, screening for DZP abuse with sensitive analytical methods is needed, as its small concentrations make it difficult to detect. Increased sensitivity of the analytical method can be obtained by using a preparation method that selectively separates the analyte from the sample matrix. Molecularly imprinted polymer (MIP) is one of the preparation solutions with good selectivity, specificity, and sensitivity. MIP was made from DZP as a template, itaconic acid, and ethylene glycol dimethacrylate in a composition of 1:4:20. MIP was made by precipitation polymerisation to obtain microsphere polymer type. MIP had a binding capacity value of 0.0557 mg/g and followed the Freundlich isotherm. Application of the microsphere MIP on spiked blood serum resulted in a recovery of 105.63 ± 1.0% for MIP compared to 21.28 ± 0.4% for non-imprinted polymer, with the imprinting factor value reaching 4.96. Hence, MIP DZP with itaconic acid as a functional monomer and propanol as a porogen, fabricated by the precipitation polymerisation method, is a promising sorbent for DZP extraction in biological fluids.

Experimental binary diffusion coefficients for short-chain alcohols in supercritical carbon dioxide were measured using the Taylor dispersion technique in a temperature range of 306.15 K to 331.15 K and along the 10.5 MPa isobar. The obtained diffusion coefficients were in the order of 10−8 m2 s−1. The dependence of D on temperature and solvent density was examined together with the influence of molecular size. Some classic correlation models based on the hydrodynamic and free volume theory were used to estimate the diffusion coefficients in supercritical carbon dioxide. Predicted values were generally overestimated in comparison with experimental ones and correlations were shown to be valid only in high-density regions.

Recovery of energy from waste is appealing as it meets the energy demand and minimize the problems associated with waste management. Biodiesel derived from waste cooking oil was used in this study along with 1-propanol and 1-hexanol to make a comparative assessment of the alcohol addition on different diesel engine characteristics. Experimental trials were carried out by utilizing two ternary blends with 20% by volume of higher alcohols (propanol & hexanol), 30% by volume of biodiesel and 50% by volume of diesel. Later, the results were compared with binary blend of 50% by volume of diesel and 50% by volume of biodiesel (D50B50), pure diesel (D100) and biodiesel (B100). Results divulge that ignition delay period got longer for both Pr20 blend and HX20 blend which resulted in a 2% and 1% increase in peak cylinder pressure and 26% and 15% increase in peak heat release rate respectively against D50B50 blend operation. In comparison with the binary blend, the engine brake thermal efficiency improved by 3% and deteriorated by 2% against hexanol and propanol blend respectively. The NOx emission aggravated with ternary blends, nearly 8% higher NOx emission was observed for propanol blend when compared to hexanol blend. Both smoke opacity and carbon monoxide emission reduced, while unburnt hydrocarbon emission was on the higher side with the introduction of alcohol. It is concluded from the observations that the HX20 blend was found to be optimal in terms of improved engine performance and emission characteristics. [ABSTRACT FROM AUTHOR]

Converting plant biomass into biofuels and biochemicals via microbial fermentation has received considerable attention in the quest for finding renewable energies and materials. Most approaches have so far relied on cultivating a single microbial strain, tailored for a specific purpose. However, this contrasts to how nature works, where microbial communities rather than single species perform all tasks. In artificial coculture systems, metabolic synergies are rationally designed by carefully selecting and simultaneously growing different microbes, taking advantage of the broader metabolic space offered by the use of multiple organisms. 1-propanol and 2-propanol, as biofuels and precursors for propylene, are interesting target molecules to valorize plant biomass. Some solventogenic Clostridia can naturally produce 2-propanol in the so-called Isopropanol-Butanol-Ethanol (IBE) fermentation, by coupling 2-propanol synthesis to acetate and butyrate reduction into ethanol and 1-butanol. In this work, we hypothesized propanoate would be converted into 1-propanol by the IBE metabolism, while driving at the same time 2-propanol synthesis. We first verified this hypothesis and chose two propionic acid bacteria (PAB) strains as propanoate producers. While consecutive PAB and IBE fermentations only resulted in low propanol titers, coculturing Propionibacterium freudenreichii and Clostridium beijerinckii at various inoculation ratios yieldedmuch higher solvent concentrations, with asmuch as 21 g/l of solvents (58% increase compared to C. beijerinckii monoculture) and 12 g/l of propanol (98% increase). Taken together, our results underline how artificial cocultures can be used to foster metabolic synergies, increasing fermentative performances and orienting the carbon flow towards a desired product. [ABSTRACT FROM AUTHOR]

Density functional theory (DFT) method was carried out to investigate the molecular interaction between metalloporphyrin-based sensor and propanol. The relative energies were used to determine the most stable state of metalloporphyrin and its complexes at three different spin states for further theoretical studies. The low-spin states were found to be the most stable states for cobalt porphyrin (CoP), tin porphyrin (Sn), and zinc porphyrin (ZnP) before exposure to propanol and CoP, SnP, ZnP, iron porphyrin (FeP), ruthenium porphyrin (RuP) after exposure to propanol. The intermediate-spin state was found to be the most stable states for the other metalloporphyrins and their complexes, except for manganese porphyrin (MnP) after exposure to propanol. The calculated binding energies were shown the following order for metalloporphyrin-based sensor-binding propanol: MnP>ZnP>CoP>RuP>SnP>FeP>AgP>CuP. This calculated result may be useful for the theoretical design of metalloporphyrin-based sensor for propanol determination and perhaps other analyte. [ABSTRACT FROM AUTHOR]

Kaposiform hemangioendothelioma (KHE) represents a rare, borderline vascular tumor with locally aggressive behavior. They are often associated with a potentially life-threatening coagulopathy known as Kasabach–Merritt phenomenon (KMP). Due to heterogeneous nature of the vascular lesion and lack of standardized treatment protocols, these patients pose a diagnostic dilemma and therapeutic challenge with morbidity and potential mortality. We report successful management of an infant with KHE and associated KMP. Difficulties encountered in diagnosis, initiation of therapy, and role of dual therapy with vincristine and steroids are discussed.

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Alcoholic fuels have recently come to light as a sustainable source for powering today’s vehicles. Various studies have investigated the effects of alcoholic fuels on engine efficiency and emission characteristics. However, scarce literature is available for their effects on lubricant. Therefore, propanol-gasoline fuel mixtures, with concentrations of 9% (P9) and 18% (P18) propanol, were made to compare their engine characteristics and lubricating oil condition with that of pure gasoline (0 percent propanol (P0)). To determine the rate of deterioration, the characteristics of the lubricating oil were evaluated after 100 h of engine operation, as suggested by the manufacturer. When compared with unused lube oil, P18 showed reductions in flash point temperature and kinematic viscosity of 14% and 36%, respectively, at 100 °C. For P18, which contains Fe (27 PPM), Al (11 PPM), and Cu (14 PPM), the highest wear element concentrations in the lubricating oil were found. The moisture in the degraded oil was well within the allowable limit for the three fuel mixtures. With the increase in propanol percentage in the propanol-gasoline blend, the engine performance was increased. Compared to P9 and P0, P18 had the partially unburned emissions.

Biodiesel has established itself as a renewable fuel that is used in transportation worldwide and is partially or in some cases completely replacing conventional fuels. Chemically, biodiesel is a fatty acid monoalkyl ester (FAAE). Generally, the term biodiesel refers to the fatty acid methyl or ethyl esters (FAME or FAEE). Herein, an overview of the research on the synthesis of FAAE in which the alkyl moiety is a C3+ alkyl chain (branched/unbranched) is given. In addition, a comparison of the properties of the aforementioned FAAE with each other, with FAME and FAEE, and with fuel standards is given. The length of the alkyl chain has a major influence on viscosity, while pour point temperatures are generally lower when branched alcohols are used, but the fatty acid part of the molecule also has a major influence. The development of new pathways for the synthesis of higher alcohols from biomass opens a future perspective for the production of long chain FAAE as biofuels, fuel additives, or biolubricants. Due to their properties, FAAEs produced from C3–C5 alcohols have the potential to be used as fuels, while all C3+ FAAEs can be used as valuable bioadditives, and C8+ FAAEs can be used as biolubricants and viscosity improvers.

[Display omitted] • Propanol exhibits higher dehydrogenation barriers than isopropanol for NODH. • Dehydrogenation of ketone requires higher activation energy than that of aldehyde. • Isopropanol shows higher selectivity than propanol towards the carbonyl product. • Propanol shows the least barrier towards esterification in the reaction scheme. Density functional theory (DFT) simulations are conducted to understand the differentiation of activity and selectivity trends between primary and secondary alcohols towards the non-oxidative dehydrogenation (NODH) reaction. Propanol and isopropanol are employed as model molecules to explore the NODH on the (111) facets of Cu. The initial dehydrogenation of propanol via the hydroxyl route exhibits a higher barrier (96.8 kJ/mol) as compared to that of isopropanol (61.4 kJ/mol). Furthermore, the second dehydrogenation step resulting in the formation of the carbonyl compound is also calculated to show higher barrier of primary alcohol (83 kJ/mol) than secondary alcohol (51.3 kJ/mol). Overall, for the consecutive dehydrogenation steps, propanol is observed to show higher activation barriers as opposed to that of isopropanol, indicating towards a higher conversion rate for isopropanol, similar to the trend observed experimentally. However, the subsequent dehydrogenation of the carbonyl compound formed shows a barrier of 112.8 kJ/mol for acetone and that of 70.6 kJ/mol for acetaldehyde owing to the higher stability of ketone. The formation of ester from the propionyl produced upon acetaldehyde dehydrogenation is calculated to show the lowest barrier (64.6 kJ/mol) amongst the dehydrogenation steps of primary alcohol dehydrogenation route, suggesting towards lower selectivity in case of NODH of propanol. [ABSTRACT FROM AUTHOR]

Gas hydrates are crystalline compounds that are obtained from gas molecules trapped in cavities due to hydrogen bonding of water. Iran is among the countries that have rich reserves of natural gas and one of the issues related to the natural gas is gas hydrate formation that can cause problems in the oil and gas industry. However, in recent research hydrates' formation is mentioned as an advantage for specific uses. But this phenomenon occurred in natural gas transmission pipelines causes an increasing pressure drop, obstruction of gas transmission pipelines. The purpose of this study is to examine the natural gas hydrate formation in the presence or absence propanol as the thermodynamic inhibitor in a closed system experimentally. In this research, for the formation of gas hydrates, natural gas of the Gachsaran region of Iran and the Persian Gulf Seawater (instead of pure water) has been used. In this study, solutions containing inhibitors were examined in three weight percentages of 5, 15 and 25 and their results were also compared with each other. The results of the experiments showed that under identical conditions, Gachsaran natural gas hydrates are formed in the presence of Persian Gulf seawater at a lower temperature than pure water. It was also found that by increasing the concentration of inhibitor, the equilibrium temperature of hydrate formation is reduced and more equilibrium pressure is needed for hydrate formation. [ABSTRACT FROM AUTHOR]