Characteristics Of Methanol Research Articles

Methanol infrared spectral characteristics in offshore gas logging

Methanol infrared spectral characteristics in offshore gas logging. Methanol was found in the logging gases during offshore gas logging by infrared spectra. Logging gas spectra from over 300 offshore wells and 1,000 onshore wells were processed and analyzed, and methanol characteristics were prevalent in the offshore logging gases but not onshore logging gases. The spectra of instruments Alpha111829 and Alpha111834 are studied as examples. The methanol concentrations in some areas exceeded 1 vol%, seriously interfering with the other measurements of alkane gases. Moreover, there are rapid changes in the trends of methanol concentrations. It indicates that methanol does not originate from drilling fluid additives. The results of the correlation analysis show that there are no strong correlations between methanol and the other logging gas component concentrations. Therefore, methanol may be neither a judgmental indicator component gas for natural gas nor oil but a separate energy source. We believe methanol in the offshore logging gases originates from strata. The discovery and analysis of methanol in offshore logging gases are significant in atmospheric and marine environments, oil and gas exploration, geochemistry, and energy.

Characteristics of Evaporating Spray for Direct Injection Methanol Engine: Comparison between Methanol and Diesel Spray

In the context of global efforts to pursue carbon neutrality, the research on the application technology of methanol fuel in internal combustion engines has ushered in a new peak. In order to provide a theoretical basis for the development of direct injection methanol engines, the spray characteristics of methanol with high-pressure direct injection were studied. Based on the visualization experimental device of constant volume vessels, the diffused background-illumination extinction imaging (DBI) and schlieren methods were applied to examine the distinctions in the evaporating spray properties between methanol and diesel under different injection pressures and ambient temperature conditions. Furthermore, aiming to maximize the potential of methanol fuel in compression ignition engines, under the premise that the alternative fuel can obtain the same total fuel energy as diesel, two different injection strategies of methanol were proposed and evaluated through the coordination of the nozzle hole diameter, injection pressure and injection duration. It reveals that it is easier for methanol spray to evaporate because of the lower boiling point, which results in a shorter spray tip penetration and wider spray angle compared with those of diesel, especially under the middle-level ambient temperature (600 K) condition. These deviations are also observed under different injection pressure conditions. However, affected by the lower energy density, the strategies of injecting the same fuel energy of methanol with that of diesel prolong the methanol spray tip penetration, enlarge its spray area and sacrifice the methanol evaporation performance. It is necessary for the geometrical design of the combustion chamber to coordinate with the hole diameter and injection pressure selection to deal with the huge distinctions in the spray characteristics between methanol and diesel fuel.

The Effect of Water Content on the Combustion Characteristics of Methanol in the Oxy-fuel System

The Effect of Water Content on the Combustion Characteristics of Methanol in the Oxy-fuel System

Analysis of carbon monoxide production in methanol steam reforming reactor for generating hydrogen

Seeking renewable energy sources has been a very important aspect in the development of human society, with many authors regarding hydrogen as a rather promising energy source. There are several forms of obtaining hydrogen, including steam reforming of hydrocarbons, alcohols, and ethers. Some characteristics of methanol, such as processing at mild temperatures from 250 to 350oC under atmospheric pressure and production from biomass – no competition for food production – have distinguished it from other alcohols for steam reforming. The great disadvantage of this technology when applied in proton exchange membrane (PEM) fuel cells is that the process of methanol steam reforming involves not only hydrogen and carbon dioxide, but also the production of a small amount of carbon monoxide, which is sufficient to affect the functionality of the fuel cells. This work presents the characterization of the catalyst HiFUEL R120 and shows how water/methanol molar ratio in the feed stream of an integral methanol steam reforming reactor influenced the conversion and the hydrogen selectivity in relation to carbon monoxide. This made it possible to identify the best operational conditions for lowering carbon monoxide content in the reactor effluent, avoiding the use of a CO purification unit.

Information system for molecular spectroscopy: 7—systematization of information resources on the main isotopologue of the methanol molecule

Systematization of information resources in quantitative spectroscopy is performed using the methanol molecule as an example and applying the facilities of the W@DIS information system (W@DIS IS). The choice of quantum numbers for a methanol state is explained; brief descriptions of about 40 publications containing spectral characteristics of methanol and the description of main applications of W@DIS IS are given. The interfaces used for the analysis of consistency of wavenumbers in all data sources are described, as well as the interface of the application for forming the list of measured transitions.

Experimental Studies on Burning Characteristics of Methanol, Diesel, and Sunflower Biodiesel Fuels

ABSTRACTThe combustion of liquid fuel droplets provides fundamental information that is relevant to spray combustion. A porous sphere setup has been used to investigate non-premixed combustion experimentally with three different liquid fuels, viz. methanol, diesel, and biodiesel (sunflower oil methyl ester). Experiments have been performed at atmospheric pressure with spheres of different diameters and over a range of free stream air velocities, resulting in different types of flames from envelope flame to wake flame. The measured mass burning rates are compared with the predictions from a theoretical model developed for envelope flames considering mixed convective transport. The model predictions are first validated for methanol and subsequently the model is applied for the other two fuels to evaluate their transfer numbers from the experimental mass burning rate data. A power law variation of nondimensional mass burning rate with effective Reynolds number (with contributions of forced and natural convection) is proposed for each of the fuels irrespective of sphere size and air velocity. The transition air velocities (from envelope to wake flames) for different fuels and the change in mass burning rate on transition are measured.

Homogeneous and heterogeneous catalysis production and evaluation of bio-diesel from Jatropha, neem and rubber seeds

Optimization of process parameters for producing biodiesel from Jatropha carcus, Azadirachta indica and hevea brasiliensis seed oils using homogeneous and heterogeneous catalyst were investigated. Temperature and methanol characteristics (oil molar ratio; catalyst type, concentration and agitation) controlled the ester convers-ion. A single-step and two-step trans-esterification were used to produce biodiesel from free fatty acid rubber, jatropha and neem seed oils. The maximum yields of ester from jatropha, neem and rubber oils were respective-ly 98.4, 94.6 and 92.8 % by homogeneous catalysis, and 79.0, 72.0 and 70.2 % by heterogeneous catalysis. While the homogeneous catalysis route produced higher biodiesel yields, the heterogeneous catalyst method produced biodiesel of lower ester content. The fuel properties of biodiesels and blends were analysed quantitati-vely, and the biodiesel produced by homogeneous catalysis compared favourably with conventional diesel fuel.

Investigation of interaction between methanol fed tandem porous spheres burning in a mixed convective environment

Flame interaction during the burning of two porous spheres in tandem arrangement fed with methanol and subjected to a mixed convective environment, has been studied experimentally and numerically. Porous sphere technique is employed for experimentally simulating the burning characteristics of methanol transpired spheres of different sizes, separated by fixed distances. The mass burning rates from both the spheres and visible flame stand-off distances from the sphere surfaces have been measured in the experiments. In the numerical simulations, transient, axisymmetric, mass, momentum, species and energy conservation equations are solved using a finite volume technique based on non-orthogonal semi-collocated grids. Features of the numerical model include finite rate chemistry and temperature and mixture composition dependent thermo-physical properties. Burning of tandem porous spheres in an air stream flowing vertically upwards, at atmospheric pressure has been simulated for different sphere sizes, separation distances and free stream velocities. The numerical predictions have been compared with experimental results. Results reveal that when two spheres burn one over the other, the transition from envelope to wake flame is delayed when compared with that of an isolated sphere. For two spheres of same diameter burning one over the other, depending on the separation distance, flame blows-off after the occurrence of transition from envelope to wake flame in the bottom sphere. For the case of larger sphere at the top, either the flame stabilises in the recirculation zone formed in between the spheres or the flame from the smaller sphere lifts off and stabilises near the front portion of the larger sphere, depending on the separation distance. At higher separation distances, around four times the diameter of the sphere, both the spheres burn independently. The burning rate undergoes complex variations with air stream velocity depending on the sphere sizes and separation distances.

Study of the spectroscopic properties and first hyperpolarizabilities of disperse azo dyes derived from 2-amino-5-nitrothiazole

The solvatochromism and other spectroscopic and photophysical characteristics of four azo disperse dyes, derived from 2-amino-5-nitrothiazole, were evaluated and interpreted with the aid of experimental data and quantum mechanical calculations. For the non-substituted compound two conformers, E and Z, were proposed for the isolated molecules, being the second one considerably less stable. The optimization of these structures in combination with a SCRF methodology (IEFPCM, simulating the molecules in a continuum dielectric with characteristics of methanol), suggests that the Z form is not stable in solution. This same behaviour is expected for the substituted compounds, which is corroborated by experimental data presented in previous investigations [A.E.H. Machado, L.M. Rodrigues, S. Gupta, A.M.F. Oliveira-Campos, A.M.S. Silva, J. Mol. Struct. 738 (2005) 239–245]. For the substituted compounds, two forms derived from E conformer ( A and B) are possible. Quantum mechanical data suggest for the isolated molecules, that the low energy absorption band of the E conformers involve at least two close electronic states, having the low-lying excited state a 1(n,π*) nature, and being the S 2 state attributed to a 1(π,π*) transition. The data also suggest a small energy gap between the absorption peaks of A and B, related to the easy conversion between these forms. For the structures optimized in combination with the applied SCRF methodology, an states inversion is observed for the substituted compounds, with a considerable diminish of the energy gap between A and B absorption peaks. The electronic spectra of these compounds are quite sensitive to changes in the solvent polarity. The positive solvatochromism is more evident in aprotic solvents, probably due to the polarization induced by the solute. These compounds do not fluoresce at 298 K, but present a small but perceptible fluorescence at 77 K, which seems to be favoured by the nature of the group in the 2′-position of the phenyl ring. Moreover, such compounds present expressive values for first hyperpolarizability, which implies in good non-linear optics (NLO) responses and photoswitching capability.

Calculation of the characteristics of ethanol and methanol adsorbed in a pore of activated carbon by the density functional method

Density functional theory was used to perform quantum-chemical calculations of changes in the energy and structure characteristics of methanol and ethanol molecules caused by their adsorption in model slitlike pores of activated carbon. The conclusion was made that changes in these characteristics (bond lengths, angles, charges on atoms, and harmonic vibration frequencies) is additional evidence of the validity of the Tolmachev thermodynamic model, in which adsorption is treated as a quasi-chemical reaction of the addition of adsorbate molecules to adsorption centers of an adsorbent. It was shown that the arrangement of alcohol molecules, when the C-O and C-C bonds were approximately parallel to pore walls and the hydrogen atom was directed toward a nearer pore wall, was most favorable energetically. Two adsorbed alcohol molecules are also arranged parallel to pore walls and form a hydrogen bond.

Spray characteristics of high-pressure swirl injector fueled with alcohol

The spray characteristics of methanol and ethanol with high-pressure swirl injector were explored experimentally and numerically. experimental results show that the spray characteristics of methanol and ethanol had displayed the same trends as that of gasoline. Under the low back-pressure ambient conditions, the spray behavior exhibited a hollow cone with wide spray angle and initial spray slug at the tip, while the spray presented a solid cone in the case of high back-pressure. Vortexes in the opposite direction existed in the rear part of the spray under low back-pressure ambient conditions while the vortexes formed in the middle part under high back-pressure ambient conditions. Experiments also showed that methanol had the largest cone angle, while ethanol and gasoline presented almost the same cone angle. Simulation results indicated that methanol and ethanol had a slightly larger Sauter mean diameter (SMD) than that of gasoline with swirl injector. The SMD profile of methanol coincided well with that of ethanol under low back-pressure ambient conditions, but displayed a slightly larger value under high back-pressure due to fuel evaporation Numerical simulation could successfully demonstrate the spray characteristics of high-pressure swirl injector for methanol and ethanol fuels.

An investigation of methanol and methanol blended sprays using laser scattering images

The characteristics of methanol and methanol blended (M85) sprays were investigated under atmospheric conditions at various temperatures, ranging from non-vaporizing to vaporizing ambient conditions (298–353 K). From laser scattering images, the macroscopic characteristics of the spray, such as the spray tip penetration and the spray angle, were determined. Entropy concept was introduced to represent homogeneity and PIV analysis was adopted to determine the fluid dynamic information at each location of the spray. The correlation between entropy and vorticity strength enabled us to find their relations. The effect of ambient composition, mainly of viscous effect as affected by CO2 levels, was investigated using PIV and entropy analysis. Spray width and entropy value were found to tend to decrease at increased CO2 levels.

Extended culture ofCandida boidinii on methanol

This paper deals with a specific technique of substrate feeding in methanol fermentation of the yeastCandida boidinii. The control loop is based on the measurement of methanol in the exhaust air. Experimental results from extended batch fermentations at different methanol concentrations are represented. A mathematical model including the inhibitory characteristics of methanol is compared with the experimental results. The effect of the inhibitory influence of methanol on the growth in continuous culture is discussed by means of a mathematical simulation.

Catalytic Decomposition and Anodic Current‐Potential Characteristics of Methanol on Active Palladium in Alkaline Solution

Methanol was found to decompose into hydrogen and on active palladium immersed in alkaline solution containing methanol. The hydrogen evolution rate was examined by using a hydrogen permeating foil electrode. From the concentration dependency of the evolution rate, the catalytic decomposition was found to proceed through the reaction, (liquid‐solid interface) and (gas‐solid interface). The current‐potential characteristics during anodic polarization recorded in the low current‐density region showed two steps, which could be elucidated by taking the above mechanism into consideration. Decomposition mechanism also dealt with standard potential.