Impurities In Ethanol Research Articles

Influence of Ethanol Grade on Captures of Ambrosia Beetles in Tree Fruit Orchards, Ornamental Nurseries, and Lumber Yards.

Ambrosia beetles, particularly invasive species within the tribe Xyleborini, such as Xylosandrus germanus (Blandford, 1894), pose significant threats to various ecosystems and managed habitats worldwide. Monitoring these invaders is vital for effective pest management, typically accomplished through ethanol-baited traps. We compared trap efficacy using denatured ethanol versus absolute ethanol in orchards, tree nurseries, and lumber yards in northeastern Ohio, USA, finding that absolute ethanol traps captured significantly more X. germanus. Analysis revealed acetone, ethanol, and methyl isobutyl ketone in the denatured ethanol, likely impacting trap efficacy. Our study underscores the importance of using pure denatured ethanol without acetone for effective monitoring, especially for X. germanus. Exotic xyleborines dominated trap captures across various habitats, emphasizing the need for tailored pest management strategies. Further research is warranted to explore the chemical ecology of ambrosia beetles and the influence of ethanol impurities on trap effectiveness.

Rapid detection of trace refrigerant impurities in low-temperature ethanol: A “background silence” method based on near-infrared spectroscopy

Low-temperature ethanol method is the main process for the preparation of blood products. Ethanol is cooled using plate heat exchangers with refrigerant fluid, and the ethylene glycol in the refrigerant is a toxic reagent, so the problem of refrigerant fluid leakage has become a concern for blood product companies. The lack of detection methods of refrigerant impurities in ethanol at this process stage can lead to serious safety issues and losses in the event of a refrigerant leak. In this study, a pattern recognition method based on near-infrared spectroscopy (NIRS), the “background silence” method, was developed for the detection of refrigerant impurities in ethanol. The method considered normal impurity-free ethanol solution samples as the background and impurity samples as the interference, made the background “silent” through linear regression, highlighted the changes brought by the interference factor, and then established a “background silence” pattern recognition system by calculating the RSD value at the characteristic data points, which realised the detection of trace refrigerant impurities in ethanol solution. The specificity and sensitivity of the method reached 100 %, and the detection limit can reach 0.25 ‰. The NIRS “background silence” method enables the detection of trace refrigerant impurities in ethanol solutions with reduced computational complexity compared with the widely used PLS-DA discrimination method. This study provides new methodological guidance for the detection of impurities in low content components, and lays the foundation for the application of the “background silence” method in practical production.

Multivariate optimization of a gas chromatographic method for the determination of organic impurities in ethanol

Medicinal ethanol obtained from alcoholic fermentation drags traces of organic impurities that have adverse effects in human health. For this reason, it is a priority to carry out a thorough examination of its composition before the final consumption. The identification of these compounds was performed by a gas chromatographic technique which was focused in the reduction of the applied temperatures, and in the minimization of gas consumption, by means of an experimental optimization of the parameters. The effect of six chromatographic parameters was studied over three desired responses. The four factors that did not influence the responses were the injector temperature, the FID temperature, sample injection volume and the hydrogen flow rate. As a consequence, the latter variables were set in their most conservative intervals considering the long life of the spare parts of the gas chromatograph.On the other hand, the starting run temperature and the linear velocity of the carrier gas were optimized to the final values of 49.16 °C and 35.00 cm/s, respectively, achieving a reduction of the run time from 34.96 to 21.38 min, without loss in the resolution between the first two peaks from 1.190 to 1.131. Moreover, the width of the last analyte peak significantly decreased from 0.310 to 0.212 min, and the signal/noise ratio was enhanced, hence improving the quantification of the analytes.

Investigation of the Conversion of Small Ethanol Impurities in Argon in Atmospheric-Pressure Glow Discharge

Investigation of the Conversion of Small Ethanol Impurities in Argon in Atmospheric-Pressure Glow Discharge

Подготовка тетраэтоксисилана для получения сферических частиц кремнезема. Часть 1. Ультрафильтрация

The paper considers the problem of instability of tetraethoxysilane hydrolysis in an ethanol medium in the presence of ammonia as a catalyst to obtain monodisperse spherical silica particles of a given size. This problem is associated with the presence of various impurities affecting rate of particle formation and, as a consequence, their size, monodispersity and shape. To solve this problem, we present novel studies of possible application of ultrafiltration for hydrolysis of initial tetraethoxysilane and ethanol through hydrophobic filters with a pore size of 50 nm. In both cases, we noted a decreasing intensity of light scattering after filtration. The elemental analysis of filtered impurities showed a significant content of SiO2 solid phases in tetraethoxysilane, and a number of impurities in ethanol. The experiments on the synthesis of silica particles from pre-filtered components showed that the resulting silica particles had a greater degree of monodispersity, and their sizes were much more reproducible, regardless of the used tetraethoxysilane. Thus, according to the obtained data, ultrafiltration is one of the effective ways to solve the problem of instability in the synthesis of monodisperse spherical silica particles.

Determining The Effect of Load on Synchronous Generator With Spark-Ignition Engine Energy Efficiency

Abstract The paper presents a new approach to energy indicator determination, such as specific fuel consumption and energy efficiency of the power plant. The essence of the new method is to determine the instantaneous power of the installation with subsequent data processing. The use of this method allows establishing the dependence of specific energy indicators on the generating unit load levels. The established distribution allows defining optimum parameters of experimental setup and consumption at various loading levels. The highest specific energy consumption of fuel is observed (1189–1297 g /(kW·h) and 962–1147 g / / kW·h)) at the lowest and the highest load for different fuels. Experimental data show that fuel without ethanol impurities can generate more electricity, which should be used at higher demand.

Experimental study on explosive boiling mechanism of superheated liquid containing ethanol impurities under rapid depressurization

In this study, a small visualization device was used to research the dynamic evolution of pressure reactions and bubble nucleation in tanks under rapid decompression. The effect of ethanol impurities on the mechanism of superheated boiling of liquids was investigated. The effect of ethanol impurities on the superheated boiling of liquids under different storage conditions is discussed by studying the pressure characteristic parameters. The experimental results show that ethanol impurities can reduce the bubble nucleation radius, leading to a sharp increase in the number of bubbles and more severe boiling during leakage. Besides, there is a saturation concentration which maximizes the promotion of superheated boiling of the liquid. Under the present experimental conditions, the boiling intensity of ethanol impurities saturates at 3.53%, and this saturation concentration decreases slightly with increasing initial leakage pressure. Ethanol impurities also promote boiling of superheated liquids at different initial liquid levels. This study can provide ideas for the investigation, analysis and prevention of related accidents.

The Influence of Ultrasound Cavitation on the Process of Degradation of Organic Substances in Wastewater of Pharmaceutical Production

The influence of ultrasound cavitation in the atmosphere of different gases, namely oxygen, air, and nitrogen, on the destruction of impurities of butanol and ethanol found in wastewater from the pharmaceutical plant “Galichpharm” was investigated. The effect of the corresponding gases (oxygen, nitrogen, and air) without ultrasound cavitation on the destruction of ethanol and butanol impurities in wastewater was comparatively investigated. The degree of oxidation of organic matter, effective rate constants, and approximation coefficients were calculated. It was found that the air supply is the least effective for both ethanol and butanol impurities. Degradation of ethanol by air contributed to the reduction in the organic matter content by 14.6 %, while oxidation of butanol was not observed. Ultrasound cavitation enhanced the effect of air and in common action with air the ethanol impurity content reduced by 32.58 %, and butanol impurity by 4.05 %. Nitrogen bubbling produced mediocre results for the destruction of ethanol and butanol impurities giving a decrease by 17.04 % and 0.67 %, respectively. The highest results were obtained with oxygen. Ethanol impurities decreased by 22.47 % and butanol impurities by 1.75 %. With the common action of oxygen and ultrasound, much higher results were obtained, 44.32 % for ethanol impurities and 7.43 % for butanol impurities.

Identification features of volatile impurities in ethyl alcohol using gas chromatographic retention indices

The restrictions of the commonly used determination algorithm of gas chro­matographic retention indices ( RI ) for the volatile impurities identification of ethyl alcohol being eluted prior to the principal constituent on the standard polar stationary phases (polyethylene glycols) are confirmed. The main reason of the­se restrictions seems to be the interfering n -alkanes С 6 – С 9 reference with the most of impurities. Due to this reason the identification of ethanol impurities to date preferably is based on comparing the profiles of chromatograms of target samples and those of model mixtures. It is shown that RI calculation in similar cases can be based on the data for the non-alkane reference constituents with known RI values that are always contained in the samples, namely acetone (RI 819 ± 6) and methanol (819 ± 6), in combination with the hold-up time value. Just the RI calculation permits us to reveal few groups of difficult to separate constituents as well as to identify some constituents previously not mentioned among ethanol impurities such as formaldehyde diethyl acetal (RI 860 ± 7) and ethyl vinyl ether (667 ± 10). The identification of ethyl vinyl ether is also confirmed by the analysis of the sample enriched with this ether in the result of the treatment of ethanol, containing small amounts of water, by calci­um carbide. In addition, the presence of ethyl vinyl ether is suggested in the sample of absolute ethanol prepared according to the known laboratory method by boiling with anhydrous cal­cium oxide. The evaluation of quantitative content of impurities is fulfilled using the internal standard method with acetone and methanol as standards. Keywords: Ethyl alcohol, impurities, gas chromatographic analysis, identification, vinyl ethyl ether, formaldehyde diethyl acetal (Russian) DOI: http://dx.doi.org/10.15826/analitika.2019.23.4.013 1 Alena I. Desyatova, 2 Nina G. Kovaleva, 3 Dmitrii A. Ponomarev, 1 Igor G. Zenkevich 1 St. Petersburg State University, Institute for Chemistry, Universitetskii prosp., 26, St. Petersburg 198504, Russian Federation 2 «Ekroskhim», Evpatoriiskii by-str., 7A, St. Petersburg 194044, Russia т Federation 3 St. Petersburg State Forest Technical University, Institutskii by-str., 5, St. Petersburg 194021, Russian Federation

Gas chromatographic determination of nonpolar impurities in ethanol and acetone using an aluminum oxide filled liner in the injector

Gas chromatographic determination of nonpolar impurities in ethanol and acetone using an aluminum oxide filled liner in the injector

Exploring the possibility of purification of water-alcohol solutions of different concentrations containing aldehydes and esters by mineral adsorbents

A comparative analysis of adsorption purification of water-alcohol solutions of different concentrations by clinoptilolite and shungite on the example of ethanol impurities such as acetaldehyde and ethyl acetate is carried out. Application of the aforementioned minerals for the adsorption of such simple substances as ethanol impurities is due to the previous positive results and the structure of the adsorbents investigated earlier. The optimum concentrations of water-alcohol solutions and the duration of contact of water-alcohol solutions with adsorbents for effective adsorption of aldehydes and esters are experimentally determined. The prediction of the efficiency of purification of polar impurities by mineral adsorbents based on the known rectification coefficients of the basic polar impurities is proposed. The higher the rectification coefficient, the lower the magnitude of hydrogen bonds of the impurity with ethanol and the easier it is to be sorbed from ethanol by mineral adsorbents. The relationship between the optimum concentration of water-alcohol solutions for effective adsorption of impurities and the rectification coefficient is shown. The expediency of using a mineral adsorbent such as clinoptilolite of Ukrainian origin instead of imported activated carbon in the production of alcoholic beverages is proved. It is determined that clinoptilolite is more useful as adsorbent for the purification of water-alcohol solutions containing aldehydes, which worsen the taste of alcoholic beverages most of all. It is shown that the use of clinoptilolite in the production of vodkas of underproof rectified alcohol will improve the taste of the final product.

Magnetic Field Effect on Photoinduced Electron Transfer Reaction Associated with Hydrogen Bond Formation in Homogeneous Medium

The effect of low magnetic field (MF) of the order of 0.01–0.08 T on the reactions involving spin-correlated radical ion pairs generated through electron transfer as intermediates is an interplay between diffusion dynamics and spin dynamics of the individual radical ions in the solvent cage. In this paper, we have made an attempt to study photoinduced electron transfer reactions between three aromatic amines and acridone in ethanol medium using a weak external MF. Although the MF effect is conventionally observed appreciably in heterogeneous organized medium, in the present case a considerable MF effect is obtained in homogeneous medium, i.e., ethanol. The occurrence of this rare phenomenon has been attributed to the presence of water molecules as impurities in ethanol.

Preconcentration of Impurities in Ethanol with the Use of Rayleigh Distillation

Preconcentration of Impurities in Ethanol with the Use of Rayleigh Distillation

Application of Gas Chromatography to the Identification of the Origin of Alcohols

The identification of ethanol of synthetic and biochemical origins was considered. Along with the determination of acetone, 2-butanol, methyl ethyl ketone, tert-butanol, crotonaldehyde, and other impurities in ethanol, it was proposed to use another criterion of the synthetic origin of ethanol, the isopropanol : methanol concentration ratio. The proposed criterion was applied to the gas-chromatographic analysis of various synthetic and biochemical samples of crude alcohols and rectified alcohols. Because isopropanol is difficult to remove by rectification, the proposed criterion for determining the origin of ethanol is applicable to not only crude alcohols but also rectified alcohols (as distinct from other criteria).

Mass Spectrometry of Impurities in Ethanol

Mass Spectrometry of Impurities in Ethanol