Increasing Ethanol Concentration Research Articles

Production of bioethanol from unwashed-pretreated rapeseed straw at high solid loading

Reduction in water consumption and increase in ethanol concentration are two main challenges for bioethanol production from lignocellulosic materials. To address the two challenges, the aim of this work was to study the production of bioethanol from unwashed-pretreated rapeseed straw (RS) at high solid loading. RS pretreated with 1% (w w−1) H2SO4 at 160 °C for 10 min resulted in excellent digestibility and fermentability of pretreated RS. The unwashed-pretreated RS was subjected to presaccharification and fed-batch simultaneous saccharification and fermentation (P-FB-SSF) at a final solid loading of 22% (w w−1). Ethanol concentration and ethanol yield of 53.1 g L−1 (equivalent to 4.1% (w w−1) based on fermentation slurry) and 72.4% were obtained, respectively. In total, 92.1 g water g−1 ethanol was consumed, a much smaller amount than that observed with washing after pretreatment or fermentation performed at lower solid loading.

커먼레일 디젤기관에서 함산소 연료와 파일럿 분사시기의 변화가 연소 및 배기특성에 미치는 영향

In this study, the effect of various pilot injection timings on combustion and emission characteristics were investigated in a common-rail direct injection (CRDI) diesle engine fueled with diesel-ethanol blends. The engine speed and engine load were controlled at constant 1500rpm and 70Nm, respectively. The tested fuels were DE0 (pure diesel fuel), DE5 (5 vol.% ethanol blended with 95 vol.% diesel oil), DE10 (10 vol.% ethanol blended with 90 vol.% diesel oil) and DE15 (15 vol.% ethanol blended with 85 vol.% diesel oil). The main injection timing was fixed at 0°CA TDC (top dead center), while various pilot injection timings including 25°CA BTDC (before top dead center), 20°CA BTDC and 10°CA BTDC were selected as the experimental variable. The experimental results showed that various pilot injection timings had little effect on the peak value of cylinder pressure, but had great influence on the start of combustion. The peak value of heat release rate (HHR) increased with the increase of ethanol content. However, the peak value of HRR reduced as the pilot injection is delayed. The diesel fuel containing 10% ethanol had a highest peak value of combustion pressure compared with the others, while the pilot injection timing occurred at 25°CA BTDC. On the other hand, the exhaust emissions of DE10 was also the lowest compared with the others. In addition, with the increase of ethanol content in diesel the PM and NOx emissions reduced.

Simultaneous hydrogen and ethanol production in a thermophilic AFBR: a comparative approach between cellulosic hydrolysate single fermentation and the fermentation of glucose and xylose as co-substrates

This study evaluated the effect of hydraulic retention time (HRT) on the simultaneous hydrogen and ethanol production in two anaerobic fluidized bed reactors (55 °C) from mono-fermentation of cellulosic hydrolysate (AFBR-C) and the fermentation of glucose and xylose as co-substrates (AFBR-GX). In AFBR-C, the HRT was decreased from 24 to 8 h, while in AFBR-GX, the HRT was decreased from 16 to 0.5 h. The carbohydrate concentration was maintained at 4 g/L (AFBR-GX) and 2 g/L (AFBR-C). In AFBR-C, the main results observed by decreasing the HRT from 24 to 8 h were the increase in H2 yield (0.6–1.1 mol H2/mol hexose) and ethanol concentration (0.02–0.48 g/L). However, the H2 yield in AFBR-GX decreased from 0.4 to 0.1 mol H2/mol hexose by decreasing the HRT from 16 to 0.5 h. Additionally, the shortest HRTs applied to the AFBR-C (8 h) and AFBR-GX (0.5 h) resulted in the maximum hydrogen production rates of 115.7 and 279.9 mL H2/h L, the maximum energy yields of 7.4 and 47.7 kJ/h L, and EtOH molar fractions of 58.9 and 50.2%, respectively.

Electrosprayed whey protein-based nanocapsules for β-carotene encapsulation

In this work an electrohydrodynamic process (electrospray) was used to produce β-carotene loaded nanocapsules based on whey protein isolate (WPI). WPI solutions were prepared in aqueous solutions with different concentrations of ethanol (5, 10 and 15%) which were used for β-carotene solubilization. Different electrospray conditions were tested and the morphology and molecular organization of the nanocapsules were studied on dried and hydrated state. The size of the dried nanocapsules ranged between 227 and 283 nm. After hydration, there was a significant increase in the mean size of the nanocapsules, being the sizes higher for nanocapsules produced with increasing concentrations of ethanol. Results, obtained from the reactivity of free sulfhydryl groups and fluorescence analysis, showed that the increase of ethanol concentration had a destabilizing effect on the protein unfolding.Electrosprayed WPI-based nanocapsules can be used for the encapsulation of β-carotene answering the industrial demand for novel encapsulation technologies to protect sensitive bioactive compounds.

도라지(Platycodon grandiflorum) 꽃 주정 추출물의 이화학적 특성

The goal of this study was to investigate the physicochemical characteristics of Platycodon grandiflorum flower extracts obtained with different ratios of edible ethanol containing water solutions (10%, 30% and 60% ethanol). The redness and pH values of the extracts increased with increasing ethanol content, whereas the acidity decreased. The total phenol, total flavonoid, and total anthocyanin contents were in the ranges of 105.94-113.79 µg/mL, 11.97-27.13 µg/mL, and 0.01-0.13 µg/mL, respectively, all of which were significantly high and decreased in the order of 60% > 30% > 10% ethanol. The antioxidant activity and cholesterol adsorption activity generally followed the order of 60% > 10% > 30% ethanol, and the α-glucosidase inhibitory activity was significantly higher in the 10% ethanol extract, followed by the 30% > 60% ethanol extract. However, there was no identifiable significant difference in the xanthine oxidase inhibitory activities obtained using the different ethanol addition ratios when the sample concentration was 5 µg/mL. The physiological activities of the ethanol extracts of P. grandiflorum flowers are estimated to be affected by other functional components besides polyphenol compounds and anthocyanins because they were inconsistent with the trends of the total phenol, flavonoid, and anthocyanin contents.

Influence of Ethanol on Emulsions Stabilized by Low Molecular Weight Surfactants.

The effect of ethanol on oil‐in‐water emulsions stabilized with low molecular weight surfactants was investigated. Oil‐in‐water emulsions were prepared containing varying percentages of ethanol and sunflower oil, and stabilized with different emulsifiers (Tween 20, Tween 80, and Lecithin). Droplet size, viscosity, density, and interfacial tension measurements were carried out. The droplet size of emulsions stabilized by each of the surfactants studied decreased with the addition of ethanol to the aqueous phase showing a minimum at a concentration of ethanol around 40%. The trend in droplet size is accompanied by a decrease in the interfacial tension between water and oil as the ethanol concentration increases. Viscosity measurements show that the change in viscosity of the final emulsion is the result of the change in viscosity of the continuous phase, as well as the change in solubility of the surfactants due to the addition of ethanol. The density of the continuous phase decreases with the addition of ethanol and it is possible to match the densities of the two phases in order to reduce the effect of creaming/sedimentation and improve stability. This study provides scientific evidence for the formulation of stable emulsions containing a range of ethanol form 0 to 40%.Practical ApplicationFormation and stability of food‐grade emulsions in the presence of ethanol.

ETHANOL AS A MODIFIER OF RADIATION SENSITIVITY OF LIVING CELLS AGAINST UV-C RADIATION.

The protection of Escherichia coli bacteria and the yeast Saccharomyces cerevisiae against UV-C radiation by ethanol was studied. It was found that the fraction of surviving cells increases with increasing ethanol concentration. The specific protection depends on the dose rate, concentration range of ethanol, and it is higher for yeast compared to the bacteria.

Determination of Ethanol Content in Fuels with Phononic Crystal Sensor

Introduction. In-line analysis of ethanol content in gasoline blends is currently one of the urgent needs of fuel industry. Developing safe and secure approaches is critical for real applications. A phononic crystal sensor have been introduced as an innovative approach to high performance gasoline sensing. Distinguishing feature of proposed sensor is the absence of any electrical contact with analysed gasoline blend, which allows the use of sensors directly in pipelines without the risk of explosion in an emergency.Aim. Investigation of the possibilities of using phononic sensor structures to determine the ethanol content in liquid hydrocarbons.Materials and methods. A theoretical analysis of sensor structure was carried out on the basis of numerical simulation using COMSOL Multiphysics software. For measurement, substances of ordinary gasoline and gasoline 63–80 with ethanol concentrations in the range of 1–10 % by volume in increments of 2 % were prepared. The phononic crystal sensor was designed as a stainless steel plate with cylindrical holes and a resonant cavity, formed as a running across the wave propagation path slit between two lattices.Results. In-line analysis of measuring the concentration of ethanol in alcohol-containing fuels on a phononic crystal structure with a resonant cavity was carried out. Using the Agilent4395A admittance meter, the transmission spectra of longitudinal acoustic waves through the gasoline-filled sensor structure with were obtained. The non-linear correlation between the composition and the speed of sound of the blend is presented in the article is due to the ability to reduce the speed of sound of the mixture with an increase in ethanol concentration in the range of 0–10 % by volume.Conclusion. A measurement structure on the basis of phononic crystal was created. The measurements of various gasoline-ethanol mixtures show that the sensor has significant sensitivity (0.91 kHz/ms−1 ) with quality factor of 200) to distinguish between regular fuels, gasoline based blends and the presence of additives in standard fuels. The sensor has prospects for in-line analyzes the composition of liquid hydrocarbons.

Controlled gel research: the effect of ethanol for delaying the polycondensation of tetraethyl orthosilicate-dimethyldiethoxysilane

In this study, the effect of ethanol for delaying the polycondensation of silanol in the co-hydrolysis-condensation of tetraethyl orthosilicate-dimethyldiethoxysilane was first explored and demonstrated by varying the amount of ethanol under low-water content and acid-catalyzed. On the basis of this, the controllability of the sol-gel process is realized, and the calculation formula of the gel formation time is provided. The experiment shows that the storage gel time and the reaction gel time are extended from 75 h to at least 4584 h, or from 20 to 65 h with the increase of ethanol concentration, respectively. And we observed the microscopic process of solution-sol-gel transition by light transmission microscope. The sol-gel process established in this experiment gives a mechanism reference for future research.

Synthesis of ethanol perm-selective MFI zeolite membranes by binary structure directing agents

Good quality MFI zeolite membranes were prepared by altering a small amount of tetrapropylammonium (TPA+) with tetrabutylammonium (TBA+) in the synthesis solution. The effects of TBA+/Si ((TBA++TPA+)/Si ratio invariant) on the separation performance, hydrophobicity and compactness of MFI zeolite membranes were explored by pervaporation, water contact angle, scanning electron microscopy (SEM), X-ray diffraction (XRD), single-component gas permeation and permporosimetry. It was found that replacement of a small amount TPA+ with TBA+ could impair the hydrophobicity of membrane surface, but improve the membrane compactness verified by the ideal selectivity of N2/SF6 and permporosimetry. When TBA+/Si ratio increased to 0.02 from 0, the membrane separation factor was increased to 56 from 37 under crystallization time of 24 h, and 71 from 43 under crystallization time of 48 h. With increase of ethanol concentration in the feed from 1 to 50 wt%, the observed ethanol flux increased first and then decreased to that of single component pervaporation of ethanol, resulting in a peak value of the separation factor. The membrane M3 exhibited the highest separation factor of 79 with the flux of 1.40 kg m−2 h−1 for 3 wt% ethanol/water mixture while the highest separation factor of membrane M3-48 was 86 with the flux of 1.52 kg m−2 h−1 for 8 wt% ethanol/water mixture.

The control of paracetamol particle size and surface morphology through crystallisation in a spray dryer

The parameters governing the crystallisation of paracetamol using various conventional techniques has been extensively studied, however the factors influencing the drug crystallisation using spray drying is not as well understood. The aim of this work was to investigate the crystallisation of an active pharmaceutical ingredient through evaporative crystallisation using a spray dryer to study the physicochemical properties of the drug and to use semi-empirical equations to gain insight into the morphology and particle size of the dried powder. Paracetamol solutions were spray dried at various inlet temperatures ranging from 60 °C to 120 °C and also from a series of inlet feed solvent compositions ranging from 50/50% v/v ethanol/water to 100% ethanol and solid-state characterisation was done. The size and morphology of the dried materials were altered with a change in spray drying parameters, with an increase in inlet temperature leading to an increase in particle Sauter mean diameter (from 3.0 to 4.4 µm) and a decrease in the particle size with an increase in ethanol concentration in the feed (from 4.6 to 4.4 µm) as a result of changes in particle density and atomised droplet size. The morphology of the dried particles consisted of agglomerates of individual crystallites bound together into larger semi-spherical agglomerates with a higher tendency for particles having crystalline ridges to form at higher ethanol concentrations of the feed.

Ethanol Monitoring Gas Sensor Based on Flower-Shaped Copper Sulfide by a Facile Hydrothermal Method for Marine Transportation

Flower-shaped CuS as a p-type gas-sensing material was synthesized by a facile hydrothermal method in this study. Morphology, structure, and chemical composition of the synthesized CuS gas-sensing material were analyzed by SEM, XRD, XPS, and N2 adsorption adsorption–desorption technique. Gas-sensing properties of the as-prepared CuS sensors were also investigated toward ethanol monitoring. The results showed that the flower-like CuS nanostructures consisted of interconnected nanosheets and exhibited good crystallinity. With the increase in ethanol concentration, the sensitivity of the CuS sensor significantly increased and indicated a roughly linear relationship at the optimal operating temperature of 260 °C. The ethanol-selective characteristics of the CuS sensor against other interfering gases including methanol, benzene, dichloromethane, and hexane were studied, and the gas response of the CuS sensor synthesized at 170 °C toward 100 ppm ethanol was 5.22, which was significantly higher than all the other gases. Moreover, 14-day continuous measurement further confirmed the excellent stability of the CuS sensor.

Heat and mass transfer in the boundary layer during evaporation of aqueous solutions of ethanol and acetone into air and superheated vapor components of solutions

A stationary flow of three-component gas in a laminar boundary layer on a flat plate is considered at adiabatic evaporation of a two-component liquid film. Numerical modelling were carried out at atmospheric pressure, air flow velocity of 2 m/s and temperature from 20 to 500 °C in the whole range of concentrations of a low-boiling component of binary solutions: ethanol/water, acetone/water, and acetone/ethanol. Data on the local specific evaporation rate of ethanol/water and acetone/water solutions into dry air and superheated mixture of ethanol, acetone and water vapors were obtained depending on the temperature of the inlet flow. Composition of superheated vapor mixture was taken to be equilibrium relative to the liquid solution. With an increase in the molar fraction of ethanol or acetone in the water solution, the evaporation rate increases, and when evaporated into superheated vapor, the growth of evaporation rate with increasing vapor temperature is significantly higher than at evaporation into air. With an increase in ethanol or acetone concentration in the liquid solution, the inversion temperature decreases from down to 155…165°C.

Low concentration of exogenous ethanol promoted biomass and nutrient accumulation in oilseed rape (Brassica napus L.)

ABSTRACTWith hydroponics culture, we monitored the response of the growth and nutrient accumulation of oilseed rape (Brassica napus L.) to five ethanol concentrations: 0 mL•L−1 (control), 0.0125 mL•L−1, 0.025 mL•L−1, 0.05 mL•L−1, and 0.25 mL•L−1, respectively. The results showed that a high concentration of exogenous ethanol (0.25 mL•L−1) significantly inhibited oilseed rape growth by 52.28%. However, the biomass of oilseed rape with a low concentration of exogenous ethanol (0.0125–0.05 mL•L−1) manipulation was raised by 16.62–44.08%. A similar result was found on the total nitrogen, phosphorus, and potassium of the oilseed rape. Results of micro-element determination showed that iron and zinc accumulation in oilseed rape was unchanged, while manganese and copper accumulation was increased first and then decreased with increasing ethanol concentration. This study provided a possibility for improving plant growth with low concentration ethanol application in oilseed rape planting.

Study of solvation of substituted propylbenzene in ethanol-water solutions under subcritical conditions by molecular dynamics

Solutions of 2-methoxy-4-(2′-hydroxypropyl)phenol (PrPh) in water and water-ethanol mixtures (0.020, 0.115, 0.285 mol fraction of ethanol) at temperature 573 K and densities corresponding to an experimental pressure of 23 MPa have been simulated by molecular dynamics. Distribution of components in the fluid bulk and in the PrPh solvate shell has been researched. Numbers and lifetimes of hydrogen bonds between the components have been determined, and tendencies to selective solvation have been analyzed. It has been shown that PrPh molecules form stable long-lived hydrogen bonds with water and ethanol. An increase in ethanol concentration leads to a decrease in the number of hydrogen bonds formed by PrPh and to an increase in their lifetime that indicates growing stability of the solvate complexes. The local mole fraction of ethanol around PrPh is lower than its average mole fraction in the fluid, i.e., the PrPh solvate shells mainly consist of water molecules.

Evaporation of ethanol-water sessile droplet of different compositions at an elevated substrate temperature

We experimentally investigate the evaporation dynamics of sessile droplets with different compositions of ethanol-water binary mixture at different substrate temperatures. At room temperature, a binary droplet undergoes two distinct evaporation stages unlike only the pinned stage evaporation for pure droplets. In the binary droplets, the more volatile ethanol evaporates faster leading to a nonlinear trend in the evaporation process. At elevated substrate temperature, we observed an early spreading stage, an intermediate pinned stage and a late receding stage of evaporation. Increasing the substrate temperature decreases the lifetime of binary droplets rapidly. At high substrate temperature, we found that the lifetime of the droplet exhibits a non-monotonic trend with the increase in ethanol concentration in the binary mixture, which can be attributed to the non-ideal behaviour of water-ethanol binary mixtures. Interestingly, the evaporation dynamics for different compositions at high substrate temperature exhibits a self-similar trend showing a constant normalised volumetric evaporation rate for the entire evaporation process. This indicates that the evaporation dynamics of a binary droplet of a given composition at high substrate temperature is equivalent to that of another pure fluid with a higher volatility at room temperature. The evaporation rates of pure and binary droplets at different substrate temperatures are compared against a theoretical model developed for pure and binary mixture droplets. The model predictions are found to be quite satisfactory for the steady evaporation phase of the droplet lifetimes.

Chemical and sensory effects of cofermentation and post‐malolactic fermentation blending of Syrah with selected Rhône white cultivars

Background and Aims Whereas cofermentation is a traditional practice in some Old-World regions, its outcomes are largely unknown in New-World wine regions. Herein we report the chemical and sensory effects of cofermentation of Syrah with selected Rhône white cultivars. Methods and Results A Control wine comprising 100% Syrah (SY), and five SY blends [consisting of addition by mass of 10% pressed solids of Viognier (VG), Marsanne (MR), Roussanne (RS), Picpoul (PC), and Grenache Blanc (GB)] were produced. In addition, juice from each white cultivar was fermented separately and blended with finished SY wine at a rate of 10% after malolactic fermentation (MLF). Cofermentation had no effect on wine composition, but blending post-MLF increased ethanol concentration. Cofermentation resulted in lower concentration of most anthocyanin pigments, whereas blending post-MLF had the opposite effect. Tannins were higher in SY-VG, SY-RS and SY-MR blends, whereas polymeric pigments increased in SY-RS post-MLF and SY-PC post-MLF. This was attributed to enhanced copigmentation due to comparatively higher concentration of anthocyanins and flavonols in post-MLF blended wines, which resulted in a hyperchromic shift at 520 nm. Addition of VG, either as a coferment or as a blend post-MLF increased the aromatic complexity of the resulting wines. Conclusions Of the white cultivars studied, VG appeared to provide more aromatics both as a coferment or post-MLF blending option. Post-MLF blending gave increased aromatics and colour, while offering greater flexibility and fewer logistical issues than cofermentation. Significance of the Study The use of VG as the preferred coferment of SY, and the practice of post-MLF blending of SY with a small amount of white wine, were validated through chemical and sensory analysis.

Effects of Ethanol Concentration on Oral Aroma Release After Wine Consumption.

This paper evaluates, for the first time, the effects of ethanol concentration on the dynamics of oral (immediate and prolonged) aroma release after wine consumption. To do this, the intraoral aroma release of 10 panelists was monitored at two sampling points (0 and 4 min) after they rinsed their mouths with three rosé wines with different ethanol content (0.5% v/v, 5% v/v and 10% v/v) that were aromatized with six fruity esters (ethyl butanoate, isoamyl acetate, ethyl pentanoate, ethyl hexanoate, ethyl octanoate and ethyl decanoate). Overall, the results indicated that the extent of the effects of ethanol content on the oral aroma release were influenced by the subject, the ethanolconcentration and the type of aroma compound. This effect was also different in the immediate than in the prolonged aroma release. In the first in-mouth aroma monitoring, an increase in the ethanol content provoked a higher release of the more polar and volatile esters (ethyl butanoate, ethyl pentanoate), but a lower release for the more apolar and less volatile esters (ethyl octanoate, ethyl decanoate). Regarding the prolonged oral aroma release, an increase of ethanol content in wine increased the oral aroma release of the six esters, which might also increase the fruity aroma persistence in the wines. Future works with a higher number of individuals will be needed to understand the mechanisms behind this phenomenon.

Effects of ethanol on the efficiency of the formation of anodic alumina in sulfuric acid

In the interest of enabling practical applications of anodic oxide films, it is important to develop methods to improve the coulombic efficiency of film formation. In this study, ethanol was added to the sulfuric-acid-based electrolyte to examine its effects on the anodization behavior of aluminum, the maximum attainable film thickness, and the resulting etching ability. Anodization was conducted in sulfuric acid solutions containing various concentrations of ethanol under mild anodization conditions (i.e., 20 °C, as opposed to the lower-temperature hard anodization conditions). When a constant current of 100 A·m−2 was applied, the initial voltage and steady-state voltage were strongly dependent on the ethanol concentration that was added. The growth rate of the alumina film was governed by a field-assisted electrochemical process and, thus, was not affected by the addition of ethanol in the sulfuric-acid-based electrolyte. However, the maximum attainable film thickness increased with increasing ethanol concentration while the charge during anodization was constant. Thus, it was concluded the coulombic efficiency of the film formation could be improved by suppressing the chemical dissolution of the anodic film. Furthermore, the degree of acid dissociation in the water-and-ethanol system is thought to play an important role in controlling the formation and resultant structure of the film.

Metschnikowia pulcherrima Selected Strain for Ethanol Reduction in Wine: Influence of Cell Immobilization and Aeration Condition

One of the most important problems in the winemaking field is the increase of ethanol content in wine. Wines with high ethanol level negatively affect wine flavor and human health. In this study, we evaluated the use of a selected strain of Metschnikowia pulcherrima in immobilized form and under different aeration conditions, to reduce the ethanol content evaluating the volatile profile of the resulting wines. In a preliminary screening the best conditions regarding free/immobilized cells, static/aerated fermentation and inoculation level were identified. Bench-Top fermentation trials with different aeration conditions showed that the use of M. pulcherrima selected strain with aeration flow of 20 mL/L/min during the first 72 h of fermentation, led an ethanol reduction of 1.38% (v/v) in comparison with Saccharomyces cerevisiae control strain. The analytical profile of the resulting wines did not show any negative feature. Indeed, the concentration of ethyl acetate, that above its sensory threshold impacts negatively the wine sensory profile, was found at an acceptable level. On the other hand, an increase in the concentration of significant fruity and flower compounds was found.