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PubMed2001

Systematic bias in the measurement of water in oils by tubular oven evaporation and azeotropic distillation.

Water in oil has been measured by tubular oven evaporation and by azeotropic distillation into a coulometric moisture analyzer. The results of these measurements were compared to the results obtained by volumetric titration of water in oil. The volumetric measurements were consistently higher than the measurements made by tubular oven evaporation or azeotropic distillation. A mass balance study was performed by volumetric Karl Fischer titration of the water in the oil that remained in the tubular oven and in the distillation apparatus. This study indicated that measurable amounts of water were not removed after exhaustive evaporation or distillation. The sum of the water removed by distillation from toluene and that remaining in the distillation chamber was equal to the amount of water measured in the oil by the volumetric method. The data are consistent with the existence of an oil-water azeotrope that does not release water upon evaporation at 160 degrees C or upon dissolution in toluene and distillation of the water-toluene azeotrope. These results were obtained for oils varying in viscosity from 8 to 850 m2/s, and the amount of water remaining associated with the oil appears to be dependent upon the composition of the oil and the method of analysis.

Journal Article↗

PubMed2003

Real-time monitoring of distillations by near-infrared spectroscopy.

A simple device is described to couple a fast-scanning acoustooptic tunable filter-based NIR spectrophotometer to a distillation apparatus for monitoring the condensed vapor in real time. The device consists of a small funnel whose glass neck (2-mm diameter) is bent into an "U" format to produce a flow cell of approximately 150-microL inner volume. A pair of optical fibers is used to deliver the monochromatic light and to collect the fraction passing through the glass tube. The end of the condenser of the distillation head touches the wall of the small funnel. The condensed liquid flows uncoupled from pressure changes in the interior of the distillation head. Absorbance spectra were obtained, during the distillation, as averages of 50 scans (4 s) every 5 s in the spectral range 950-1800 nm with nominal resolution of 2.0 nm. In the first experiments, the distillations were performed at constant power supplied to the sample (25 mL) in a microdistillation apparatus working without any type of reflux column. The usefulness of the real-time monitoring of distillation is demonstrated using some prepared binary mixtures and by comparing the distillation behavior of adulterated and regular gasoline samples. Data analysis and interpretation are facilitated by employing principal component analysis. The system accesses the composition of the condensate, which can separate and concentrate one or more compounds present in the original sample.

Journal Article↗

PubMed2005

Life-cycle inventory of waste solvent distillation: statistical analysis of empirical data.

Distillation is one of the most important processes in the chemical industry. An environmental assessment of distillation processes is difficult because of the highly specific features of each distillation process. Life-cycle inventory (LCI) information is therefore scarce. The goal of this paper is to provide reliable data ranges for inventory flows of waste solvent distillation (i.e. amount of recovered distillate, consumption of steam, electricity, nitrogen, cooling water and ancillary product, and the generation of organic waste, wastewater, and outlet air). For this purpose, we collected data from approximately 150 waste solvent distillation processes from chemical industry and analyzed them statistically. The results of the statistical analysis compose generic data ranges for each LCI parameter. Where appropriate, the data of each LCI parameter have been subdivided according to the distillation technology or the waste solvent composition. Additionally, probability distributions have been fitted to the data of each LCI parameter, thus enabling quantitative uncertainty analysis (e.g. Monte Carlo Simulation). In a case study we illustrate the application of the inventory data ranges according to situations of differing data availability.

Chemical Industry↗

PubMed2003

Influence of distillation system, oak wood type, and aging time on volatile compounds of cider brandy.

A study of the influence of distillation system, oak wood type, and aging time on volatile compounds of cider brandy was carried out. Acetaldehyde and acetaldehyde diethyl acetal were influenced by distillation technology, oak wood type, and maturation time. The majority ester, ethyl ethanoate, increased during aging, the highest level of this ester being detected in spirits distilled by double distillation. The alcohols of higher molecular weight were better recovered in the rectification column than in the double distillation system. Ethanoate esters decreased throughout aging of the spirits, and their degradation velocity was lower in distillates obtained from double distillation. Fatty acids and their ethyl esters presented the opposite evolution during aging, detecting an increase in ethyl esters and a decrease in their corresponding fatty acids. An increase of 1,1,3-triethoxypropane was detected during aging. French oak contributes the trans isomer of beta-methyl-gamma-octalactone and American oak contributes the cis isomer.

Acetaldehyde↗

PubMed2000

Fractional distillation of acid contaminants from sevoflurane.

On two occasions, sevoflurane distributed for clinical practice has been found to be contaminated with compounds thought to include hydrogen fluoride (HF) and silicon tetrafluoride (SiF(4)). Both compounds can produce pulmonary injury. However, injury would require fractional distillation of the compounds during the course of sevoflurane vaporization. We hypothesized that such distillation would occur and that the compounds would vaporize more rapidly than would sevoflurane. Thus, we tested whether fractional distillation occurs during vaporization of sevoflurane containing HF or SiF(4), or from sevoflurane containing HF converted to other compounds by contact with glass. Vaporization of < 10% of the sevoflurane distilled 65%-99% of these compounds, SiF(4) distilling most rapidly, HF (converted to other acidic compounds, including SiF(4)) distilling nearly as rapidly, and HF slowest. Nuclear magnetic resonance studies indicated that HF interaction with glass changed all HF to three other compounds, one being SiF(4) and the others being unknown. HF and SiF4 distill from sevoflurane more rapidly than sevoflurane is vaporized. Measurement of acidity after sevoflurane administration may not reveal a previous presence of such contaminants.

Acids↗

PubMed1986

Bronchoconstriction induced by distilled water. Sensitivity in asthmatics and relationship to exercise-induced bronchospasm.

We studied the ability of bronchial challenge with an ultrasonically produced, distilled water aerosol to detect airways hyperreactivity in asthmatics and also evaluated its relationship to exercise-induced bronchoconstriction. Fifteen asthmatics and 10 normal subjects inhaled, at room temperature, distilled water aerosol in increasing concentrations. On a separate day, each subject performed a standard methacholine challenge. On the third day, all asthmatics exercised on a treadmill for 6 min at 90% maximal heart rate while breathing room-temperature, dry air. Pulmonary mechanics (FEV1 and SGaw) were measured before and after each challenge. Seven of the asthmatics and all of the normal subjects did not react to challenge with distilled water. Distilled-water challenge caused a 20% decrease in FEV1 in only 53% (8 of the 15) asthmatics, whereas all of the asthmatics reacted to methacholine challenge with a 20% fall in FEV1. Thus, distilled water was not a sensitive challenge procedure for the detection of airways hyperreactivity in asthma and it cannot be used as a routine screening test. However, in the asthmatics, the response to distilled water challenge correlated significantly with the response to exercise (r = 0.81, p less than 0.001). Seven asthmatics were reactive to both exercise and water, 7 were reactive to neither exercise nor water, and 1 reacted to water but not to exercise. Cromolyn completely or partially blocked both distilled-water- and exercise-induced bronchospasm in the reactive asthmatics.(ABSTRACT TRUNCATED AT 250 WORDS)

Aerosols↗

PubMed1995

Changes in sensitivity to methacholine after inhalation with distilled water: the role of the bronchoconstrictive response.

The inhalation of distilled water can induce bronchoconstriction and a transient increase in sensitivity to methacholine in asthmatics. The purpose of this study was to determine the role of the induced bronchoconstriction in the increased sensitivity to methacholine which follows the challenge with distilled water. Eighteen asthmatic children (age 9-17 yrs) were challenged by inhalation of distilled water. Bronchial responsiveness, the provocative concentration of methacholine producing a 20% decrease in forced expiratory volume in one second (PC20), was determined before inhalation of distilled water, and 1.5 and 24 h thereafter. Following inhalation of distilled water, eight patients (Group I) had a greater than 15% decrease in FEV1 (mean 23%); whereas, in the remaining 10 (Group II) the decrease was less than 7% (mean 1%). PC20 to methacholine, geometric mean and 95% confidence interval (CI), decreased transiently only at 1.5 h following inhalation of distilled water. The decrease was from 0.78 mg.ml-1 (95% CI 0.11-5.54 mg.ml-1) at baseline to 0.25 mg.ml-1 (95% CI 0.03-2.14 mg.ml-1) after challenge in Group I; and from 2.67 mg.ml-1 (95% CI 0.35-20.34 mg.ml-1) at baseline to 0.72 mg.ml-1 (95% CI 0.18-14.87 mg.ml-1) after challenge in Group II. The transient increase in sensitivity to methacholine observed following inhalation of distilled water occurred independently of the bronchoconstrictive response. This finding may have important clinical implications when hypo-osmolar solutions are used for delivery of drugs.

Adolescent↗

PubMed1986

Comparison of bronchial responses to ultrasonically nebulized distilled water, exercise, and methacholine in asthma.

We compared the responses to inhaled methacholine, ultrasonically nebulized distilled water, and exercise in 25 subjects with atopic asthma. The methacholine inhalation test and challenges with distilled water and exercise were performed on three separate days 48 hours apart. Bronchial responsiveness to methacholine and ultrasonically nebulized distilled water was measured as the concentration of methacholine (PC20M) and the volume output of the ultrasonic nebulizer (PO20 UNDW) producing a 20 percent fall in the forced expiratory volume in one second (FEV1). The response to exercise was expressed as the percentage of fall in FEV1 from the value before exercise. Seventeen subjects showed a fall in FEV1 of more than 20 percent after exercise. Eight subjects had a stimulus-response curve to distilled water that was flat up to the maximal volume output from the nebulizer, but only four of them also showed no significant response to exercise. The response to exercise correlated better with PO20 UNDW (r = -0.66; p less than 0.01) than with PC20M (r = -0.19; p greater than 0.5) in those responding to distilled water. In all of the tested subjects, exercise-induced bronchoconstriction correlated with PC20M (r = -0.61; p less than 0.01). The mean PC20M was significantly lower in the subjects with a significant response to distilled water and exercise (p less than 0.001 and p less than 0.0001, respectively). We concluded that ultrasonically nebulized distilled water and exercise provoke significant bronchoconstriction in the subjects with more severe nonspecific bronchial hyperresponsiveness. The correlation found between the two stimuli supports the hypothesis that they act by similar mechanisms.

Adolescent↗

PubMed1993

Feeding value of wet distillers byproducts for finishing ruminants.

Yearling and calf finishing trials (replicated over 2 yr) evaluated the feeding value of wet distillers byproducts (wet distillers grains and thin stillage). An additional trial estimated the amount of thin stillage bypassing the rumen when consumed by drinking. Yearlings were 5, 10, and 20% more efficient (linear, P < .01; quadratic, P = .05), whereas calves were 2, 6, and 14% more efficient (linear, P < .01) when fed 5.2, 12.6, and 40.0% (DM basis) wet distillers byproducts, respectively, compared with cattle fed a 79% dry-rolled corn diet. Cattle fed 5.2 or 12.6% wet distillers byproducts, or the dry-rolled corn diet, received similar amounts of protein (crude or metabolizable), which exceeded the metabolizable protein requirement of all cattle. Therefore, differences in efficiency were attributed to differences in energy utilization of the diets. Wet distillers byproducts fed at 5.2, 12.6 and 40.0% contributed 80, 62, and 47% more net energy for gain than corn when fed to yearlings and 17, 33, and 29% more net energy for gain than corn when fed to calves, respectively. Wet distillers byproducts averaged 169% the energy value of corn (2.53 Mcal of NEg/kg) when fed to yearlings and 128% the energy value of corn (1.96 Mcal of NEg/kg) when fed to calves. The increased energy values cannot be explained by increased digestibility, but they may be due to a combination of factors (reduced acidosis, increased energy utilization, yeast end products, etc.) that increase the net energy content of distillers byproducts. Approximately 50% of the thin stillage consumed by drinking bypassed ruminal fermentation.(ABSTRACT TRUNCATED AT 250 WORDS)

Animal Feed↗

PubMed1997

Evaluation of wet distillers composite for finishing ruminants.

Two trials evaluated the effect of a composite of feed ingredients formulated to be similar in nutrient composition to wet distillers byproducts on finishing performance of sheep and cattle. Trial 1 used 60 crossbred lambs (31 kg) assigned to one of four treatments: dry-rolled corn (DRC) control, dried distillers grains plus solubles, wet corn gluten feed (WCGF), and wet distillers grains composite (COMP1). The COMP1 consisted (DM basis) of 47.5 WCGF, 11.9% condensed distillers solubles, 30.5% corn gluten meal, 9.7% tallow, and .4% dicalcium phosphate and was fed at 40% of the diet DM. Lambs fed the COMP1 diet were 27% more efficient (P < .10) than lambs fed WCGF and 12% more efficient (P > .10) than lambs fed DRC. In Trial 2, 60 yearling crossbred steers (272 kg) were assigned to one of five treatments: DRC control, WCGF, wet distillers grains composite (COMP2), COMP2 minus tallow (-FAT), or COMP2 minus corn gluten meal (-CGM). the COMP2 consisted (DM basis) of 65.7% WCGF, 26.3% corn gluten meal, and 8.0% tallow and was fed at 40% of the diet DM. Steers fed COMP2 were more efficient (P < .10) than steers fed DRC or WCGF, and the steers fed -FAT and -CGM were intermediate to these three dietary treatments. A composite diet of WCGF, condensed distillers solubles, corn gluten meal, and tallow, formulated to be similar in nutrient composition to wet distillers byproducts, may improve feed efficiency compared with WCGF or DRC.

Animals↗

PubMed2004

Growth performance of nursery pigs fed diets containing increasing levels of corn distiller's dried grains with solubles originating from a modern Midwestern ethanol plant.

Two experiments were conducted to determine the effects of including distiller's dried grains with solubles in nursery diets on growth performance, and to establish maximum inclusion rates for corn distiller's dried grains with solubles originating from modern, "new-generation" ethanol plants (built since 1990). Ninety-six crossbred pigs (BW = 6.18 +/- 0.14 kg) were blocked by gender and ancestry, and pigs within each block were randomly assigned to one of six dietary treatments (four pigs/pen, four pens/dietary treatment) in each of two growth performance experiments. Dietary treatments provided 0, 5, 10, 15, 20, or 25% distiller's dried grains with solubles during Phases 2 and 3 of a three-phase nursery feeding program for early-weaned pigs. Pigs in Exp. 1 were slightly older (19.0 vs. 16.9 d of age) and heavier (7.10 vs. 5.26 kg) at the beginning of the experiment compared to pigs in Exp. 2. All pigs in both experiments were provided a commercial pelleted Phase 1 diet for the first 4 d after weaning and were then switched to their respective experimental Phase 2 diets, which were fed for 14 d, followed by their respective Phase 3 experimental diets, which were fed for a subsequent 21-d feeding period. Experimental diets were formulated to contain equivalent apparent ileal digestible lysine (1.35 and 1.15%), apparent ileal digestible methionine + cystine (0.80 and 0.65%), ME (3,340 and 3,390 kcal/kg), calcium (0.95 and 0.80%), and total phosphorus (0.80 and 0.70%) within Phases 2 and 3, respectively. Overall growth rate, ending body weight, and feed conversion were similar among pigs regardless of dietary distiller's dried grains with solubles level for both experiments. In Exp. 1, feed intake was not affected by dietary treatment (P > 0.10). In Exp. 2, however, increasing the level of distiller's dried grains with solubles linearly decreased feed intake (P < 0.02) during Phase 2 and tended to decrease voluntary feed intake (P < 0.09) over the length of the experiment. These results suggest that the corn distiller's dried grains with solubles used in this study can be included in Phase 3 diets for nursery pigs at dietary levels of up to 25% without negatively affecting growth performance after a 2-wk acclimation period. Including high levels of corn distiller's dried grains with solubles in diets for pigs weighing less than 7 kg in BW, however, may negatively influence feed intake and growth.

Aging↗

PubMed1998

Evaluation of corn distillers grains and ruminally protected lysine and methionine for lactating dairy cows.

Twelve multiparous Holstein cows averaging 57 d (36 to 77 d) postpartum at the start of the experiment were utilized in a replicated 4 x 4 Latin square design. Dietary protein supplements were 1) soybean meal, 2) soybean meal plus ruminally protected Lys and Met, 3) corn distillers grains, and 4) corn distillers grains plus ruminally protected Lys and Met. Dry matter intakes were lower for cows fed diets containing soybean meal than for cows fed diets containing corn distillers grains. Milk yield increased with the corn distillers grains (34.3, 34.0, 35.3, and 36.7 kg/d for cows fed diets 1 through 4, respectively), especially when supplemented with ruminally protected Lys and Met. Milk protein yield and percentage were increased by amino acid supplementation. Milk fat yield and percentage were unaffected by diet. The only milk protein fraction affected was nonprotein N, which was lower in the milk of cows fed corn distillers grains. Lysine, Met, and Phe were indicated as the most limiting amino acids for all diets when using amino acid extraction efficiency and transfer efficiency to indicate limiting amino acids. When corn distillers grains were supplemented with ruminally protected Lys and Met, milk yield and milk protein yield and percentage increased because the diet containing corn distillers grains was probably deficient in Lys.

Animal Nutritional Physiological Phenomena↗

PubMed2003

Recovery of acetic acid from waste streams by extractive distillation.

Wastes have been considered to be a serious worldwide environmental problem in recent years. Because of increasing pollution, these wastes should be treated. However, industrial wastes can contain a number of valuable organic components. Recovery of these components is important economically. Using conventional distillation techniques, the separation of acetic acid and water is both impractical and uneconomical, because it often requires large number of trays and a high reflux ratio. In practice special techniques are used depending on the concentration of acetic acid. Between 30 and 70% (w/w) acetic acid contents, extractive distillation was suggested. Extractive distillation is a multicomponent-rectification method similar in purpose to azeotropic distillation. In extractive distillation, to a binary mixture which is difficult or impossible to separate by ordinary means, a third component termed an entrainer is added which alters the relative volatility of the original constituents, thus permitting the separation. In our department acetic acid is used as a solvent during the obtaining of cobalt(III) acetate from cobalt(II) acetate by an electrochemical method. After the operation, the remaining waste contains acetic acid. In thiswork, acetic acid which has been found in this waste was recovered by extractive distillation. Adiponitrile and sulfolane were used as high boiling solvents and the effects of solvent feed rate/solution feed rate ratio and type were investigated. According to the experimental results, it was seem that the recovery of acetic acid from waste streams is possible by extractive distillation.

Acetic Acid↗

PubMed2006

[Application of distilled water in sperm counting and hypoosmotic swelling test].

OBJECTIVE: To evaluate the application of distilled water in sperm-counting and hypoosmotic swelling test. METHODS: Thirty-seven semen samples were collected and each was diluted by distilled water and sodium acid carbonate-formaldehyde solution, respectively. Then the hemacytometer was used for sperm counting. Meanwhile, the percentage of swelled sperm diluted by distilled water was compared with the result of hypoosmotic swelling test recommended by WHO. Another 26 semen samples were diluted by distilled water and hypoosmotic swelling solution respectively, and the percentages of the swelled sperm were compared. RESULTS: There was no significant difference either between the sperm concentrations obtained by distilled water and sodium acid carbonate-formaldehyde solution (P > 0.05) or between the percentages of the swelled sperm diluted by distilled water and hypoosmotic swelling solution. CONCLUSION: Distilled water can not only replace sodium acid carbonate-formaldehyde solution for sperm-counting dilution but also be used as a hypoosmotic swelling solution.

Adult↗

PubMed1979

Investigation and simplification of the sweep co-distillation cleanup of pesticide residues in animal fats.

The sweep co-distillation technique of Storherr et al. was investigated and simplified. Six organochlorine pesticides in animal fats were cleaned up under various distillation conditions as follows: No solvent was used, or solvent injection rates were 1 mL/min or 2 mL/3 min. Distillation tubes of 6.7 and 9.0 mm id diameter were compared. Distillation temperatures were varied from 150 to 300 degrees C. The complex condenser of Storherr et al. was compared with a simpler pipet condenser. A U-tube condenser which allows direct introduction onto a Florisil column for secondary cleanup was evaluated. The following modifications to the sweep co-distillation technique resulted: no solvent introduction, distillation temperature 230 degrees C, nitrogen flow rate 600 mL/min, 6.7 mm id distillation tubes with simplified packing, and incorporation of the U-tube condenser. The new technique gave recoveries comparable to those of Storherr et al., but it is faster than most bisolvent partition methods and no large volumes of solvent are required.

Animals↗

PubMed2005

Wine distillates: practical operating recipe formulation for stills.

Consumer perceptions of flavors are associated with the chemical composition of foods. However, consumer preferences change; therefore, it is necessary for food manufacturers to be able to adapt their products. Unlike in aged spirits, the chemical composition of young spirits is determined during distillation; therefore, this is where distillers must tailor their operating recipes to the new trends. Even for an experienced distiller, the complexity of the process makes adapting the operating recipe far from straightforward. In this study, we developed a methodology for generating practical recipes that makes use of computer simulations and optimization techniques. We used Pisco Brandy, a young Muscat wine distillate from Chile and Peru as our case study. Even so, because our methodology is independent of the chemical composition of the broth, it can be applied throughout the industry. Drawing on the experience and preferences of industry enologists, we designed a preferred distillate and used our methodology to obtain the appropriate recipe. This recipe was validated in lab scale experiments, and we obtained a much closer distillate to the desired prescription than commercial products.

Alcoholic Beverages↗

PubMed2006

Influence of the distillation step on the ratios of stable isotopes of ethanol in cherry brandies.

Isotope ratio mass spectrometry and site-specific natural isotope fractionation-nuclear magnetic resonance were applied to determine the overall carbon isotope ratio (delta13C) and the hydrogen isotope ratios [(D/H)I and (D/H)II] of ethanol, respectively. Ethanol was obtained by distillation of fermented cherry mash from a pot still commonly used in fruit brandy production. Analyses of distillate fractions revealed that the distillation proceeds with a fractionation of ethanol isotopologues. The inverse vapor pressure isotope effect (VPIE) observed for the carbon isotopologues is in accordance with the data reported for distillation of ethanol in spinning band columns. In contrast, the inverse VPIE for hydrogen isotopologues of ethanol observed in spinning band columns could not be confirmed. To investigate whether the observed isotope fractionations might influence the applicability of stable isotope analysis for quality and authenticity assessment of fruit brandies, the collected distillate fractions were recombined to cuts, as is common practice in commercial fruit brandy production. Taking into consideration the limits of repeatability of the method, it could be demonstrated that the isotope fractionations observed do not impair the applicability of stable isotope analysis of the carbon and hydrogen isotopes of ethanol for the authenticity assessment of cherry brandies if the cuts are placed in accordance with common distillers' practice.

Alcoholic Beverages↗

PubMed2000

A comparison of distilled water and normal saline as diluents for endobronchial administration of epinephrine in the dog.

UNLABELLED: We compared the effects of distilled water and normal saline as diluents for the endobronchial administration of epinephrine in anesthetized dogs by using a cross-over design. Six dogs received 2 mL of either normal saline or distilled water into the bronchus, and the other solution was administered 1 wk later. Eight dogs received 0.02 mg/kg epinephrine diluted in either distilled water (E + water) or normal saline (E + saline) to a total volume of 2 mL into the bronchus, and the other solution was administered 1 wk later. Normal saline or distilled water without epinephrine did not affect the plasma epinephrine concentration, mean arterial pressure (MAP), and PaO(2). The peak plasma epinephrine concentration was significantly larger after treatment with E + water (26.5 +/- 7.9 ng/mL) than after E + saline (2.1 +/- 0.7 ng/mL). E + water caused an increase in MAP of 91 +/- 24 mm Hg, whereas E + saline did not affect MAP. The maximal decrease in PaO(2) after the administration of E + water (14 +/- 5 mm Hg) was significantly greater than after E + saline (7 +/- 2 mm Hg). In conclusion, distilled water as the diluent for endobronchially administered epinephrine to a total volume of 2 mL allowed better absorption of epinephrine compared with normal saline without a serious detrimental effect on PaO(2). IMPLICATIONS: Using a small volume of distilled water as the diluent for endobronchial epinephrine administration significantly increased epinephrine absorption and arterial pressure in comparison with normal saline, without having a serious detrimental effect on PaO(2), in an anesthetized, noncardiopulmonary, resuscitation dog model.

Animals↗