Steam distillation, solvent extraction, and ion exchange for determining polar organics in shale process waters

Abstract

Steam dlstlllatlon, solvent extraction, and ion exchange procedures have been employed to isolate volatile organlc ackls, bases, and neutral compounds from process waters generated durlng the retortlng of oil shale. Gas chromatography was used for the analysis of the Isolated components and for the dlrect analysis of the process waters. The use of these multiple isolation and analyses procedures has resulted In the determlnatlon of the foilowlng compounds wlth the amounts In ug/mL given in parentheses: 12 C2 to C,o aliphatlc acids (26 to 450); phenol (21); pyridine (5); five methyl substttuted pyrldlnes (3 to 19); aniline (2); isoquinoline (2); four C, to C, n-alkylamlnes ( 2 to 10); three C, to C, n-aikylnltriies ( 1 to 21); benzonltrlie (3); formaldehyde (500); acetaldehyde (2); propanone (16); and butanone (6). The advantages of steam dlstiliatlon and ion exchange for the isolation and eventual anaiysls for water containlng complex mixtures of volatile acidic, basic, and neutral organlc components are described.The retorting of oil shale leads to a process water containing a complex mixture of acidic, basic, and neutral organic compounds. Raphaelian and Harrison ( 1 ) have identified 160 different components and Pellizzari and his colleagues (2,3) have reported qualitative and quantitative data for 97 organic compounds in oil shale process waters. These researchers used solvent extraction and purge and trap procedures to isolate the organic compounds from the process water. These procedures are efficient for nonpolar, low solubility compounds ( 4 5 ) but are less effective for polar components especially those having high solubility in water. These hydrophilic compounds are frequently isolated by less general, but potentially more efficient procedures, such as distillation (6-1 l ) and ion exchange (1 2,13).Steam distillation, using standard procedures (6, 7), has been investigated thoroughly for the isolation of fatty acids and phenols from wastewaters and other aqueous samples. It has also been shown to be efficient for neutral hydrophilic compounds (8,9). Direct distillation of aqueous samples has also been successful for neutral components (10) and for volatile amines ( 1 1 ) . Other basic components have not been investigated but distillation procedures should be generally applicable to all polar, acidic, and basic organic compounds of reasonable volatility.Polar organic compounds that form anions and cations in water can also be isolated by ion exchange procedures and recent reports (12,1#3) suggest general applicability to organic acids and bases.An alternative to isolating the organic compounds is the direct analysis of process water using gas chromatography (GC) with stationary phases that are tolerant of the water matrix. This procedure is effective if the concentrations of the organic compounds are near or above 1 ppm and other organic and inorganic components in the water do not cause rapid deterioration of the GC column used for the separation.Our analysis of oil shale process waters using the iso...

Sensory GC analysis of decaying vegetation and septic odors

“…For example, high extraction recoveries have been reported for volatile organic compounds found in beer 17 . Other researchers have successfully used the method to extract fatty acids, phenols, and other compounds found in water 18 . The glassware obtained for this study was specifically designed for SDE use *…”

Sample Preparation for Chromatographic Analysis

“…Solvent extraction and gas phase stripping methods are generally inefficient procedures for isolating polar, acidic, or basic compounds in an aqueous matrix due to the low efficiency of water immiscible solvents for the extraction of these compounds and their low volatility and high water affinity which results in a very slow transfer to the gas phase using sparging techniques. The recovery of organic volatiles may be changed by simultaneous gas sparging, addition of a large amount of an inorganic salt, by pH adjustment, or by the addition of a codistiller, such as benzene or toluene [31][32][33][34]. In either case the volatile organic components are entrained and carried along with the steam at a rate proportional to their relative partial pressure and molecular weight at the temperature of the distillation.…”

Determination of low-molecular-weight amines and ammonium in saline waters by ion chromatography after their extraction by steam distillation

“…Also, this technique was used to isolate volatile organic compounds, including amines, from process waters generated during the retorting of oil shale. After separation, the amines were determined by GC using a nitrogen/phosphorus or a flame ionization detector .…”