Emission of Volatile Organic Compounds to the Atmosphere in the Solvent Sublation Process. II. Volatile Chlorinated Organic Compounds

Abstract

The mass of trichloroethylene, chlorobenzene, and 1,3-dichlorobenzene removed from an aqueous solution and emitted to the atmosphere during solvent sublation was determined experimentally. It was shown that the emission of these compounds in solvent sublation was reduced by 30 to 85% over air stripping under the same experimental conditions. The efficiency of removal of these compounds from water was also studied. The reduction of emissions over air stripping was more effective for the more hydrophobic and less volatile compounds. Emissions are reduced as the thickness of organic layer on the top of the column is increased. The use of decyl alcohol as the layer compound decreases emissions to a greater extent than does paraffin oil. Removal of these chlorinated volatile organic compounds from water by solvent sublation at an elevated temperature of 45°C is significantly faster than at room temperature. However, the emissions to the atmosphere are also increased.

A mathematical model and mechanism of sublation of dye-surfactant ion complexes

“…Karger [10] then qualitatively described the possible transport pathways in solvent sublation, for which two predominated transport processes existed: (1) transport within and on the surface of the bubbles, (2) a diffusive transport between the phases driven by a concentration gradient. Wilson et al then worked on building the mathematical models of the solvent sublation process [11,12,13]. However, their results have some discrepancy between the calculated and experimental results.…”

“…Most of these studies have focused on the removal of organic pollutants from aqueous systems, such as alkyl phthalate, volatile chlorinated organics, dichlorobenzenes, nitrophenols, polynuclear aromatics and chlorinated pesticides [5,6,7,8,9,10,11], and the emission of volatile organic compounds (volatile chlorinated organics and toluene) to the atmosphere in the solvent sublation [12,13]. Other studies concern the solvent sublation of dyes in aqueous solution, such as the separation of methyl orange from rhodamine B [14,15], the solvent sublation of bromophenol blue-hexadecyl pyridium chloride ion pair [16], magaenta (a cationic dye) with sodium lauryl sulfate [17] and direct red and acid red (two anionic dyes) with hexadecyltrimethylammonium ions [18,19].…”

The removal of humic acids from water by solvent sublation

“…Most of these studies have been focused on the removal of organic pollutants from aqueous systems, such as alkyl phthalate, volatile chlorinate organics, dichlorobenzenes, nitrophenols, polynuclear aromatics, and chlorinated pesticides [6][7][8][9][10][11], and the emission of volatile organic compounds (volatile chlorinated organics and toluene) to atmosphere in the solvent sublation [12,13]. Other studies are the solvent sublation of dyes in the aqueous solution, such as removal of bromophenol blue from water by solvent sublation with hexadecyl pyridium chloride into isopentanol [14,15], the separation of methyl orange from Rhodamine B [16], the solvent sublation of the methyl orange-hexadecyltrimethylammonium ion pair [17], Magenta (a cationic dye) with sodium lauryl sulfate [18], and Direct Red and Acid Red (two anionic dyes) with hexadecyltrimethylammonium ion [19,20].…”