Extraction of phenols from coal conversion process condensate waters. [MS thesis]

Technical Report · Fri Jun 01 04:00:00 EDT 1979

OSTI ID:5983283

Greminger, D C; King, C J

Condensate water samples from two typical coal-conversion processes were analyzed for phenols by gas chromatography-mass spectrometry and high-performance liquid chromatography. Significant amounts of phenol, dihydroxybenzenes and the trihydroxybenzene phloroglucinol were found. The presence of a trihydroxybenzene is particularly important as trihydroxybenzenes are extremely resistant to biological oxidation. The effects of water-phase pH on the extraction equilibria of the weakly acidic phenols were studied in a series of pH-controlled batch extractions of phenol, resorcinol, and hydroquinone into diisopropyl ether (DIPE) and hydroquinone into methyl isobutyl ketone (MIBK). The equilibrium distribution coefficient K/sub D/ decreased sharply in the pH range typical of condensate waters, 8.7-9.8, which is also the range of the pK/sub a/'s of the phenols. A simple model combining the acid ionization and the phase distribution equilibria fit the data well. Batch extractions of di- and trihydroxybenzenes into MIBK and DIPE showed MIBK to be clearly a better solvent than DIPE. The distribution coefficients in MIBK were an order of magnitude greater than those in DIPE, some of which were much less than unity. DIPE is currently used in the Phenosolvan process to extract phenol from coke-oven and coal-conversion effluent waters. With the K/sub D/'s measured in this work, calculations showed that the Phenosolvan process, as currently run, will not remove polyhydroxybenzenes from alkaline water solution to the levels required for further treatment, recycle or discharge of the condensate waters.

• Research Organization: California Univ., Berkeley (USA). Lawrence Berkeley Lab.
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 5983283
• Report Number(s): LBL-9177
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010404* -- Coal
Lignite
& Peat-- Gasification
010800 -- Coal
Lignite
& Peat-- Waste Management
AROMATICS
CHEMICAL ANALYSIS
CHROMATOGRAPHY
COAL GASIFICATION PLANTS
DEVELOPERS
ETHERS
EXTRACTION
GAS CHROMATOGRAPHY
HYDROGEN COMPOUNDS
HYDROXY COMPOUNDS
INDUSTRIAL PLANTS
ISOPROPYL ETHER
KETONES
LIQUID WASTES
MASS SPECTROSCOPY
METHYL ISOBUTYL KETONE
ORGANIC COMPOUNDS
ORGANIC OXYGEN COMPOUNDS
OXYGEN COMPOUNDS
PH VALUE
PHENOLS
POLYPHENOLS
RESORCINOL
SEPARATION PROCESSES
SOLVENT EXTRACTION
SOLVENT PROPERTIES
SPECTROSCOPY
WASTE WATER
WASTES
WATER