Regeneration of alkali in caustic desulfurization systems: Quarterly report, 1 January 1988--31 March 1988

Technical Report · Sun May 01 04:00:00 EDT 1988

OSTI ID:6694713

Markuszewski, R; Norton, G A; Chriswell, C D

Additional studies were performed on model spent acid solutions to determine the effects of time, temperature, and pH on yields of natrojarosite (NaFe/sub 3/(SO/sub 4/)/sub 2/(OH)/sub 6/). The desired pH values (in the range of 1.1 to 2.3) were maintained during the tests by adding either H/sub 2/SO/sub 4/ or CaCO/sub 3/. It was shown that precipitation of jarosite-type compounds can effectively remove Fe and SO/sub 4//sup =/ impurities from model solutions of spent acid. Although the analytical data for Na require further interpretation, it appears that substantial amounts of Na can also be precipitated as natrojarosite. The optimum pH for precipitating natrojarosite appears to be about 1.5. Using Fe/sub 2/O/sub 3/ as a source of ferric iron does not appear to be a satisfactory alternative to using Fe/sub 2/(SO/sub 4/)/sub 3/. If a NaOH/KOH mixture is used in the MCL process, the apparent preferential precipitation of Na/sub 2/CO/sub 3/ rather than K/sub 2/CO/sub 3/ could improve process economics slightly, but it may complicate precipitation of Na as natrojarosite from spent acid streams since the Na jarosite species does not form as readily as the K jarosite. 6 refs., 6 figs., 5 tabs.

• Research Organization: Ames Lab., IA (USA)
• DOE Contract Number: W-7405-ENG-82
• OSTI ID: 6694713
• Report Number(s): IS-4961; ON: DE89003757
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010300* -- Coal
Lignite
& Peat-- Preparation-- (1987-)
ALKALI METALS
ALKALINE EARTH METAL COMPOUNDS
CALCIUM CARBONATES
CALCIUM COMPOUNDS
CALCIUM SULFATES
CARBON COMPOUNDS
CARBONACEOUS MATERIALS
CARBONATES
CLEANING
COAL
DOCUMENT TYPES
ECONOMICS
ELEMENTS
ENERGY SOURCES
FOSSIL FUELS
FUELS
GYPSUM
HYDROGEN COMPOUNDS
HYDROXIDES
IRON
MATERIALS
METALS
MINERALS
NONMETALS
OXYGEN COMPOUNDS
PH VALUE
PRECIPITATION
PROGRESS REPORT
REGENERATION
REMOVAL
SEPARATION PROCESSES
SODIUM
SULFATE MINERALS
SULFATES
SULFUR
SULFUR COMPOUNDS
TEMPERATURE EFFECTS
TRANSITION ELEMENTS
WASHING
YIELDS