Wet oxidation of an azo dye: Lumped kinetics in batch and mixed flow reactors

Journal Article · Wed Dec 01 04:00:00 EST 1999 · AIChE Journal (American Institute of Chemical Engineers)

DOI:https://doi.org/10.1002/aic.690451213· OSTI ID:20006396

Donlagic, J; Levec, J

Oxidation of a dilute aqueous solution of a model azo dye pollutant (Orange II) was studied in batch and continuous well-mixed (CSTR) reactors. Both reactors operate at 200--250 C, and total pressures up to 50 bar and at oxygen partial pressure from 10 to 30 bar. The model pollutant concentrations were in a range between 100 and 1,000 mg/L, which may be found in industrial wastewaters. The dye oxidation undergoes parallel-consecutive reaction pathways, in which it first decomposes thermally and oxidatively to aromatic intermediates and via organic acids to the final product carbon dioxide. To develop a kinetic equation capable of predicting organic carbon reduction, all organic species present in solution were lumped by total organic carbon (TOC). The lumped oxidation rate in batch reactor exhibited second-order behavior, whereas in the CSTR is was found linearly proportional to its TOC concentration. The lump behavior in batch reactor was dominated by the refractory low molecular mass aliphatic acids formed during the oxidation.

• Research Organization: National Inst. of Chemistry, Ljubljana (SI)
• OSTI ID: 20006396
• Journal Information: AIChE Journal (American Institute of Chemical Engineers), Journal Name: AIChE Journal (American Institute of Chemical Engineers) Journal Issue: 12 Vol. 45; ISSN AICEAC; ISSN 0001-1541
• Country of Publication: United States
• Language: English

Related Subjects

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
AZO DYES
CHEMICAL REACTION KINETICS
INDUSTRIAL WASTES
OXIDATION
WASTE WATER
WATER TREATMENT