Effect of carbon adsorbent surface properties on the uptake and solvent regeneration of phenol

Journal Article · Thu May 01 04:00:00 EDT 1997 · Industrial and Engineering Chemistry Research

DOI:https://doi.org/10.1021/ie960545v· OSTI ID:509354

Kilduff, J E; King, C J ^[1]

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1. Univ. of California, Berkeley, CA (United States). Dept. of Chemical Engineering

Aqueous waste streams from petroleum refining, coal processing, and steel industries often contain phenolic compounds at concentrations of the order of 5,000 ppm. An investigation was made of the effects of surface properties on the uptake of phenol by carbonaceous adsorbents and on subsequent regeneration by acetone leaching. As-received carbons derived from different source materials were evaluated at pH values 2 and 9, and the surface properties of selected absorbents were varied by surface oxidation with concentrated HNO{sub 3} and/or heat treatment under nitrogen. Carbons derived from different source materials exhibited similar total uptake and reversible (acetone extractable) uptake at pH 2 but exhibited a wide range of reversibility at pH 9, conditions that promote oxidative coupling reactions. Surface acidity was investigated as a factor contributing to the reversibility of as-received carbons, and surface oxidation was evaluated as a means of improving regenerability. Oxidation of coal- and wood-based adsorbents with concentrated HNO{sub 3} increased surface acidity as measured by Boehm titration techniques and reduced the uptake of phenol but increased the reversible uptake. Reversibility was found to correlate with total acidity, reaching an upper plateau at a surface acidity of about 1 {micro}equiv/m{sup 2}. Uptake of water vapor by surface-treated carbons correlated with surface acidity, suggesting that selectivity for water may contribute to the suppression of oxidative coupling reactions.

• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 509354
• Journal Information: Industrial and Engineering Chemistry Research, Journal Name: Industrial and Engineering Chemistry Research Journal Issue: 5 Vol. 36; ISSN 0888-5885; ISSN IECRED
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
02 PETROLEUM
32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
ADSORBENTS
CARBONACEOUS MATERIALS
COAL INDUSTRY
METAL INDUSTRY
PETROLEUM REFINERIES
PHENOL
REGENERATION
SURFACE PROPERTIES