Limited-penetration probes for surface sites of coal. Eighth quarterly report, June 1-August 31, 1984. [3,5-di-t-butylphenol]
The purpose of this project is to develop methods of measuring the concentrations and strengths of acidic and basic surface sites on coal powders. We started out by measuring the adsorption onto powdered coal of organic acids and bases from iso-octane but soon found that these acids and bases penetrated into the coal and measured bulk sites in addition to surface sites. During this period we applied some of the findings of Larsen (at Lehigh) and of Aida, Squires and Hansen (at Iowa State) by using t-butyl derivatives of organic acids and bases to interact only with surface sites and not to penetrate into the coal and interact only with bulk sites. These acidic and basic test probes are now referred to as limited-penetration probes. Flow microcalorimetric adsorption exotherms and desorption endotherms for iso-octane solutions of 3,5-di-t-butylphenol versus phenol as they are pumped through a hundred-milligram bed of low-ash anthracite powder (PSOC-870) were made and compared. In the case of phenol the initial exotherm is larger than the other exotherms and larger than the endotherms; this is evidence that phenol penetrates into the bulk phase of the coal where it senses more basic sites and is less accessible for desorption. The flow desorption is shown in the uv trace of the desorbing phenol which is seen to take a long time to return to the base-line. 3 figures.
- Research Organization:
- Lehigh Univ., Bethlehem, PA (USA). Dept. of Chemistry
- DOE Contract Number:
- FG22-82PC50809
- OSTI ID:
- 6207162
- Report Number(s):
- DOE/PC/50809-T8; ON: DE85004804
- Resource Relation:
- Other Information: Portions are illegible in microfiche products
- Country of Publication:
- United States
- Language:
- English
Similar Records
(Sorptive properties of coal fines). Tenth quarterly report, December 1, 1984-February 28, 1985
Methods for characterizing the acidic and basic surface sites of coal
Related Subjects
ANTHRACITE
SORPTIVE PROPERTIES
COAL FINES
PHENOL
ADSORPTION
DESORPTION
PHENOLS
ADSORPTION HEAT
CALORIMETRY
EXPERIMENTAL DATA
OCTANE
PROBES
RESEARCH PROGRAMS
ALKANES
AROMATICS
BLACK COAL
CARBONACEOUS MATERIALS
COAL
DATA
ENERGY SOURCES
ENTHALPY
FOSSIL FUELS
FUELS
HYDROCARBONS
HYDROXY COMPOUNDS
INFORMATION
MATERIALS
NUMERICAL DATA
ORGANIC COMPOUNDS
PHYSICAL PROPERTIES
SORPTION
SURFACE PROPERTIES
THERMODYNAMIC PROPERTIES
010600* - Coal
Lignite
& Peat- Properties & Composition