Abstract
The present investigation concerns with an apllication of the automatic recording liquid chromatography with thermal detection to the adsorption measurement. The adsorption of hydrochloric acid on polyamide powder was measured isothermally at 30°C, 40°C and 50°C. Polyamide powder was packed in two columns with thermo couple and put into double thermostat. Firstly, distilled water was flowed in at the constant flow rate in order to stabilize the thermo couple, then hydrochloric acid was flowed. The heat of adsorption around the thermo couple was recorded as change in temperature and the total variation (peak areas=Hw) was observed. The pH-Hw isotherm was almost agreed to the adsorption isotherm of hydrochloric acid on polyamide and these isotherms were in good agreement with the Langmuir's adsorption isotherm between pH4.30 to pH2.50. From these pH-Hw isotherms, the standard abilities and standard heat of adsorption were obtained. These values [ex. -Δμ°=10.2kcal/mol (40°C), -ΔH=12.0kcal/mol] were essentially identical to values from adsorption isotherm and other reports. From a consideration of these results, it seems most reasonable to conclude that the automatic recording of liquid chromatography with thermal detection is useful to measurement of adsorption.
