Joanna Lach, Ewa Okoniewska, Agnieszka Ociepa-Kubicka, Anna Szymonik
Politechnika Częstochowska
Abstract
The presented work is aimed at comparing two types of gaseous modification: conventional with the use of external source of energy (heat) and originally developed method with Joule heat generated during the flow of electrical current through a carbon bed. Conventional modification of ROW 08 Supra activated carbon was conducted in a rotary furnace in the atmosphere of (1) steam and carbon dioxide at temperature of 400 and 800°C and (2) air at the temperature of 400°C. The modification of activated carbon in the electric heating experimental system (referred to as SEOW) occurred in the process of heating of activated carbon during the flow of electric current through the carbon bed up to 400°C, followed by cooling down with the air or carbon dioxide. Both methods for modification of activated carbons allowed for increasing adsorption capacity towards ions Pb(II). The advantage of heating the activated carbon with the electric heating experimental system (SEOW) required far less energy than in case of conventional method (up to many fold).
In case of modified carbon ROW 08 Supra, the increased adsorption efficiency was obtained for coals modified at 800°C and the carbon modified at 400°C with the participation of water vapor. As a result of modification of the SEOW carbons for all analyzed activated carbons, the adsorption percentage increased. Among all the modified activated carbon, the highest adsorption capacity has been given to carbon modified to SEOW through heating it to 400°C and air cooling as well.
The results are described by the means of Freundlich and Langmuir isotherm. In order to determine the coefficients of Langmuir isotherm, five different rectilinear forms were used. Among the analyzed issues the best fit to the experimental results obtained for the I Langmuir isotherms (the highest values of the coefficients R2).
The impact of pH and temperature on the effectiveness within the adsorption solution of Pb (II) was also analyzed. The most effective adsorption of lead from solutions of pH 2, 4, and 6 occurred at the highest pH, but the differences between the adsorption solution at pH 6 and pH 8 has been low. Within the adsorption from solutions having a pH of 2 a very little adsorption of lead was observed. Furthermore the size of adsorption of solutions at 20, 30 and 40°C was analyzed as well. What has been found is that through increasing the temperature the efficiency of the adsorption process within Pb (II) is raised.
Słowa kluczowe:
adsorpcja, ołów, izoterma Langmuira
042. Adsorption of Lead on ROW 08 Supra Modified Activated Carbon
Keywords:
adsorption, lead, Langmuir isotherm
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Zadanie Czasopismo, Annual Set The Environment Protection Volume 17. Year 2015 (wersja elektroniczna) dofinansowane ze środków Ministerstwa Nauki i Szkolnictwa Wyższego
