Sorption of Cu2+ and Zn2+ ions by humic acids of tundra peat gley soils (Histic Reductaquic Cryosols)

Lodygin, E.D.

Автор: Lodygin E.D.
Журнал: Eurasian Soil Science
Том: 52
Номер: 7
Год издания: 2019
Издательство: Maik Nauka/Interperiodica Publishing
Местоположение издательства: Russian Federation
Первая страница: 769
Последняя страница: 777
DOI: 10.1134/S1064229319070093
Аннотация: Sorption properties of humic acid (HA) preparations extracted from the peaty horizon of peat gley tundra soil (Histic Reductaquic Cryosols) are characterized. The kinetic and thermodynamic sorption parameters of Cu2+ and Zn2+ ions by HAs are calculated. The sorption of the study heavy metal ions by HA preparations is estimated to be truly approximated by the pseudo-first-order response equation. The negative values of the Gibbs energy change at temperatures of 298.0 К and 314.3 К for Сu2+ (–26.2 and –24.5 kJ/mol, respectively) and Zn2+ ions (–22.2 and –22.0 kJ/mol, respectively) attest to the possibility of self-sorption of the study ions within the considered temperature range. Changes in the sorption enthalpy values (–33.1 kJ/mol for Cu2+ ions and –4.5 kJ/mol for Zn2+ ions) characterize both reactions as exothermal reactions. As the temperature rises, the sorption equilibrium constant for Сu2+ ions considerably decreases, whereas it does not change significantly for Zn2+ ions. The decreasing sorption equilibrium constants with the rise in temperature point to the equilibrium shift towards desorption. This is a characteristic feature of physical sorption that indicates possible existence of two fixation mechanisms of ions on the surface of HA preparations, namely, physical sorption and сhemisorption.
Добавил в систему: Лодыгин Евгений Дмитриевич

	ИСТИНА	Войти в систему Регистрация
	ИПМех РАН
	Главная Поиск Статистика О проекте Помощь

ИСТИНА

ИПМех РАН

Sorption of Cu2+ and Zn2+ ions by humic acids of tundra peat gley soils (Histic Reductaquic Cryosols)статья Исследовательская статья

Прикрепленные файлы