Adsorption of zinc on manganite (gamma-MnOOH): particle concentration effect and adsorption reversibility.
The adsorption and desorption processes of Zn(II) on gamma-MnOOH as a function of particle concentrations (Cp) were studied. An obvious Cp effect was observed in this adsorption system. The degree of adsorption hysteresis increased greatly with the increasing of Cp, indicating that the extent of the real metastable-equilibrium states deviating from the ideal equilibrium state was enhanced with the increasing of Cp. The Cp-reversibility relationship confirmed the metastable-equilibrium adsorption (MEA) inequality (Pan, 1998a), which was the core formulation of the MEA theory. Because the MEA inequality was based on the basic hypothesis of MEA theory that adsorption density [see symbol in text] is not a state variable, the Cp-reversibility relationship gave indirect evidence to the basic hypothesis of MEA theory.
Qin
Yan-wen
YW
State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
Pan
Gang
G
Zhang
Ming-ming
MM
Li
Xian-liang
XL
D000327:Adsorption; D017895:Manganese Compounds / Q000737:chemistry*; D008962:Models, Theoretical; D010316:Particle Size; D014873:Water Pollutants / Q000302:isolation & purification*; D018508:Water Purification / Q000379:methods; D015032:Zinc / Q000737:chemistry*
D017895:Manganese Compounds; D014873:Water Pollutants; C494384:manganite; D015032:Zinc