Adsorption Isotherms and Hysteresis of Proton Adsorp- Tion by Goethite
نویسندگان
چکیده
Madrid, L. and De Arambarri, P., 1978. Adsorption isotherms and hysteresis of proton adsorption by goethite. Geoderma, 21: 199-208. The adsorption of H+ions by goethite is only partially reversible and the adsorption process is faster than desorption. The adsorptian isotherm shows two inflexion points at pH y,alues 7.5 and 9.5, which can be attributed to the existence of two ar more types of OH groups on the surface with different basic strengths. The lack of reversibility is attributed to partíal alterations of the surface by rearrangement of surface atoms although contributions of other phenomena to the overall process cannot be excluded.
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