Further Advances Extended Triple-Layer Model

3 Further Advances Extended Triple-Layer Model 

Recently, the extended triple layer model (ETLM) was introduced by Sveijensky and coworkers (Sverjensky 2005 Sveijensky and Fukushi 2006), incorporating prediction of intrinsic equilibrium constants based on crystal chemical, electrostatic, and thermodynamic theory, allowing the reduction of adjustable parameters. In the ETLM, proton sorption Reactions 12.2 and 12.3 are written as associations  

The thermodynamic equilibrium constants are related to the point of zero net proton charge (pznpc) (Section 5.5) by 

In the first stage, Reaction 12.28, the surface is protonated, and the anion adsorbs in the 1 plane as outer sphere complex, losing two protons the protons cancel out but are retained here to remark the interface planes involved, which define the contributions to the electrostatic work. In Reaction 12.29, the anion binds specifically, and two water molecnles are removed from the 0 plane becanse water has a dipolar moment, there is an electrostatic work involved, which is not considered in the original TLM. The electrostatic factor involved in Reaction 12.28 results from H2ASOJ adsorbing at the 1 plane, two protons adsorbing at the 0 plane, and two other protons desorbing from the 1 plane  

In the case of Reaction 12.29, the molar electrostatic work released by the desorption of n water molecules from the 0 plane is given, according to Sverjensky and Fukushi (2006), by 

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