Sorption on soil particulate organic matter

[peterwadeuk]

Greetings good persons,

I am modelling reactive transport through a soil column.

There is a significant proportion of organic matter in the soil.

I note the example "Example 19--Modeling Cd +2 Sorption With Linear, Freundlich, and Langmuir Isotherms, and With a Deterministic Distribution of Sorption Sites for Organic Matter, Clay Minerals, and Iron Oxyhydroxides". It seems that I need to retrieve sorption and exchange constants from literature. This is a very daunting prospect.

I need to model the retention of magnesium, calcium and iron, amongst other species.

Can anyone point me to a database that has already been developed, that models interaction of metals, including the alkaline earth metals, with solid organic matter?

All the best,
Peter

[dlparkhurst]

Here are a couple links into the literature. Ed Tipping created the computer program WHAM to model organic-metal binding. You can also look at the work of Gary Sposito and the program GEOCHEM.

[peterwadeuk]

Thank you David,

Please forgive low-level response.

I am unfamiliar with this interface and can't find the links you posted.

Could you please help?

I find some good information not only by Sposito but by people who refer to Sposito. Thank you for the advice.

Environ Toxicol Chem. 2006 Sep;25(9):2366-73: "The results suggested that Pb and Cu adsorption on POM was mainly through inner-sphere complexes with carboxyl and hydroxyl groups". This sounds promising because I could in principle use LFER to obtain the Langmuir constants for the less strongly bound alkaline earth metals.


Cheerio, Peter

[dlparkhurst]

I only intended to give you a couple of authors by which you could get a start on the literature.

[peterwadeuk]

Got it. Thought you meant hyperlinks :)