ORCHESTRA:

• is a computer program for calculating chemical speciation and reactive transport processes.
• is written in Java and runs on Windows, Linux and Apple OSX.
• can be downloaded for free from this site.
• has a graphical user interface for quickly setting up  chemical equilibrium models.
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• has on-line example systems for batch and transport calculations
• comes with a large set of  adsorption models
• can be used to simulate equilibrium reactions , kinetically controlled reactions, radioactive decay, transport
• can create predominance / pe-pH diagrams:
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• allows users to construct new models by defining new model object classes and keywords.