Abstract: The procedure of De Simoni et al. (2005) decouples the calculation of chemical speciation from the solution of solute transport in reactive transport models. It can be used to make numerical models faster and easier to develop as well as to deduce analytical and semi-analytical models. The disadvantage is that it is limited to chemical systems that only contain equilibrium aqueous and/or mineral reactions, with each mineral compulsorily present in the whole domain. Nevertheless, the procedure can be extended to include other processes as well. The talk presents three such extensions. The first is related to CO2 injection in saline calcareous aquifers, the second includes kinetically controlled organic carbon oxidation by various electron acceptors and the third adds heat transport. Besides being useful for decoupling chemistry in analytical/numerical reactive transport models, these extensions may give a deeper understanding of reactive transport and reveal interesting phenomena.