Required Cards:

SORPTION

Opens the sorption reaction block.

Optional Cards:

ION_EXCHANGE_RXN

Sorption defined through ion exchange reactions

ISOTHERM_REACTIONS

Sorption reactions defined by isotherms (e.g. linear, Langmuir, Freundlich)

SURFACE_COMPLEXATION_RXN

Opens surface complexation reaction block.

Examples

SORPTION
  ISOTHERM_REACTIONS
    Tracer
      DISTRIBUTION_COEFFICIENT 0.25d3
    /
    Tracer2
      DISTRIBUTION_COEFFICIENT 0.5d3
      FREUNDLICH_N 1.67  ! 1/n = 0.6
    /
  /
  SURFACE_COMPLEXATION_RXN
    EQUILIBRIUM
    MINERAL Kaolinite
    SITE >FeOH 0.00636
    COMPLEXES
      >FeOHUO3
      >FeOHUO2++
    /
  /
  ION_EXCHANGE_RXN
    MINERAL Calcite
    CEC 1.e-1
    CATIONS
      Ca++ 1.e-4
      Na+   1.d0
    /
  /
END