'Green rust' intercalated with aromatic sulfonates can potentially be effective materials for the treatment of soil and groundwater polluted with chlorinated benzenes. We investigated the potential intercalation of benzene sulfonate (BzS) and 1,3-benzene disulfonate (BzDS) into green rust sulfate (GR _SO4 ) via ion exchange. The GR _SO4 reacted with various concentrations of sulfonates were characterized by X-ray diffraction, X-ray scattering and transmission electron microscopy. GR interacted with BzDS did not result in intercalation due to stearic hindrance and electrostatic repulsion. For BzS, mixtures of GR _SO4 and GR-BzS (d ₀₀₁ = 14.3 Å) were obtained at molar equivalents of ion exchange capacity >5. The intercalation of BzS in the GR structure is limited (~18% intercalation) since BzS cannot fully replace SO ₄ ^2- . The BzS molecules are likely arranged in the interlayer as a dehydrated monolayer with the -SO ₃ groups facing away in alternate directions.