Newsprint recycling gives rise to significant volumes of waste sludge which can be de-watered and combusted for energy-recovery. The residual combustion ash, whose primary crystalline constituents are; gehlenite (Ca 2 Al 2 SiO 7 ), åkermanite (Ca 2 MgSi 2 O 7 ), β-dicalcium silicate (Ca 2 SiO 4 ) and anorthite (CaAl 2 Si 2 O 8 ), is currently consigned to landfill disposal. It is demonstrated herein that a mixed product of Al-substituted 11 Å tobermorite (Ca 5 Si 6 O 18 H 2 ·4H 2 O) and katoite (Ca 3 Al 2 SiO 12 H 8 ) can be synthesised from newsprint recycling combustion ash via a hydrothermal route. Batch sorption studies confirm that this mixed product is an effective sorbent for the exclusion of Co 2+ and Sr 2+ from acidic aqueous media. Kinetic sorption data are analysed in accordance with the pseudo-first- and pseudo-second-order models, and steady-state data is fitted to the Langmuir and Freundlich isotherms. The Langmuir and pseudo-second-order models are found to provide the most appropriate descriptions of the sorption processes. The maximum uptake capacities for Co 2+ and Sr 2+ at 20 °C are 10.47 and 1.52 mgg −1 , respectively, and the respective apparent pseudo-second-order rate constants are estimated to be 5.08×10 −3 and 6.96×10 −3 gmg −1 min −1 .