| abstract |
The invention relates to a water purification method and composition useful for removal of trace quantities of harmful heavy-metal contaminants like Arsenic, in addition to removal of micro-organisms like viruses, bacteria and cysts to make the water suitable for human consumption. It is an object of the present invention to provide a coagulant composition for purification of water that provides for removal of at least 90% Arsenic, and 6-log bacteria, 4-log virus and 2-log cysts from contaminated water, the composition comprising: n(i) 5 to 30 wt% Aluminium salt, n(ii) 1 to 10 wt% Iron salt and, n(iii) 0.2 to 5 wt% KMnO 4 , wherein the ratio of the Al-ions to the Fe-ions to the KMnO 4 is in the range of 1:0.2:0.2 to 1:2:2. nThe Aluminium salt is selected from Aluminium sulphate, Aluminium chloride, Polyaluminium chloride, Polyaluminium sulphate or Aluminium chlorohydrate and the Iron salt is selected from Ferrous sulphate, Ferric sulphate, Ferrous chloride or Ferric chloride. |