ITEM	Specifications
Oxalic acid (as H2C2O4·2H2O)  %≥	99.6	99	96
Sulfate (as SO4)      %≤	0.07	0.10	0.20
ignition residue (650°C)	0.01	0.08	0.20
Heavy metals (as Pb)   %≤	0.0005	0.001	0.02
Iron (as Fe)	0.0005	0.0015	0.01
chloride  (as Cl)%≤	0.0005	0.002	0.01
calcium (as Ca) %≤	0.0005	0.002	0.01