(1)Purity ≥ :85.0%
(2)Chroma ≤:10
(3)Residue on ignition%≤:0.1
(4)Volatilization acid£¨H£«£©/mmol/100g%≤: 0.02
(5)Chloride £¨Cl£©%≤ :0.0003
(6)Sulfate£¨SO4£©%≤ :0.003
(7)Nitrate (NO3)%≤ :0.0005
(8)Mn %≤ :0.0002
(9)Fe %≤ :0.002
(10)As %≤ :0.0001
(11)Heavy metal (Pb) %≤: 0.001