90%:

外观Appearance                                     无色至黄棕色结晶
红外光谱鉴别Infrared spectrometry       符合
纯度Purity                                              ≥90% (中和滴定)
磺酸sulfuric acid(H2SO4)                        <10%

98%，无水:

外观Appearance                                   White to Faintly Beige Power or Lumps
红外光谱鉴别Infrared spectrum           Conforms to Structure
纯度Purity (Titration by NaOH)             ≥98.0 %
熔点Melting point                                  57°C-61°C
纯度Purity (HPLC)                                 ≥98.0 %
水分Water (by Karl Fischer)                   ≤1.0 %
灼烧残渣Residue on ignition (Ash)         ≤0.2 %
硫酸根SO4                                           ≤600 ppm