Patent ID: 8231856

Claim:
A method of preparing pharmaceutically acceptable sodium chlorite comprising: (i) concentrating a sodium chlorite solution to precipitate impurities and form a concentrated sodium chlorite solution and precipitated impurities; (ii) removing said precipitated impurities from said concentrated sodium chlorite solution; (iii) cooling said concentrated sodium chlorite solution to induce crystals to separate from said concentrated sodium chlorite solution; and (iv) harvesting said crystals to yield pharmaceutically acceptable sodium chlorite; wherein said pharmaceutically acceptable sodium chlorite contains an amount of chlorate ion, wherein said amount of chlorate ion is less than about 1.5% by weight, or wherein said pharmaceutically acceptable sodium chlorite contains an amount of sulfate ion, wherein said amount of sulfate ion is less than about 0.7% by weight, or wherein said pharmaceutically acceptable sodium chlorite contains an amount of chloride ion, wherein said amount of chloride ion is less than about 1.9% by weight.