Processes Of Chemical Liberation, Recovery Or Purification Of Natural Cellulose Or Fibrous Material Patents (Class 162/1)
- Treatment of ground-wood or sawdust (Class 162/71)
- Organic (Class 162/72)
- Per-compound (e.g., peroxide, perborate) (Class 162/78)
- Heavy metal or aluminum containing (Class 162/79)
- Phosphorus, boron or silicon containing (Class 162/80)
- Nitrogen oxide, acid, or salt thereof (Class 162/81)
- Sulfur containing (Class 162/82)
- Chlorine containing (Class 162/87)
- Alkali metal, ammonium, alkaline earth metal or magnesium hydroxide or carbonate (Class 162/90)