*3.2.1.2 Acid-chlorite treatment (bleaching treatment)*

The acid-chlorite treatment is the partial or complete removal of lignin from lignocellulosic biomass by combined treatment with sodium chlorite acidified with glacial acetic acid. This process is commonly known as the bleaching or delignification process, which is performed by mixing distilled water, sodium chloride and acetic acid with lignocellulosic biomass at 70–80°C for 4–12 h. The blend is stirred overnight followed by washing with distilled water until neutral (pH = 7) is achieved. The white residual product characterized as holocellulose lignin-free is


## **Table 3.**

*Alkaline treatment of different lignocellulosic fibers.*


#### **Table 4.**

*Bleaching treatment of different lignocellulosic fibers.*

then collected and oven-dried. **Table 4** shows the varying conditions and reagents used by other researchers for bleaching treatment.
