Sawdust contains 50 to 60% cellulose and about 30% lignin. Cellulose is an important component in animal feeds as a source of energy while lignin acts as a barrier to the digestibility of cellulose. Thus, the animals can hardly digest the sawdust. The lignin can be removed or reduced by first treating the sawdust before it is fed to the animals.
* Sawdust, nitric acid, sodium hydroxide
Equipment: Mixing vessel, Drier
1. Step the sawdust in 5% nitric acid solution (V/V) at a ratio of one part sawdust to 10 parts nitric acid for one hour at 80 C.
2. Wash the nitrated sawdust with water.
3. Soak the sawdust in a 5% sodium hydroxide solution for one hour. (To make 5% sodium hydroxide solution, dissolve 50 gms. sodium hydroxide, technical grade, in one liter of water).
4. Thoroughly wash the sawdust and then air-dry.
Source: Technology developed by: FPRDI (DOST)