Hydrogen peroxide with sodium silicate at >60C or Thiourea dioxide and sodium hydrosulfite might also be useful.

According to my little knowledge, sodium hypochlorite (NaClO) is suitable for bleaching many items including the natural fibers of cellulose. It is available in most countries. Hydrogen peroxide is a good bleach but it needs high temperature to whiten "this requires due care".

Sometimes, chemists may combine 2 bleaches on a substrate but please try with small amounts on little fibers with precautions "in the hood". If this works, then one can proceed. Wishing you success.

Thank you so much Dr. Nizar

Hydrogen peroxide with sodium silicate at >60C or Thiourea dioxide and sodium hydrosulfite might also be useful.

Thank you so much Dr.Amin for your answer