(cotton wool and microcrys-talline cellulose) that adsorbed SRDW under caustic conditions.
Chitosan, cotton wool, and microcrystalline cellulose
were able to remove SRDW to 96, 67, and 68% of SRDW,
respectively, at a system pH of 10 at an equilibrium time of
24 h. This indicated that hydroxyl groups were involved in
SRDW adsorption under caustic conditions.