Natural polymers are unique materials due to inexpensive, easily available, reproducible
sources, hydrophilic and stable biopolymers, safe and devoid of side effects
and flexible polymers. In addition, they have excellent adsorption specifications to remove
pollutants including dyes from colored wastewater. Adsorption is a preferred method
compared to other methods due to its fast and comfortable and inscrutable to toxic contaminants.
The natural polymers also have excellent properties such as low initial cost,
production of nontoxic by-products, relatively simple design and productivity in time.
Properties of an ideal and suitable absorbent for removal dye include the following: extensive
surface, high capacity and ability to absorb, the pores with appropriate size and volume,
comfortable accessible, efficient, economical, high mechanical stability, compatibility,
easy regenerable, environmental friendly, high selectivity to elimination various dyes and needless of high
processing techniques. Therefore, researchers have lately centralized on expanding compounds based on natural
polymers. The current review provides information about the application of natural polymers as adsorbents
to remove dyes from colored wastewater. Also, some useful information about the influence of dye removal
process variables, dye adsorption mechanism, adsorption isotherms, kinetics, and thermodynamics are presented.