Alginate or alginic acid is the other natural marine polymer with plenty of applications. The polymer is an anionic polysaccharide refined from brown seaweed and possesses a remarkable property to absorb water quickly and efficiently. Alginate is widely used in foods and beverages to make foams, gels and stable solutions, without introducing an industrial chemical. It is also used in textile and paper manufacturing, in biological and chemical encapsulation and in water treatment and research studies. Alginate is also produced by some bacterias. Bacterial Alginate is suitable in pharmaceutical and medical applications.

In water treatment Alginate is frequently used as a flocculant where it in some cases can substitute synthetic polymers based on acrylamide. The idea is that the alginate binds different particles together in stringer aggregates, making them easier to remove from the water.

 

Alginate2

The structure of alginate