Although conventional chemical-based coagulants such as aluminum and iron (III) salts are effective in wastewater clarification,there are several drawbacks associated with their usage suchas ineffectiveness in low-temperature, adverse effects on humanhealth, production of large sludge volumes and change in pH ofthe treated water.
To solve theseproblems, natural coagulants extracted from plants have beenintroduced (Vieira et al., 2010). Plant-based coagulants includepolysaccharides and proteins. Polysaccharides are a family of car-bohydrates made of sugar rings linked by glycosidic bonds andvarious side functions. When charges are present, polysaccharidesbehave as polyelectrolytes. The negatively charged groups are car-boxylic groups or sulfate groups and positively charged groups areammonium