Characteristics of diethylenetriamine-crosslinked cotton stalk/wheat stalk and their biosorption capacities for phosphate

► We prepare two biosorbents by epichlorohydrin-diethylenetriamine-trimethylamine method from cotton stalk and wheat stalk. ► Contents of holocellulose in raw materials correspond to the distinction of phosphate adsorption capacities between different biosorbents. ► We validate the ion exchange mechanism by Raman spectrum and regeneration tests. ► Effect of pH on adsorption of phosphate and their potential mechanism were discussed by Raman spectrum.