Removal of phosphorus from water using lignocellulosic material modified with iron species from acid mine drainage

Lignocellulosic biosorbents, including juniper fiber, show promise as sorbents for removing pollutants from wastewater run-off because of their low cost. In this study, juniper fiber modified with iron species from acid mine drainage (AMD) was tested for its capacity to remove phosphorus from water compared to unmodified juniper fiber. In batch tests, the maximum adsorbate loading (Qmax) of phosphorus onto the modified adsorbent was 1.83 mg g(-1) at pH 4.0, obtained by fitting the isotherm results to the Langmuir isotherm model. This value is similar to the sorption capacity of other conventional adsorbents such as goethite, which implies that the modified lignocellulosic material would be effective as a sorbent for removing phosphorus from water. In the kinetic test, the pseudo-second order kinetic model fitted well the sorption of phosphorus onto the modified filter medium, showing the kinetic constant (k) of 8.09 x 10(-2) g(mg min)(-1) at initial phosphorus concentration of 10 mg l(-1).