Removal of Phosphorus in Agricultural Run-off Water by Utilization of Lignocellulosic Biomass Filters : utilization of common reed as an adsorbent

Fertilizers used on agricultural farms contain a significant amount of phosphorus along with other nutrients, which are essential for crop growth. When it rains, phosphorus can be partially washed away from the farm, leaches into the surrounding ditching system and eventually ends up in lakes, seas, etc., which thus reduces the quality of the farming soil as well as contributes to the eutrophication phenomenon. The use of filters made from different types of lignocellulosic biomass modified with certain chemicals that can capture this nutrient before the run-off water reaches the ditching system would help solving this issue. In addition, this biomass and phosphorus containing filter material can be recycled back to the field to enhance the soil quality. Furthermore, the modification of biomass should be inexpensive and free from harmful chemicals. In this thesis, common reed, an abundant biomass in Finland, was first quaternizated with modifying chemicals, including urea, chlorocholine chloride and imidazole. After that, it was employed to test its phosphorus uptake capacity. From the results, it seems that common reed naturally releases an amount of phosphorus into the water. The use of chemicals to integrate this biomass seems to even increase the phosphorus concentration rather than mitigation. However, this could be due to the experimental errors, and since the number of the conducted experiments was not sufficient, proper conclusion cannot be made