Highly effective wastewater phosphorus removal by phosphorus accumulating organism combined with magnetic sorbent MFC@La(OH)(3)

摘要

To enhance the efficiency of phosphate removal by phosphorus accumulating organisms (PAOs), a magnetic Fe3O4 core-shell (MFC) sorbent was synthesized to remove the intracellular phosphorus of PAOs. The MFC was prepared by the hydrothermal method, and then functionalized with La(OH)(3) by depositing on the MFC surface. The sorbent (MFC@ La(OH) 3) was easy to separate from wastewater and had a high phosphate adsorption capacity of 45.45 mg/g at 30 degrees C. The batch experiments were conducted to probe the influence of adsorbent on PAOs (Pseudomonas putida). The results showed that the adsorbent could inhibit the growth of microorganism by competing for the phosphate in solution, and further improving the hydrolysis of polyphosphates (polyP) from microorganism. The microorganism after the hydrolysis of polyP could accumulate phosphate more rapidly when it was added into phosphorus-rich medium. The optimized condition for polyP hydrolysis from microorganism was 0.1 g/100 mL of sorbent dosage and 1 h of contacting time. The sorbent exhibited stable phosphate adsorption behavior after 5 adsorption-desorption cycles. Phosphate could be effectively recovered through the regeneration of phosphate loaded MFC@ La(OH) 3 under alkaline condition. The present findings indicate that PAOs combined with MFC@ La(OH)(3) is a novel and highly effective method for removing phosphate in wastewater and recovering phosphorus resource.