It is crucial to develop an effective and easily recoverable phosphate absorbent for the control of eutrophication problems in polluted rivers. In this study, a stable particulate adsorbent with a diameter of 5 mm synthesized from lanthanum, activated carbon, and zeolite (La-CZ) was developed, characterized, and tested for the removal of phosphate from wastewater in a small-scale reactor, which was designed to easily recycle La-CZ with a basket. Batch studies showed that La-CZ could reach adsorption equilibrium within 2 h and the maximum phosphate sorption capacity was 18.2 mg g−1
. The experimental data showed good compliance with the Langmuir isotherm model and pseudo-second-order kinetic model, implying that chemisorption dominates the phosphate uptake process. La-CZ exhibited a stable adsorption capacity over a wide pH range (3–7), while the adsorption capacity decreased slightly under alkaline conditions. Although Nitrates (NO3−
) and Carbonate (CO32−
) had some effects, normal coexisting ions such as Chloride (Cl−
), Sulfate (SO42−
), and Fluorine (F−
) had no significant effects on the phosphate adsorption capacity of La-CZ. The main form of phosphate removed from the reaction system was HCl-P (77.68%), as determined through phosphorus fractionation. In particular, this study designed a replaceable filler-type reactor integrating a reflux and aeration system, 98.8% of phosphorus could be removed from actual wastewater, and La-CZ could be reclaimed easily. This work provides an excellent reference for particulate adsorbents that can efficiently remove phosphate in practical applications in the future.
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