Rare-earth　element-based　materials　have　attracted　extensive　interest　due　to　their　effectiveness　in　phosphate　removal.　However,　there　are　ongoing　challenges　related　to　enhancing　the　phosphate　adsorption　capacity　and　regenerating　the　lanthanum-based　adsorbents.　This　study　focused　on　the　preparation　of　La-Zr　bimetallic　modified　diatomite　composites　with　different　molar　ratios　using　a　simple　coprecipitation　method.　These　composites　were　employed　as　efficient　adsorbents　for　the　removal　of　low-concentration　phosphate.　After　conducting　a　preliminary　assessment　of　the　phosphate　adsorption　capacities　of　the　synthesized　La-Zr　bimetallic　modified　diatomite　composites,　the　composite　with　the　La/Zr　molar　ratio　of　1:1　(designated　as　La1Zr1-DE)　was　selected　for　further　characterization　and　evaluation.　The　maximum　phosphate　adsorption　capacity　of　La1Zr1-DE,　determined　using　the　Langmuir　isotherm　model,　was　found　to　be　116.2　mg　P/g.　The　adsorption　process　of　phosphate　by　La1Zr1-DE　can　be　primarily　attributed　to　mechanisms　such　as　ligand　exchange,　inner-sphere　complexation,　and　surface　precipitation.　Furthermore,　La1Zr1-DE　exhibited　excellent　selectivity　for　phosphate　and　demonstrated　good　regeneration　capabilities.　This　study　offers　a　comprehensive　exploration　of　the　adsorption　mechanisms,　providing　a　theoretical　basis　for　the　development　of　more　effective　and　sustainable　phosphate　adsorbents.　©　2025　Elsevier　B.V.