Glyphosate adsorption on synthetic allophanes and halloysite: Effects of pH and mineral properties

Background Glyphosate (GLP) is a widely used herbicide with possible adverse effects on human health and the environment. In soils, GLP strongly adsorbs clay-sized minerals, depending pH, amount of organic carbon, as well contents properties Al Fe oxyhydroxides clay minerals. Many minerals have already been investigated regarding adsorption behavior, but information commonly found in volcanic soils still lacking. Aim The aim this study was to investigate for first time pH-dependent allophane halloysite, typical soils. Methods studied batch experiments at three pH values (5, 6, 7). Synthetic allophanes two different initial Al:Si ratios (1.4 1.8) halloysite were adsorbents. Results capacity (AC) increased rising ratio decreasing pH. AC significantly higher than that halloysite. larger reported other oxyhydroxides, especially low most Conclusion Different mineral formation pathways notably versus allophanes, affect soils’ retention GLP. high may induce mobility allophane-containing Long-term use accumulate these potential biodiversity ecosystem services.