摘要：To study the interaction between phosphorus and selenium (IV ) on the surface of biochar, the effects of three concentrations of phosphorus and selenium (IV ) were studied using batch experiments. The results indicated that under a selenium gradient of 8.5-11.5 (ig.L"1, different concentrations of phosphorus solutions could promote and inhibit the adsorption of selenium on biochar. A t an initial selenium concentration of 11, 10.5, and 10 g.L"1, the effect of 30, 300, and 3000 g.L"1 concentrations of phosphorus on the adsorption of selenium on biochar changed from promotion to inhibition. The interaction effect of 3000 g.L"1 phosphorus concentration on the adsorption of selenium on biochar was the most obvious, with the highest effect of 3% promotion and 3.1% inhibition. Under the selenium gradient of 85-115 g.L-1, the selenium adsorption capacity of biochar decreased by 0.42%, 1.89%, and 2.61% at phosphorous concentrations of 30, 300, and 3000 pg.L-1, respectively. The inhibitory effect was not conspicuous at the concentration of 30 (ig.L-1 but became increasingly notable with the increase in phosphorus concentration. Under a selenium gradient of 850-1150 (ig.L-1, the different phosphorus concentrations showed no significant effect on the adsorption of selenium on biochar after inhibition. The higher the phosphorus concentration was, the more notable the inhibition. The phosphorus solutions of 30, 300, and 3000 g.L-1 reduced the adsorption of selenium on biochar by 1.9%, 3.23%, and 3.40%, respectively. The results showed that the different phosphorus concentrations promoted the adsorption of selenium on biochar at lower selenium concentrations. When selenium concentration increased, the adsorption of selenium was gradually inhibited, and the inhibition gradually disappeared with an increase in selenium concentration. The effect of phosphorus on the adsorption of selenium on the biochar is mainly physical.
