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研究了添加谷氨酸（Glu）对δ-MnO2吸附Cu2＋的影响。结果表明，Glu明显抑制了氧化锰对Cu2＋的吸附。最大吸附量从无Glu时的264．1mmol／kg降至有Glu存在时的179．2mmol／kg；并且吸附强度也有一定程度的降低。Glu的抑制作用在低pH（pH2．5～4．5左右）时最强，随pH值增高这种抑制作用逐渐减弱直至消失。造成Cu2＋吸附量降低的主要原因可能是：①吸附于δ-MnO2表面的Glu与氧化标发生还原反应脱去羧基，形成的惰性物质掩盖部分活性点位；②溶液中，络合能力较强的有机配体Glu与氧化标表面竞争溶液中的Cu2＋，使Cu2＋吸附量降低。
The effect of glutamic acid (Glu) on the adsorption of Cu2 + by δ-MnO2 was studied. The results showed that Glu significantly inhibited the adsorption of Cu2 + by manganese oxide. The maximum adsorption decreased from 264.1 mmol / kg in the absence of Glu to 179.2 mmol / kg in the presence of Glu; and the adsorption strength also decreased to a certain degree. Glu inhibition in the low pH (pH 2.5 ~ 4.5 or so) the strongest, with increasing pH value of this inhibition gradually weakened until disappear. The main reason for the decrease in the amount of Cu2 + adsorption may be as follows: ① Glu adsorbed on the surface of δ-MnO2 undergoes a reduction reaction with an oxidizing reagent to remove the carboxyl group, forming an inert substance to cover part of the active site; ② the solution has a strong complexation ability The organic ligand Glu competes with the target surface for Cu2 + in the solution to reduce the amount of Cu2 + adsorbed.