MnO₂Oxidative Degradation Of Glyphosate Catalyzed By Electrochemical Process

Glyphosate is a highly efficient, low toxicity, inner-absorption, abroad spectrum of organicphosphorus pesticides, used worldwide. The degradation products of using glyphosate in theenvironment or in the process are harmful to the environment, posing a serious threat to people’snormal life. Domestic and foreign to glyphosate removal were studied, based on the existingdegradation, we propose the use of electrochemical catalytic MnO₂oxidation degradation ofglyphosate, using MnO₂and electrocatalysis MnO₂of glyphosate in water through a series ofprocessing experiment to energy saving and environmental protection of the dual effect, thespecific executive content as follows:1、MnO₂using alone the adsorption and oxidation of glyphosate, can achieve certain effects.This paper studies the glyphosate on surface of MnO₂adsorption-oxidation behavior,investigates the glyphosate concentrations, MnO₂dosage, reaction system of pH and co-existingcations on MnO₂adsorption-oxidation of glyphosate process effects, a preliminary analysis ofglyphosate degradation products. Research results show that, MnO₂dosage is bigger, the initialconcentration of glyphosate glyphosate lower removal rate is higher; acidic conditions arefavorable for MnO₂to glyphosate removal; the coexistence of Cu （II） on MnO₂to weeding sweetphosphine has obvious inhibitory effect on MnO₂adsorption-oxidation degradation ofglyphosate; main products are sarcosine, amino acid （glycine）, formic acid, acetic acid （glycolicacid） and PO43-.2、In the elec-catalytic MnO₂oxidation degradation of glyphosate study, examines thecurrent density, MnO₂dosage and the effect of initial pH system, the experimental results showthat, increasing the current density and increases the MnO₂dosage will increase the removal effect of glyphosate. pH effect of MnO₂surface electric properties, on the electrocatalytic effect,mainly reflected in the influence on MnO₂, alone had little effect on the electrochemical. Theelectrode plate and the MnO₂reaction and the characterization, preliminary analysis underconditions in which the products of degradation and hypothesized that the degradation pathway,obtained in the catalytic system, more thoroughly，products than pure MnO₂, more lasting effect.3、In this two system, glyphosate in a certain period of time can be effective degradation,degradation pathways in slightly distinction: in the separate MnO₂system, the product isdegraded into small molecular acids, ammonia nitrogen into the ultimate; and the electriccatalytic system, nitrogen is evident by the ammonia nitrogen continue to be oxidized to nitratenitrogen, at the same time in the catalytic system, and there are a few mineralized.MnO₂adsorption of glyphosate to electrostatic adsorption, the study results show that thegreater the MnO₂dosage, the initial glyphosate lower the concentration of glyphosate removalrate and the higher; acidic conditions favor of MnO₂on glyphosateremoved; coexistence of Cu（II） the MnO₂removal glyphosate significantly inhibited; of MnO₂adsorption-the oxidativedegradation of glyphosate product sarcosine, amino-acetic acid （Glycine）, acetic acid, glycolicacid （Glycolic Acid） PO43-. Electrochemistry involved in the MnO₂oxidation glyphosateexperiment, electrochemical degradation involved in which the oxidation of manganese ions andthe oxidation of the organic matter itself. The experimental data show that the electro-catalyticMnO₂oxidative degradation of glyphosate than removal of MnO₂on glyphosate alone is moreeffective and lasting.