| In this paper, the method of High Gas-stream Oxidation was introduced to regenerate Palygorskite adsorbent. The basic application research about adsorption-High Gas-stream Oxidation to treat dye wastewater was studied. The main research content and results were as follows:1. Adsorption behavior of methylene blue on Palygorskite was studied. Effects of particle size, pH, initial concentration of the dye's solution, temperature on adsorption are studied. The optimum adsorption conditions was composed of adsorption time 2h, initial pH and room temperature. A well fitted Langmuir equation was obtained for the adsorption isotherm within the observed temperature and the concentration of the dye's solution range, indicating an endothermic adsorption. Saturated adsorption capacity were 76.92mg/g, 84.03 mg/g, 86.96 mg/g respectively at temperature of 20℃, 30℃, 40℃. The kinetic study showed that the adsorption process could be described by the first-order rate expression of Lagergren and was under the control of external diffusion diffusion. The effect of flow rate on effluent quality was studied, and the result showed that the flow rate should be less than 5BV/h.2. Palygorskite adsorbed methylene blue was regenerated by high gas-stream oxidation oxidation. Effects of temperature, reaction time and the air flow rate on regeneration efficiency were studied. The higher the temperature, the more organic compounds would be oxidized and the regeneration efficiency would be higher. The larger the air flow rate, the regeneration efficiency would be higher. When the air flow rate increased to 1.5L/min, the regeneration efficiency changed little. The longer the regeneration time, the regeneration efficiency would be higher. When Palygorskite adsorbed methylene blue was regenerated over 15minutes, the regeneration efficiency changed little.3. The more regeneration times, the regeneration efficiency would slightly descend. From the thirteenth regeneration, the regeneration efficiency tended to be stable. Palygorskite was repeatedly used with steady performance.4. Methylene blue absorbed by Palygorskite lost crystal water below 100℃. It was pyrolyzed and carbonized from 100℃to 250℃and was oxidized by oxygen and converted to CO2,CO above 250℃and hydrocarbon from 300℃to 630℃. Nitrogen containing group in Methylene blue was oxidized forming NO. The regeneration process produced CO2, CO, NO2, NO, SO2 and hydrocarbon above 600℃. The regeneration was not thorough at 500℃. Methylene blue was nearly degraded completely from 600℃to 700℃.5. The optimum regenerative conditions were as following: temperature was from 600℃to 700℃, the reaction time was 10min and the air flow rate was 1L/min.
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