The Experimental Study On The Removal Of Nitrogen And Phosphate With The Zeolite Modified By Lanthanum

With the improvement of standard of living and the development of economy, in lately years, the pollution of nitrogen and phosphate is more serious than before. The excessive nitrogen and phosphate will cause the water abundant in alimentation, and affect the environment. So how to control and decrease the concentration of nitride and phosphate in the wastewater and dispose of slightly polluted water has become the new task in the modern wastewater dispose field.This investigation used the lanthanum loaded on the nano-power , and the modified zeolite can adsorb ammoniac nitride and phosphate simultaneous, the capability of adsorption , the period of adsorbent, easy to recycle, used convenienceThe main content of the described as follows:(1)the zeiolite modified with lanthanum, the best concentration and pH value of modified solution, the time and temperature of modified process were studied (2) Study the Influential factors of nitride and phosphate removal, including: ,the variation of wastewater (such as pH range of the solution , the concentration of pollutant ) the dosage , the time and the interfere ions in solution .(3) determine the condition of recycle (4) do some primary analyse to the mechanism of modified and adsorption.The result of researches show that:(1) when the time of dipping was 16 hours , the pH value was 12, the ratio of zeolite and solution was 1:50 and the dry temperature was 100℃are the optimal condition of modified (2) when the concentration of ammnoia nitrogen and phosphate was 30 mg/L and 5 mg/L respectively, the optimal adsorb condition was :the dosage was 3g/L,pH value was 5 and the time of adsorbed was greater than or equal to 30 minutes.(3) the phosphate in solution not has obvious influence to the removal of ammnoia nitrogen, however, the ammnoia nitrogen can promote the adsorbent to adsorbed the phosphate ,the kalium ion and nitrate nitrogen not has obvious influence to the removal of ammnoia nitrogen and phosphate, the ion of calcium inhibiting the removal of ammnoia nitrogen, but promoting the removal of phosphate , the ion of fluorine not has obvious influence to the removal of ammnoia nitrogen, has competitive efect with phosphate. (4) the reclaim solution was alkalinity, the optimal effect can be reached when the concentration of reclaim solution was 0.15mol/L and the time was 4 hours.(5) do some primary analyse to the mechanism of modified and adsorption, the main reason of the modified material can adsorb the ammnoia nitrogen was the nano-zeolite has the capability of ions exchange, the active site to removal phosphate is the rare earth oxide doped on the nano-zeolite.(6)after the measuring and fitting, the adsorption isotherm of ammnoia nitrogen was correspond with the model of Langmuir, the adsorption isotherm of phosphate was correspond with the model of muti-layer.