| Summary: | 碩士 === 嘉南藥理科技大學 === 環境工程與科學系碩士班 === 94 === Nitrate is one of main pollutants in the groundwater. Nitrate, indigested by the digested system, may be converted to nitrites, which could switch the iron in hemoglobin from ferrous to ferric state and make it no longer capable of carring oxygen. Nitrites can react with secondary amines to form N-nitrosamines, which are the well-known mutagen and carcinogen. In addition, the increase of nitrogen can enhance the eutrophication of the water body.
The aim of this study is to realize the removal efficiency and kinetics of nitrates in water treated by nanoscale Fe0/ Ni0. The influences of several factors, including pH, the adding ratio of Fe0 with Ni0, initial nitrate concentration and DO on the reaction of nitrates with nanoscale Fe0/ Ni0 would be operated by batch tests and to find the rate constants and half-life.
Results show that the removal efficiencies of nitrates in the low pH are all significant by adding no matter nanoscale Fe0, Ni0 or Fe0/ Ni0.
Comparing the removal efficiency of nitrates by adding nanoscale Fe0, Ni0 or Fe0/ Ni0, it can be found that the adding of bimetallic Fe0/ Ni0 can get the better removal efficiency than nanoscale Fe0 or Ni0. Meanwhile, the higher of the ratio of Fe0 in bimetallic Fe0/ Ni0 can attain the better removal efficiency on nitrates.
This study is also to compare the removal efficiency of nitrates by adding combinedly or separatedly synthesized nanoscale Fe0/ Ni0. Results show that combinedly synthesized could attain the better removal efficiency on nitrates than separatedly synthesized.
In addition, DO content in water body can not affect the removal of nanoscale zero-valent metals on nitrates.
Keywords: bimetallic iron/nickel, nitrate, naoscale iron, nanoscale nickel.
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