습식산화를 이용한 TOC, T-N, T-P 동시산화 연구

국문 초록 (Abstract)

목적: 본 연구는 습식산화 방법을 활용하여 총 유기탄소(TOC), 총 질소(T-N), 총 인(T-P)의 동시산화 및 측정 가능성을 확인하였다.
방법: 유기질소 및 유기인을 포함하는 시료에 과황산나트륨(Na₂S₂O8)과 수산화나트륨(NaOH)을 공급하고 UV 254nm 및 40℃ 조건에서 황산라디칼(SO₄<SUP>-</SUP>·)과 수산화라디칼(OH･)의 활성화를 유도했다. 생성된 2종류의 라디칼을 통해 시료를 산화하고 TOC, T-N, T-P값을 공정시험법으로 분석한 대조군과 비교하여 동시산화 가능성을 평가하였다.
결과 및 토의: 본 연구에서 제안한 습식산화방법은 0.3 M의 낮은 과황산염 농도를 사용하였으나 모든 시료에서 고온연소산화기기에 대응하는 TOC 측정 결과 값을 나타내어 우수한 산화력을 증명했다. 또한 실험과정에서 발생한 T-N, T-P 측정오차를 개선하기 위해 제안된 추가공정은 UV-VIS 측정 간섭을 감소시켰다. 두 지표에서 모두 UV 처리보다 열처리가 간섭 제거에 더 효과적이었으며 온도와 시간이 증가할수록 그 효과가 극대화되는 것으로 나타났다.
결론: 습식산화를 활용하여 세 지표를 동시에 측정할 수 있음을 확인하였다. 제안된 방법은 적은 시료로 단시간에 세 지표를 분석할 수 있을 것으로 기대된다. 그러나 정확도를 향상시키기 위해 방해요인을 보다 효과적으로 제거할 수 있는 방법에 대한 추가적인 연구가 필요하다.

다국어 초록 (Multilingual Abstract)

Objective : This study proposed the simultaneous multi-oxidation of total organic carbon, total nitrogen, and total phosphorous using modified wet chemical oxidation method.
Methods : The multi oxidation process was based on the dual radical system with sulfate and hydroxyl radicals. The sodium persulfate (Na₂S₂O8) and sodium hydroxide (NaOH) were activated at 40℃ and UV irradiation with 254 nm to generate the sulfate radical and hydroxyl radical. The organic matters were oxidized by the dual radicals, and TOC, TN, and TP values were compared with the control group.
Results and Discussion : The dual radical system oxidized organic carbon to carbon dioxide effectively, and the TOC values were similar to the value obtained from the high-temperature combustion technique. However, the residual persulfate after oxidation process interfered the absorbance for TN and inhibit the complexation in TP measurement. The residual persulfate was effectively converted to sulfate by longer heating and UV irradiation, and the interferences were more sensitive to reaction temperature than UV irradiation time. As a result, a higher temperature condition was more effective and enhanced the applicability of multi-oxidation.
Conclusions : The multi oxidation of TOC, TN, and TP was demonstrated by wet chemical oxidation, and the proposed method is expected to secure the sample and reduce the analytic time. However, the more suitable condition to enhance the accuracy of TOC, TN, and TP in the multi-oxidation system should be studied further.

목차 (Table of Contents)

• 1. 서론
• 2. 실험방법
• 3. 결과 및 고찰
• 4. 결론
• References

참고문헌 (Reference)

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