乙二醇改質奈米零價鐵降解氯黴素

氯黴素(CAP)在抑制細菌上具有好的效果，且生產成本低廉，於是被廣泛應用，但CAP對於人體健康擁有危害，因此在許多國家受到限制及控管更甚於禁止使用。奈米零價鐵(nZVI)具有高反應性、比表面積高、環境友善性、較低廉的成本、處理對象廣泛等優點，但其合成方式大多需在缺氧環境中進行，添加乙二醇(EG)能使nZVI在大氣條件下製備合成。本研究目的主要探討乙二醇改質的nZVI較傳統合成方法更具有優勢和耐久性，以及操作參數如CAP濃度、反應溫度、還原劑劑量的改變對於降解CAP之影響。結果顯示，在第0天，添加乙二醇之nZVI(S-nZVI-EG)對氯黴素的去除率為98.7 %、kobs為0.0495 min-1，傳統合成方式之nZVI(S-nZVI-N2)對氯黴素的去除率為93.7 %、kobs為0.032 min-1；經過30天的S-nZVI-EG對氯黴素的去除率降至41.1 %、kobs為0.0064 min-1，S-nZVI-N2對氯黴素的去除率僅剩5.0 %、kobs為0.0007 min-1，因此證明乙二醇改質後的nZVI不管是在降解CAP或者耐久性上皆更具有優勢。0.5 g的S-nZVI-EG能有效降解500 mg/L CAP，去除率可達到99.0 %；反應溫度從15 ℃升至35 ℃時，雖然CAP去除率可達到96.8~100 %，但35 ℃之kobs為15 ℃的2.2倍；S-nZVI-EG從0.1 g添加至0.5 g，CAP去除率從45.3 %提高至100 %，且0.5 g之kobs是0.1 g的15.1倍，證實提升反應溫度及增加劑量有利於CAP降解。

關鍵字

氯黴素；奈米零價鐵；乙二醇

並列摘要

Chloramphenicol (CAP) has a good effect on inhibiting bacteria, and the production cost is low, so it is widely used. However, CAP is harmful to human health, so it is restricted, controlled and even prohibited in many countries. Nano-scale zero valent iron (nZVI) particles possess many advantages, such as high reactivity, high specific surface area, environmental friendliness, low cost and wide range of treatment objects. But most of its synthesis methods need to be carried out in an anoxic environment, addition of ethylene glycol (EG) can make nZVI be preaped and synthesized under ambient conditions. This main objective of this study is to explore that nZVI modified by EG possess more advantages and durability than traditional synthesis methods, and the impact of changes in operating parameters such as CAP concentration, reaction temperature and reducing agent dosage on the degradation of CAP. The results show that, on day 0, the removal rate (r) of CAP by nZVI (S-nZVI-EG) modified by EG was 98.7%, and its kobs was 0.0495 min-1, the traditional synthesis method of nZVI (S-nZVI-N2) has a r of 93.7% for CAP and a kobs of 0.032 min-1. After 30 days, r of CAP by S-nZVI-EG decreased to 41.1% wirh a kobs of 0.0064 min-1, while r of CAP by S-nZVI-N2 was only 5.0% with a kobs of 0.0007 min-1. Therefore, it is proved that the EG modified nZVI has more advantages in terms of degradation of CAP and its durability. S-nZVI-EG (0.5 g) can effectively degrade 500 mg/L CAP, and the r can reach 99.0%. As the reaction temperature raised from 15℃ to 35℃, the r of CAP was 96.8-100%, but the kobs at 35℃ was 2.2 times of that at 15℃. As the addition dosage of S-nZVI-EG increased from 0.1g to 0.5g, the r of CAP raised from 45.3% to 100%, and the kobs of 0.5 g was 15.1 times as much as that of 0.1g. It is confirmed that increasing reaction temperature and dosage are beneficial for degradation of CAP.