以離子交換樹脂與界面活性劑去除全氟丁烷磺酸之研究

Abstract

全氟化合物(Perfluorinated chemicals, PFCs)為生活及工業製程常見之化學物質。長碳鏈 PFCs 在過去被廣泛使用，但隨著其毒性及持久性被揭露，各國逐漸禁止使用，短碳鏈 PFCs 則取代而代之，如全氟丁烷磺酸(Perfluorobutanesulfonic Acid, PFBS)。但仍有研究指出短碳鏈 PFCs 亦具毒性及持久性，因此研究短碳鏈 PFCs 之去除有其重要性。 本研究利用離子交換樹脂(IRA402)去除水中 PFBS。對離子交換樹脂進行界達電位、表面結構、元素組成、化學鍵及官能基分析，並探討 PFBS 初始濃度、離子交換樹脂添加量、攪拌速率、水溶液 pH 值等對去除效果之影響，找出較佳之實驗參數。在這些參數條件下，添加陽離子界面活性劑(DTAB、TBAB)及陰離子界面活性劑(SDS)，探討界面活性劑對離子交換效果之影響。研究結果顯示，實驗參數為 PFBS 初始濃度25 ppm、水溶液 pH 3、常溫、攪拌速度為400 rpm、離子交換樹脂添加量為2 g/L 時，添加1mM TBAB 效果最佳，30分鐘即達到100%去除率，較未添加界面活性劑者縮短10分鐘，交換量為12.94 mg/g；5分鐘時，去除率可提升20.86%；在不同 PFBS 初始濃度下，添加 TBAB 均可提升交換速率。在PFBS 初始濃度100 ppm，其他實驗參數不變之情況下，添加1mM SDS 會產生反應時間較長且具去除率較差之負面影響。經反應動力模式模擬之結果顯示，實驗符合擬一階反應動力模式。

Perfluorinated chemicals (PFCs) are common substances used in daily life and industrial processes. Long-chain PFCs were widely used in the past, but as their toxicity and persistence have been revealed, many countries have gradually banned their use and replaced them with short-chain PFCs, such as Perfluorobutanesulfonic Acid (PFBS). However, studies have indicated that short-chain PFCs also exhibit toxicity and persistence, making the study of the removal of short-chain PFCs important. This study utilizes ion exchange resin (IRA402) to remove PFBS from water. The zeta potential, surface structure, elemental composition, chemical bonds, and functional groups of the ion exchange resin were analyzed, and the effects of PFBS initial concentration, ion exchange resin dosage, stirring rate, and solution pH on the removal efficiency were investigated to determine the optimal experimental parameters. Under these conditions, cationic surfactants (DTAB, TBAB) and anionic surfactants (SDS) were added to explore the effect of surfactant on the ion exchange efficiency. The results showed that with an initial PFBS concentration of 25 ppm, solution pH of 3, room temperature, stirring speed of 400 rpm, and ion exchange resin dosage of 2 g/L, the addition of 1 mM TBAB resulted in the best performance, achieving a 100% removal rate within 30 minutes, 10 minutes shorter than without surfactant addition, with an exchange capacity of 12.94 mg/g. The removal rate could be increased by 20.86% within 5 minutes. The addition of TBAB improved the exchange rate across different initial PFBS concentrations. At an initial PFBS concentration of 100 ppm, with other experimental parameters unchanged, the addition of 1 mM SDS had a negative impact, leading to longer reaction time and lower removal rate. The reaction kinetics modeling results indicated that experiments followed the pseudo-first-order reaction kinetics model.