本研究之主要目的在於再利用廢牡蠣殼作為氟和硼吸附之吸附劑，並研究熱處理對牡蠣殼基本性質以及氟和硼的去除效率的影響。將乾淨的牡蠣殼廢料樣品分別於500°C下2小時（OS500-2h），700°C下0.5小時（OS700-0.5小時）和2小時（OS700-2h）進行預處理，並使用預處理之牡蠣殼樣品去除氟和硼。我們利用比表面積與孔隙度分析儀(BET)，傅里葉轉換紅外光譜(FTIR)，X射線衍射(XRD)，熱重力分析(TGA)和X-射線光電子光譜(XPS)分析未負載和負載的吸附劑的特徵。
研究結果顯示，以預熱處理使牡蠣殼樣品之純度提高，導致pHIEP向鹼性範圍偏移，而使得牡蠣殼樣品的去除效率提高。對於除氟，實驗符合Langmuir等溫線模型，牡蠣殼OS700-2h表現出最好的吸附性能，具有最大吸附量，Qo ， 6.14 mg/g，並在牡蠣殼表面形成氟化鈣 (CaF2) 沉澱。而對於除硼，牡蠣殼OS700-0.5h觀察到具有最大吸附量0.39 mg/g，並形成硼酸鈣 (Ca2B2O5) 沉澱。在氟化物和硼的吸附程序中，pH 7的去除機制主要是沉澱程序，其中牽涉到預熱處理產生的氧化鈣 (CaO) 的存在。總而言之，廢牡蠣殼具有再利用為低成本吸附劑之可行性，可從水中去除氟化物和硼酸鹽。

This study focused on the utilization of waste oyster shell as adsorbents for fluoride and boron removal. The effects of thermal pretreatment on the properties of oyster shells and on the removal efficiency of fluoride and boron removal were investigated. Waste oyster shell samples were pretreated at 500oC in 2 h (OS500-2h), 700oC in 0.5 h (OS700-0.5 h) and 2 h (OS700-2h). The characterization of unloaded and loaded adsorbents were analyzed by BET, FTIR, XRD, TGA and XPS. The experimental results fitted well with the Langmuir adsorption model. Results showed that thermal pretreatment led to the higher purity of preheated oyster shell samples and the shift of pHIEP to more alkaline range, resulted in the enhancement of the removal efficiency of oyster shell samples. For fluoride removal, the oyster shell OS700-2h showed the best performance, having the maximum adsorption capacity of Qo at 6.14 mg/g. The CaF2 precipitate formed on the oyster shell surfaces. For boron removal, the maximum adsorption capacity of Qo at 0.39 mg/g was observed for oyster shell OS700-0.5h, and the precipitate of calcium borate (Ca2B2O5) formed as well. For both fluoride and boron removal, the main mechanism was precipitation process for ≤ pH 7, which involved the presence of CaO. In general, the waste oyster shell could be a potential low-cost adsorbent for fluoride and borate removal from water.

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