利用生物吸附劑動態吸附水溶液中重金屬

Removal of heavy metals using biosorbents from aqueous solution

張丞笉(Cheng-Chen Chung)

指導教授 ： 趙煥平

中原大學/工學院/土木工程研究所/碩士(2011年)

https://doi.org/10.6840/cycu201100732

摘要

摘要
傳統上處理重金屬廢水之方法包括化學沉降、離子交換、吸附、膜處理及電透析等。對低濃度廢水最常使用的方法為離子交換法，但離子交換的樹脂製作成本較高，因此近年來已有許多研究人員致力於開發低成本、吸附容量大並且對環境親和力高的生物吸附劑來處理這些有害重金屬。
本篇研究主要選擇柚子皮、百香果殼與甘蔗渣，利用簡單化學處理技術將其轉換成富含COOH官能基之生物吸附劑；並在動態下針對不同pH值與流速對Cu2+、 Cd2+、 Ni2+、 Pb2+之重金屬溶液進行吸附實驗。實驗結果顯示柚子皮與百香果殼具有相當良好的吸附效果，除了吸附劑表面具有離子交換的能力外，由FTIR圖譜可看出吸附劑表面具有相當大量的羧基與氫氧基吸收波峰，吸附後峰值有明顯的削減，表示果皮表面帶有的羧基與氫氧基官能基可提供未共用電子對與重金屬鍵結，達到吸附效果。
動態吸附結果顯示柚子皮與百香果殼在pH = 5時吸附效果最好，而甘蔗渣則是在pH = 6時效果最好。不論是在吸附平衡或是動態吸附下，吸附劑所產生吸附量之順序為：柚子皮 >百香果殼 >甘蔗渣。而對重金屬的吸附量大小順序為：鉛 > 鎘> 銅> 鎳。最大吸附量分別為：248,500、191,652、117,057、86,422 mg/Kg 。

關鍵字

管柱試驗 ； 吸附 ； 生物吸附劑 ； 重金屬

並列摘要

The methods of treating effluent contained heavy metals traditionally include precipitation, ion exchange, adsorption, membrane processing and electro dialysis. Ion exchange is the most common method for removal of the low concentration heavy metals in the effluent. However, resin possesses high production costs. A number of researchers, therefore, have dedicated to develop biosorbents with the low-costs, high adsorption capacity and environmental affinity to remove the harmful heavy metals in recent years.
The primary purpose of study is to select fibrous materials, such as citrus maxima, passion fruit shell and sugarcane bagasse, to produce the biosorbents with bio-rich COOH functional groups using simple chemical processing. The obtained biosorbents are used to absorb the heavy metals of Cu2+、 Cd2+、 Ni2+、 Pb2+ by column in accordance with difference between the pH values and flow rates. The results indicate the biosorbents from the citrus maxima and passion fruit shell possess high adsorption capacities. FTIR spectra can exhibit the adsorbent surface which is equipped with functional groups of carboxyl and hydroxyl. The functional groups provide nonbonding electron pair bonding to heavy metals with achieving the adsorption results. The test of cation exchange capacity demonstrates the surfaces of adsorbents possess negative charge that can absorb heavy metal ions by the ion exchange. The study indicates that citrus maxima and passion fruit shell produce the highest adsorption capacities at pH = 5, whereas sugarcane bagasse is at pH = 6. For the adsorption equilibrium and dynamic column experiments, adsorption capacities for all heavy metals are the following order: citrus maxima > passion fruit shell > sugarcane bagasse. The adsorption capacities for heavy metal are: Pb> Cd> Cu> Ni.

並列關鍵字

Column ； Heavy metal ； Biosorbent ； Adsorption

參考文獻

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