炭化農業廢棄物改良水田重金屬污染之研究

The Effects of Carbonized Agricultural Wastes on Remediating Heavy-metal Polluted Paddy Soil

劉黔蘭(Chyan-Lan Liu) ； 黃瓊慧(Chiung-Hui Huang)

《土壤與環境》 10卷1&2期 (2007/06) Pp. 43-52

https://doi.org/10.30058/SE.200706.0004

摘要

台灣農業廢棄物產量非常大，需要適當處理不致造成環境的污染。某些農業廢棄物經炭化及活化製成活性炭後，可增加其比表面積及孔隙而能吸附污染物，故本研究之目的希望能利用碳化農業廢棄物作為重金屬污染的吸附劑，研究其在土壤重金屬污染改良上的可行性。土樣採集自彰化縣受重金屬污染的水稻田。選擇稻殼、蔗渣、花生殼、玉米穗軸及廢竹為測試農業廢棄物，經高溫炭化及C02活化，並以市售活性作比較，進行吸附水溶液重金屬試驗，測試其吸附重金屬能力。在不同濃度重金屬溶液中，炭化農業廢棄物吸附量會隨溶液濃度的提高而有增加的趨勢，且以炭化花生殼對水溶液重金屬的吸附量最大，炭化蔗渣吸附量次之。並利用EDTA震盪萃取土壤重金屬，以炭化農業廢棄物進行震盪吸附試驗及淋洗吸附試驗測試其吸附土壤EDTA-重金屬能力，兩試試驗結果顯示，六種供試物中炭化蔗渣的吸附效果較佳，炭化花生殼之吸附效果次之。整體而言，炭化玉米穗軸 為六種炭化農業廢棄物中吸附量較差者，原因可能為炭化玉米穗軸之比表面積小吸附量低，使得其吸附能力較差。

關鍵字

活性碳 ； 農業廢棄物 ； 吸附 ； 重金屬

並列摘要

Agricultural wastes in Taiwan are mass-produced and need befitting attention to avoid pollution. Some agricultural wastes may be carbonized and activated to increase specific surface area and pore size to absorb more pollutants. Therefore, the purpose of this study was to evaluate the feasibility of remediating heavy-metal polluted soil by using these carbonized agriculture waste as absorbent for heavy metals. The tested soil samples were collected from heavy-metal polluted paddy soil of Changhua. Rice hulls, bagasse, peanut hulls, corncob, and bamboo were chosen as tested agricultural wastes, which were carbonized by high temperature and activated by CO2. The ability to absorb heavy metal in solution was tested and compared to the commercially available activated carbon. When different concentrations of heavy metal solution were used, the adsorbed amounts of heavy metals by carbonized agricultural wastes increased with increasing concentrations. Among all wastes and active carbon tested, carbonized peanut hulls adsorbed the highest amount of heavy metals, followed by carbonized bagasse. To study the adsorbing ability of the carbonized agricultural wastes from polluted soils, EDTA-chelated heavy metals by agitation and leaching were measured. Carbonized bagasse absorbed the highest amount of heavy metals by agitation and leaching followed by carbonized peanut hulls. Among all agricultural wastes tested, carbonized corncob adsorbed the least possibly due to its low BET surface area.

並列關鍵字

Activated carbon ； Adsorption Agricultural wastes ； Heavy metal