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年度	111	專案性質	實驗性質
專案類別	研究專案	研究主題	整治
申請機構	國立臺灣大學	申請系所	生物環境系統工程學系
專案主持人	潘述元	職等/職稱	助理教授
專案中文名稱	生物炭水膠複合材料於穩定土壤重金屬與增強碳匯之績效評估
中文關鍵字	資源化材料, 重金屬, 生物炭, 碳中和, 韌性整治
專案英文名稱	Performance Evaluation of Biochar Hydrogel Composite for Soil Heavy Metal Stabilization and Carbon Sink Enhancement
英文關鍵字	Circular materials, heavy metal, biochar, carbon neutral, resilient remediation
執行金額	950,000元
執行期間	2022/5/1 至 2023/4/30
計畫中文摘要	為實現綠色土壤韌性整治，結合土壤重金屬控制、農業廢棄物資源化及土壤碳匯等前瞻國際趨勢，本研究開發生物炭-水凝膠複合材料，利用生物炭之高穩定結構性質作為基質，搭配具有三維交聯結構之水凝膠材料，製作成一複合材料，進行土壤中重金屬固定或去除。本研究一方面透過此複合材料之高重金屬吸附容量，減低重金屬於土壤中移動之能力；另一方面，水凝膠可實現土壤營養鹽與水分保持之功能，減少農業非點源污染，並增加作物與土壤健康程度；同時，此材料最終能將生物炭作為一儲碳媒介，增強土壤碳匯量，協助貢獻我國淨零排放之目標。本計畫主要研究目標包括研析國際間跨域新興資源化材料之進展；（二）開發新穎生物炭水凝膠複合材料，建立本土資源化複合材料製備程序；（三）使用實際受污染土壤樣本進行試驗，評估複合材料對於土壤重金屬吸附等功能之績效，並鑑別材料關鍵物化性質與土壤重要功能之關聯性；（四）建立資源化複合材料之反應動力學與等溫吸附模型，並研擬可行之資源化複合材料使用規範。 根據本計畫實驗結果顯示，新穎複合材附對於水溶液中Cu2+之去除效率至少可達94.7%；對於水溶液中Pb2+之去除效率可達73~89%。根據測得實驗數據及Cu與Pb各自電位-pH圖，顯示兩種重金屬於實驗環境中之主要物種為離子態，去除機制主要為離子型吸附，並未產生沉澱。此外，於建立動力學與熱力學模型，本計畫開發之三種配方複合材料，分析其在液相試驗吸附銅/鉛離子時，偽二階動力學模型可更好地模擬吸附行為，且進行吸附時主要以化學性吸附為主要吸附方式。最後，本計畫亦進行實際受污染土壤試驗，結果顯示：添加複合材料（配比100：5）銅離子減少14.4 %，鉛離子減少10.4 %；添加複合材料（配比100：10）銅離子減少20.1 %，鉛離子減少24.2 %。綜合以上，施用複合材料於污染土壤確實能減少土壤中的銅/鉛離子含量。此外，本研究發現施用生物炭-水凝膠複合材料對於土壤有機碳含量提升有顯著貢獻，相較於未施肥組別（做為基線），同時施用肥料及複合材料可提升土壤總有機碳含量約五倍，然對此增加之土壤有機碳長期儲存能力，仍需額外長期試驗驗證。
計畫英文摘要	For the sake of green soil resilience remediation (combined with important international trends such as soil heavy metal control, agricultural waste circulation, and soil carbon sequestration), this research project aims to develop a biochar-hydrogel composite material. This composite material incorporates the highly stable structural properties of biochar as a matrix, and combines with a hydrogel material with a three-dimensional cross-linked structure. The composite material can be used to fix (or immobilize) heavy metals in soil due to its high adsorption capacity of heavy metal, thereby reducing the mobility of heavy metals in the soil. The composite can also realize the function of soil nutrient and water retention, reduce agricultural non-point source pollution, and increase crop and soil health. In the meantime, the composite material can be ultimately considered as a carbon storage medium to enhance soil carbon sink and help contribute to our country's goal of net zero emissions. The objectives of this project are (1) to review the international progress on circular materials, and their ability to improving soil properties and enhancing soil carbon sinks; (2) to develop a biochar-hydrogel composite using agricultural byproducts as a raw material, and its associated the preparation process; (3) to evaluate the performance of composite materials on soil heavy metal adsorption using the real polluted soils with representative crops, and identify the correlation between physico-chemical properties of composite materials and important soil functions; (4) to establish reaction kinetic and isothermal adsorption models for the developed composite materials, and propose the standard operation procedure for the develop composite materials. The results of this study show that the removal efficiency of the novel composite material for Cu2+ in aqueous solution is at least 94.7%. For Pb2+ in aqueous solution, the removal efficiency can reach 73-89%. Based on the experimental data obtained and the potential-pH diagrams for Cu and Pb, it is evident that the main species of these two heavy metals in the experimental environment are in ionic form, and the removal mechanism is primarily ion exchange adsorption without precipitation. In addition, by establishing kinetic and thermodynamic models, three formulated composite materials developed in this study were analyzed for their adsorption behavior in liquid-phase tests for copper/lead ions. The pseudo-second-order kinetic model better simulated the adsorption behavior, indicating that chemical adsorption is the main adsorption mechanism during the adsorption process. Finally, actual contaminated soil tests were conducted, and the results showed that the addition of the composite material (at a ratio of 100:5) reduced copper ions by 14.4% and lead ions by 10.4%. With the addition of the composite material (at a ratio of 100:10), copper ions decreased by 20.1% and lead ions decreased by 24.2%. It suggests that the application of the composite materials to contaminated soil effectively reduces the levels of copper/lead ions in the soil. Furthermore, the results indicate that the application of composite materials in soil can significantly enhance the content of total organic carbon in soils. The total organoc carbon content in soil for the group of fertilization with composite materials is found to be 5-folds higher than of the baseline (without fertilization and composite materials).