以稻殼廢棄物資源化製備多孔矽基材料並探討其應用於VOCs與CO2吸附之吸附特性研究

Abstract

本研究擬將稻殼農業廢棄物再利用，以不同之方法(高溫鹼萃取水熱法、低溫萃取快速 水熱法以及氣膠凝合快速製程)製備成不同孔洞結構特性之多孔材料，並探討其在應用至吸 附VOCs 與CO2 時，這些中/微孔材料之孔洞結構特性對於VOCs 與CO2 吸附效能之影響。 本研究擬以三年之計畫期程，探討利用稻殼農業廢棄物資源化再利用，分別利用三種不同製 備方法來製備多孔吸附材料，並將所製得的多孔吸附材料分別對VOCs 和CO2 進行吸附行 為探討，以釐清一維、二維與三微孔洞結構、比表面積、中/微孔比例、孔徑大小等孔洞結 構特性對於VOCs 和CO2 之吸附效能影響，並獲得中孔洞材料最佳化組成配方與工業化製 造流程。 於第一年計畫中，本研究將以高溫鹼萃取水熱法將稻殼農業廢棄物中之矽化物萃取出， 以製備MCM-41、SBA-15與SBA-16三種多孔材料，藉由改變前驅物界面活性劑模板比例， 進而改變材料最終之孔洞型態，希望釐清孔洞結構特性對於VOCs(以丙酮及甲苯為代表污染 物種)吸脫附能力的影響。第二年計畫將比較低溫萃取快速水熱法與低溫萃取快速水熱法兩 種不同之矽化物萃取方法之優劣性，並藉由胺基改質之材料進行CO2吸附測試，以探討孔洞 結構特性對於CO2吸脫附能力的影響。在前兩年計畫找出最佳材料結構後，第三年之計畫則 將嘗試以氣膠凝合快速製程之方式製造多孔吸附材料，期能以工程化之氣膠凝合程序方式， 將稻殼快速資源化製造成多孔材料，並用以吸附VOCs與CO2兩種氣體，最後評估比較三年 計畫中所使用之三種不同吸附劑製造方法之成本效益與耗能。本研究預計在三年計畫結束後， 將可顯著降低材料製造成本，並設計出最適合應用於VOCs與CO2吸附之中孔洞材料，以獲 致更佳之吸附效能，方便推廣應用至實場中。

As the energy crisis and resource shortage continue, the rice husk agriculture waste becomes a valuable waste resource which can be made into various kinds of energy products and resource materials. On the other hand, the control of VOCs emitted from industrial sources and the capture of CO2 are two of the most important air pollution issues. This study intends to reutilize the rice husk as the silica source for the synthesis of porous silica materials and to investigate the effects of structural properties of the waste-derived-materials on VOCs and CO2 adsorption performance. Different manufacture methods on reutilizing the rice husk to make cost-effective adsorbents will be evaluated and compared. The adsorption behaviors of VOCs and CO2 appear to be quite different since the VOCs can be directly adsorbed by the adsorbents, while for the CO2 adsorption the adsorbents must be coated with appropriate reagents. On the other hand, the preparation method of the adsorbents may also result in different pore structures. This study will compare the pore structures of the adsorbents made by different adsorbent preparation methods, and evaluate these adsorbents for their performance on the VOCs and CO2 adsorption. This study will be a three-year project. For the first year, the fusion method will be employed to extract the silica from rice husk. And porous materials (MCM-41, SBA-15, SBA-16) of different pore structures will be obtained by adjusting the preparation conditions to understand the effects of pore dimension, surface area, the ratio of meso/micro structure and pore size on the VOCs adsorption. During the second year’s project, both the fusion and the low temperature fast extraction method will be employed for the extraction of silica from the rice husk. In addition, the pore structure effects of the adsorbents made by these two methods will be compared on their CO2 capture ability. And for the third year’s project, the one-step fast aerosol process will be studied to manufacture the best structured materials obtained from the first two years’ projects. Finally the cost-effectiveness and the energy consumption of the materials made by the three methods will be compared in terms of their VOCs and CO2 adsorption performances. As a result, it is expected to significantly reduce the manufacture cost, and design the appropriate materials which can obtain the best VOCs and CO2 adsorption performance.