廢油汙染與廢棄溶劑量逐年成長且惡化，對於能夠處理並回收此類汙染物但又不會使環境造成二次傷害之油水分離材料的需求已迫在眉睫。此外，世界對於淡水資源的需求大幅增加，但以現有之海水淡化技術，依然存有高耗能、高成本等問題，使得近年來有許多研究開始轉向對於太陽能蒸餾技術的探討。
菱角殼是臺灣常見的農業廢棄物，銀合歡為臺灣之入侵外來種，會排放毒素來抑制本土植物的生長，嚴重壓迫到本土植物的生存空間。本研究便是使用以菱角殼與銀合歡為來源所製備之生物炭顆粒材料來進行乳化液分離以及太陽能蒸餾。
1.顆粒狀生物炭/高分子複合材料應用於分離水在油中乳化液
我們所選的顆粒狀生物炭/高分子複合材料具有多孔結構，並展現親水特性。將此類顆粒加入水在油中乳化液(water-in-oil emulsion)後，顆粒能夠在短時間內捕捉乳化液中之小水胞並吸附。將乳化液倒入填滿顆粒狀生物炭/高分子複合材料之管柱，靜置5分鐘後濾液油純度超過99.99 wt%。同批顆粒連續以批式法分離10次後，濾液依然維持99.98 wt%以上的油純度。顆粒狀生物炭/高分子複合材料也可應用於奈米乳化液分離。顆粒經乾燥後便能夠再次使用，效率無明顯下降，具高度重複使用性。
2.顆粒狀生物炭/高分子複合材料應用於太陽能蒸餾
我們利用顆粒狀生物炭/高分子複合材料於一倍太陽光照射下(1000 W m-2)進行太陽能蒸餾實驗。由於顆粒本身的親水性與毛細現象，在光熱蒸發過程中，水分會不間斷地往上輸送，純水蒸發效率最高可達3.2 kg m-2 h-1，模擬海水的蒸發效率也能夠擁有3.0 kg m-2 h-1的表現。連續使用8小時後生物炭/高分子複合顆粒表面會有鹽類結晶生成並降低蒸發速率，將裝置移開光源30分鐘後，表面鹽類結晶便會因溶解於水溶液而去除，具有優異之重複使用性。

Effective methods to separate the oil/water emulsions are urgently needed to address environmental and ecological problems caused by this waste. Water scarcity is one of the most critical global challenge, and has thus attracted significant attention. In this study, we use bead-like biochar/polymer composites to separate water-in-oil emulsions and perform solar evaporation. The biochar used in this study was prepared from water chestnut shell or white popinac.
Water caltrop shell is a common agricultural waste in Taiwan. White popinac is an invasive alien species in Taiwan. It emits toxins to inhibit the growth of native plants, severely oppressing the living space of native plants. In this study, we reported two biochar/polymer composites from water chestnut shell and white popinac for emulsion separations and solar distillations.
1.Bead-like biochar/polymer composites for water-in-oil emulsion separation
The bead-like biochar/polymer composites possessed porous structures with superhydrophilicity. After adding into water-in-oil emulsions, our beads can capture and absorb the small water micelles from emulsions rapidly. We pour the water-in-oil emulsion into the column filled with beads, then stand the emulsion for 5 min, the oil purity of the filtrate is greater than 99.99 wt%. After separating the emulsions for 10 times with the same batch of the beads, the filtrate still maintains an oil purity greater than 99.98%. Our materials also can be used to treat nano-emulsions. After drying, the bead-like biochar/polymer composites can be reused, with no significant decrease in separation efficiency.
2.Bead-like biochar/polymer composites for solar evaporation
We perform solar evaporation tests through using bead-like biochar/polymer composites under one sun irradiation (1000 W m-2). Due to the hydrophilicity of the beads, the water will be continuously transported upward during the solar evaporation process. The evaporation rates were up to 3.2 and 3.0 kg m-2 h-1 for pure water and simulated seawater, respectively. After continue use for 8 h, some salt particles formed on the surface of the beads and reduced the evaporation rate. After we turning off the light for 30 min, the salt particles will be dissolved by the aqueous solution. Our materials showed excellent reusability.

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