本研究之目的乃利用不同溫度600℃、800℃、900℃、1150℃燒製出之竹炭對液相中環境荷爾蒙雙酚-A之研究,探討雙酚-A在不同pH、溫度下之平衡吸附結果。初始平衡吸附條件由動態吸附實驗得知,達吸附平衡所需之時間(te)為24小時。
在不同溫度下BET比表面積與微孔面積間具有顯著的關聯性,當BET數值越大,相對的微孔面積也增大,然而在四種不同燒製溫度下之竹炭,其BET比表面積與微孔面積在600℃時最大,以1150℃時最小,由此可知,炭化溫度的控制為一大考量因素。
利用等溫吸附Langmuir模式,探討不同條件下的吸附劑之最大吸附量(qm)與為吸附質之平衡反應速率常數(KL),製備相同的竹炭溫度對不同pH吸附BPA之結果,隨者反應溫度增加而增加。由熱力學常數得到△G為負、△H為正及△S為正,所以吸附為自發性反應。 The objectives of this study were: 1) to characterize bamboo charcoals prepared at three different temperatures, and 2) to understand their adsorption behavior of Bisphenol-A (BPA) in water. Parameters studied during adsorption include temperatures at which bamboo charcoal was prepared, solution pH, and solution temperature.
It was found that correlation exists between BET surface area and micro-pore areas. As BET surface area increases, micro-pore area increases as well. Among four different charcoal temperatures, BET surface area is the largest at 600℃ and smallest at 1150℃. Therefore, temperature is an important factor in controlling bamboo charcoal preparation.
From equilibrium adsorption experiments, it was found that pH value and temperature of Bamboo charcoal can significantly affect BPA adsorption. Model fitting results from Langmuir adsorption isotherm indicate that the adsorption rate constant increases with increasing temperature. Values of the activation energy implied that the mechanism involved physical adsorption. Thermodynamic parameters obtained are as follow: △Go value is negative, △Ho value is positive, and △So value is positive. These values suggest that the adsorption process is spontaneous and endothermic.