隔熱材珍珠岩表面特性及其應用潛能之研究

為因應能源短缺，珍珠岩近年來成為防火、隔熱及保溫材料之新寵兒。本研究從目前常用的隔熱材料切入，介紹、比較各類隔熱材之優缺點及溫度需求適用性。針對中國、日本、菲律賓三產地之珍珠岩精石以不同溫度進行膨化實驗量測其膨脹倍數及容重，探討溫度對膨化程度之影響，結果顯示950度為各產地珍珠岩之最佳膨化溫度；以化學成分分析三產地之珍珠岩，並比較各膨化數據可知，日本珍珠岩因雜質含量較少而有最高膨化倍數及最小容重。另研究珍珠岩於隔熱材料外之用途，本研究特別針對各產地精石與膨化產物表面特性進行研究，結果顯示其比表面積介於0.14~5.63 m2/g，並由SEM表面影像觀測獲得珍珠岩於不同溫度之表面特性，符合高溫破壞使膨化後產物比表面積較精石略小，但內部膨化使容重變小之結果。本文亦研究珍珠岩對環境中常見重金屬物質:Cu、Cd、Zn之吸附特性，結果顯示珍珠岩對重金屬吸附等溫線呈線性，且對Zn具有較高之親和力，對Cd則親和力相對較低，各組合吸附量均與珍珠岩比表面積大小呈現正相關，但由於珍珠岩所具有之比表面積較一般土壤小，故使其吸附能力亦較一般土壤為低。真珠岩在商業用途上常做為隔熱材料，但針對珍珠岩膨化後顆粒表面特性之研究則少有人探討，若能發展相關技術進行改良，保持顆粒完整之表面特性，並尋找其他添加介質，則可開發出隔熱材料以外之用途。

關鍵字

容重；膨脹倍數；珍珠岩

並列摘要

Shortages of energy resource result in perlite becomes an important material of fire prevention, heat insulation and keep warm in the recent years. In this study, the familiar heat insulation material was introduced and then, the advantage and disadvantage, and different calcined temperature of these materials were discussed. In order to investigate the effects of the calcined temperature on swell level of the perlites, the raw materials of the perlite produced from China, Japan, and Philippine were calcined under different temperature to examine their swell level and volumetric weight. The results indicate the best swell level was set as 950oC. By analyzing chemical components of the perlites form three countries and differentiating the swell level of the calcined perlites, the perlite from Japan possesses the highest swell level and the lowest volumetric weight because the perlite contains the least impurity. Besides heat insulation materials, the surface characteristics of raw materials of the perlites and the expanded perlites are also examined. The result indicates the specific surface area of the perlite is ranged from 0.14 to 5.63 m2/g. The surface characteristics of the perlite under different temperature obtained from SEM demonstrates high temperature destroys the surface structure of expanded perlite to cause the lower specific surface area. Also, the amount of the perlite adsorbing heavy metals, Cu, Cd, and Zn, is studied. All of the isotherms obtained are linear. Among these heavy metals, Zn possesses the highest affinity with the pearlite but Cd possesses the lowest affinity. In addition, it can be found that the maximum adsorptive amounts of the heavy metals and the specific surface area of the perlite have the positive correlation. On the other hand, the perlite has the relative lower specific surface area than soil does. The amount of the heavy metals adsorbing on the perlite is lower than that on the soil. Commercially, the perlite frequently used as the heat insulation material. The change in the surface characteristics of the expanded perlite resulting from calcination is investigated scarcely. If the technique of the calcined perlite keeping the surface properties can be improved and the appropriate additive can be obtained, applicability of the perlite will increase significantly.