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Title 利用化學活化法將澱粉廢料製成高比表面積含硫除汞活性碳新穎技術及其設備之研發
Abstract 本計畫主要目的及工作項目包括兩大部份:(1)進行澱粉廢料之氣化發電研發,並完成成本估算及經濟影響評估;(2)以價廉而量大之澱粉廢料為原料,經化學活化法來製備高比表面積之活性碳材料,且無需繁複的設備及步驟即可量產高比表面積活性碳之優點,並使用硫含浸法進行表面改質,以提升其吸附去除含汞污染物之特殊能力。實驗結果顯示澱粉廢料經過化學活化處理程序後,比表面積從54提升至923 m2/g。澱粉廢料氣化為二階反應,平均活化能為10.3~18.2 kcal/mol,平均反應次數為2,冷氣效率為73.6%,合成氣產量約95.5%,可回收熱能1.77 × 107 kcal/h;汞吸附量與吸附比表面積略成正比的趨勢,且硫含量愈高,吸附汞能力愈佳。由BET結果顯示此硫化活性碳吸附劑經改質後,比表面積都明顯降低,可能是因改質後披覆在孔洞表面的可能產物如硫或硫醇基之化合物,造成孔洞堵塞而降低比表面積。由EXAFS分析可說明汞之氧化價數主要為二價,可能是因在高溫下Hg(I)較不易形成,其中HgO、HgCl2及HgS之配位數分別為2、4和2,鍵距分別為2.10、2.31及2.42 Å。此外,Hg在高溫下可能與空氣中之氧或尾氣之氯形成HgO或HgCl2,但更容易與吸附劑表面之硫,形成HgS鍵結。此硫化活性碳具有吸附力強而且價格低廉之優點,具有商業競爭優勢及前瞻性經濟效益。
EngTitle Technical Development for Advanced High-Surface-Area Presulfurized Activated Carbon from Starch Wast
EngAbstract The objectives and major tasks of the proposed research were comprised of: (1) starch wastes gasification with syngas (H2 +CO) generation and tested/simulated assessment of the gasification pilot plant and economic estimation; (2) synthesized and characterization of high-surface-area presulfurized activated carbon obtained from starch wastes using chemical activation. The surface area of as-synthesized activated carbon was notably enhanced from 54 to 923 m2/g by chemical activation. In addition, the starch waste gasification was a two-order reaction with an average activation energy of 10.3~18.2 kcal/mol including cold gas efficiency of 73.6% and 1.77 × 107 kcal/h of heat recovery. Moreover, the generation of syngas (H2 + CO>95.5%, dry basis) was also recovered. The Hg adsorption capacity of as-synthesized activated carbon was increased with increasing the surface area and content of sulfur in activated carbon. Since the pore channels of as-synthesized activated carbon may be pluged with sulfur, thiophene, sulfate, sulfone or sulfoxide, the BET surface area was decreased with increasing sulfur content in the pre-sulfurised activated carbon. The postulated mechanisms of the adsorption of HgCl2 and Hg(0) might be chemically and physically adsorbed on the surface of pore channels, respectively. The XANES and EXAFS data showed that the adsorbents possessed Hg(II) species in a higher temperature environment. The main species in adsorbents were HgO, HgCl2, and HgS with the bond distance of 2.10, 2.31, and 2.42 Å and the coordination number of 2, 4, and 4, respectively. The starch wastes wth highly Hg adsorption capacity and cheap would have the particular economic potentials and low-cost advantages in the application of Hg removal.
ProjectYear 098
SponsorOrg 永續發展室
ExecutingOrg 元智大學
PublicFullVersionURL http://epq.epa.gov.tw/project/FileDownload.aspx?fid=16714