碩士 / 嘉南藥理科技大學 / 環境工程與科學系暨研究所 / 91 / Diatomaceous earth, a clay mineral and characteristic of pore structure and
negatively polar nature in the surface, is used extensively as filter and/or
filter aid for the removal of all impurities in the industrial processes. The
spent diatomaceous earth is thus generated and mostly disposed of landfill
without further treatment for resource utilization.
The objective of this work is to study thermal regeneration by using
horizontally rotary activation furnace under different parameters. Further,
chemical activation has been carried out by using acid /alkaline agents such
as sulfuric acid, acetic acid, hydrochloric acid and sodium hydroxide, and
different activation parameter such as concentration, time and temperature.
Under the experimental conditions investigated, the thermal regeneration
process is not good for upgrading the physical properties of spent diatomaceous
earth, The impregnation conditions at concentration of NaOH 2.25 M,
impregnation temperature of boiling, holding time of 2 hr and sample/solution
ratio of 5/100 seemed to have the most determining effects on the development
of pores. The chemically activated clay have larger surface areas (109 vs 0.3
m2/g) and total pore volumes (0.26 vs 0.004 cm3/g) than those of the spent
diatomaceous earth.
The physical and chemical characterization of the resulting products obtained
in this study were further examined based on the analyses of surface area/pore
volume, scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier
transform infrared spectroscopy (FTIR) and main elements. Results showed that
these samples are characteristic of type IV from N2 isotherm, indicating
mesoporous structure. Further, the optimal porous material thus obtained was
used as mineral adsorbent for paraquat adsorption, showing that it has a good
adsorption capacities for removal of this organic contaminant from the
fittings of Langmuir and Freundlich isotherms.
| Identifer | oai:union.ndltd.org:TW/091CNUPS515007 |
| Date | January 2003 |
| Creators | Kuo-Jung Hsieh, 謝國鎔 |
| Contributors | 蔡文田 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 102 |
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