부산대학교 도서관

The subject of this Phase I SBIR project was to remove volatile metals from high-temperature coal-conversion gas streams. Other researcher have found that alumina- and silica-containing materials have the ability to remove some metals (e.g. cadmium and lead) and alkali metals (sodium and potassium) from high-temperature gas streams. Little work has been reported in using these materials for the capture of volatile metals (mercury, selenium, arsenic) from high-temperature gas streams. ADA developed a laboratory test fixture to evaluate twenty materials for capturing mercury, arsenic and selenium. Test materials were obtained from suppliers and evaluated at 750{degrees}C in two test series. An initial screening test showed that two materials--an alundum (aluminum oxide) and a modified zeolite (an alumino silicate)--were found to capture mercury. A follow-on test was performed where a full suite of gas constituents (CO, CO{sub 2} H{sub 2}O, NH{sub 3}, N{sub 2}, and Hg{sup 0}) was passed through beds of the two materials. The materials showed a mercury capture rate of 10%-15%. The alundum was also subjected to arsenic and selenium vapor and found to be ineffective at capturing these metals. One of the materials that was found to be ineffective at removing mercury during the screening test was a commercial zinc titanate. This material is ordinarily used to remove hydrogen sulfide from coal-conversion gas streams. It was of interest to evaluate whether it would also remove mercury, and thus provide a one-step contaminant removal process. Since it di not remove mercury, it is apparent that additional sorbents or an additional process will be needed to remove volatile metals.