| 摘要: | 研究期間：10108~10207;Increasing generation of various sludges, sediments, and inorganic residues such as municipal/industrial incinerator ashes is posing an environmental problem facing society. Traditional treatment of such waste streams includes recycling as roadbed fill, artificial aggregates for concrete, replacements for par tof the raw meal for producing eco-cement, all targeting a recycling-benificial use of the residues to set-off part of the resources depletion problem. The traditional technologies for recycling the above sludges and residues into constructional materials is well developed and have long been practiced; the products, however, have less performance and lack of added value. Therefore, there is possibility to develop novel mesoporous aluminosilicate adsorbents from waste sludge and incinerator residues, that is functional, environmental-friendly, low-cost, and with high added values. The inorganic residues, especially the water-treatment sludge ash, are essentially composed of SiO2, Al2O3 . In addition, most of the mesoporous molecular sieves having been developed thus far are all of aluminosilicates or silicates. In fact, the mesoporous materials can be synthesized using a variety of silicate and aluminate precursors such as fume silica, sodium silicate, tetraethoxysilane, colloidal silica, catapal alumina, and sodium aluminate. However, they are all suffering form high producing costs. Therefore, if waste-derived silica and aluminum sources are used as precursors, this may provide an excellent opportunity to prepare mesoporous aluminosilicate adsorbents economically. This study try to develop a novel synthesis approach for preparing cost-efficient mesoporous aluminosilicate adsorbents from sludge and incinerator residues. The research work is devied into two phases: First year: Development and Application of Mesoporous Aluminosilicate Adsorbents from Waste Sludge and Incinerator Residues(l/2)--Synthesis and Characterization of mesoporous aluminosilicate. Second year: Development and Application of Mesoporous Aluminosilicate Adsorbents from Waste Sludge and Incinerator Residues (2/2)--Surface modification of mesoporous aluminosilicate and its application to toxic oxyanions adsorption. The first year: the study focused on the preparation of a mesoporous aluminosilicate molecular sieves (i.e., Al-MCM-41and Al-MCM-48). The mesoporous molecular sieves are formed by fusion with NaOH with Si and Al species extracted from sludges and incinerator residues as precursors, followed by hydrothermal reaction. The solid residue arising from silica extraction is also simultaneously converted into zeolite adsorbents. The processes conditions and the characteristics of the mesoporous aluminosilicate generated are studied. The second year: based on the results from the first year study, the surface characteristics is modified with organic functional groups such as amino group, to facilitate the removal of arsenate and chromate from wastewater. Effects of modifications on both the pore structure and surface chemistry are studied. The adsorption by the functionalized mesoporous aluminosilicate adsorbents in related to target toxic oxyanions in wastewater are characterized. The preparation of mesoporous aluminosilicate adsorbents using sludge and incinerator residues as starting materials is a novel process, not only cost-effective but also recycling-beneficial. And the wastes-synthesized mesoporous aluminosilicate adsorbents has outperforming characteristics in adsorption and a wide range of potential applications. This study expects the results can be applied to the wastewater treatment process in industries from which sludges can be recycled and synthesized into a high-efficient adsorbent. And again, these functional adsorbents can be applied in the air and water treatment units. This preparation of the functional environmental-purifying composite from waste sludges and incinerator ashes is a novel technology not only recycling oriented, cost-effective but also environmental-benificial. |
