もみ殻灰を用いたゼオライト硬化体の合成

抄録

Rice husk contains 13∼29mass% inorganic constituents. The main component is silica which constitutes 87∼97mass% of them. A lot of rice husk ash is discharged as a by-product of thermal power generation. The ash contains a high proportion of SiO₂ (94.3mass%) with a small percent of carbon. The SiO₂ fired at a low temperature is amorphous, water-soluble and high-reactive. The ash in the present study is produced by combustion at a low temperature around 800°C in thermal power plant. The ash is not effectively utilized for recycling and disposed as soil. By the way, zeolite is attracting attention as an environment improvement material, and high uniformity synthetic zeolite are in demand. For the effective use of the ash, in the present study, bulky consolidated zeolite A has been synthesized using the ash. Bulky consolidated zeolite A was synthesized with the ash and sodium aluminate. The consolidated zeolite A obtained at a heat-treatment temperature of 70°C. The microstructure of consolidated zeolite A was controlled by foam formation technique, because zeolite A has several functions depending on pore size in the consolidated body. In addition to intrinsic pore in the consolidated zeolite body, pores with diameter from tens to hundreds (m were uniformly formed in the zeolite body by adding Si and surface acting agent during preparation of the precursor. The consolidated zeolite A exhibited good humidity conditioning characteristics.