The invention relates to a method for producing an aerogel using a sol-gel process, in which first a lyogel is formed from at least two precursor sols and the lyogel is then converted to an aerogel.

Provided is a method for purifying a waste solvent by removing carbon dioxide contained in a waste solvent derived from supercritical waste liquid generated after supercritical drying by a decompression process, and removing ammonia by a multi-stage distillation process to obtain a solvent of high purity, which can be reused in producing silica aerogel or a silica aerogel blanket.

The hybrid aerogel of the present invention includes an aerogel having a network structure created by bonded secondary particles of a metal oxide with pores formed among the secondary particles; and nano-size hollow particles of 30 nm or more and 360 nm or less in outer diameter and mixed into the aerogel. Gas flow paths formed by the communication of the pores in the aerogel are blocked by the shells of the nano-size hollow particles. Provided is a solid thermal insulation material with highly thermal insulation performance comparable to vacuum insulation and not collapsing even when atmospheric pressure acts thereon.

The present invention relates to a method of preparing a high hydrophobic silica aerogel having a low tap density and a hydrophobic silica aerogel prepared thereby. The method of preparing a hydrophobic silica aerogel according to the present invention may have good productivity and economic efficiency, because preparation time is reduced by simultaneously performing surface modification and solvent substitution in a single step, and may control a degree of hydrophobicity of the prepared silica aerogel by controlling a surface modification reaction by including a step of adding ammonium hydroxide. Thus, a hydrophobic silica aerogel having excellent physical properties, such as tap density and specific surface area, as well as high hydrophobicity obtained by controlling the degree of hydrophobicity may be prepared.

A nanoscale ionic material composition, such as but not limited to a nanoscale ionic solid material composition, a nanoscale ionic gel material composition or a nanoscale ionic liquid material composition, may be prepared using an acid/base reaction directly between: (1) one of an acid functional and a base functional inorganic metal oxide nanoparticle core absent an organofunctional corona; and (2) a corresponding complementary one of a basic and acidic functional organic polymer material canopy. Desirably, the nanoscale ionic material composition is formed absent an intervening chemical functionalization process step with respect to the inorganic metal oxide nanoparticle core that provides the corona, such as but not limited to a silane coupling agent chemical functionalization process step with respect to the inorganic metal oxide nanoparticle core to provide the corona.

A nanoscale ionic material composition, such as but not limited to a nanoscale ionic solid material composition, a nanoscale ionic gel material composition or a nanoscale ionic liquid material composition, may be prepared using an acid/base reaction directly between: (1) one of an acid functional and a base functional inorganic metal oxide nanoparticle core absent an organofunctional corona; and (2) a corresponding complementary one of a basic and acidic functional organic polymer material canopy. Desirably, the nanoscale ionic material composition is formed absent an intervening chemical functionalization process step with respect to the inorganic metal oxide nanoparticle core that provides the corona, such as but not limited to a silane coupling agent chemical functionalization process step with respect to the inorganic metal oxide nanoparticle core to provide the corona.

The present invention provides a process for the preparation of phosphor aerogel of uniform size having high porosity, low density; high thermal insulation and high luminescence, which is useful for various applications like lighting, display, sensing and other applications.

More specifically, the present invention provides a simple and versatile process for the formation of monolithic gel, at room temperature, which on further drying at supercritical temperature and pressure result in dry aerogel. Further, annealing under mild reduced atmosphere from 1000°-1400° C. not only retains the porous network with uniform size particles but also crystallizes to form a phosphor aerogel having brightest luminescence with bulk density as low as 100 kg m-3, and strong enough to support a weight much higher than its own weight.

Provided are a method for preparing a hydrophobic silica aerogel by the combined use of a first surface modifier and a second surface modifier, and a hydrophobic silica aerogel prepared by using the method. A hydrophobic silica aerogel having excellent physical properties and pore characteristics as well as a high degree of hydrophobicity may be prepared with high efficiency by the preparation method according to the present invention.

The present invention is directed to a process for preparing an inorganic aerogel, the process comprising the steps of providing a composition (I) suitable to form an inorganic gel with a gelation time t.sub.G, spraying the composition (I) into supercritical carbon dioxide at a spraying time t.sub.S to obtain gel particles, and drying the gel particles obtained in step (ii) by supercritical liquid extraction, wherein the ratio t.sub.S:t.sub.G is in the range of from 0.2 to 0.99. The present invention further is directed to the inorganic aerogel as such as well as the use of the inorganic aerogel according to the invention in particular for medical and pharmaceutical applications or for thermal insulation.

The present invention is directed to a process for preparing an inorganic aerogel, the process comprising the steps of providing a composition (I) suitable to form an inorganic gel with a gelation time t.sub.G, spraying the composition (I) into supercritical carbon dioxide at a spraying time t.sub.S to obtain gel particles, and drying the gel particles obtained in step (ii) by supercritical liquid extraction, wherein the ratio t.sub.S:t.sub.G is in the range of from 0.2 to 0.99. The present invention further is directed to the inorganic aerogel as such as well as the use of the inorganic aerogel according to the invention in particular for medical and pharmaceutical applications or for thermal insulation.