Provided are a positive electrode active material for a secondary battery, in which, since the positive electrode active material includes a lithium-metal oxide having high-temperature stability and a metal oxide on a surface of a particle and a surface side in the particle, there is no concern about gas generation, because the occurrence of cracks on the surface of the active material is prevented during charge and discharge, and high-temperature storage stability and life characteristics may be improved when the positive electrode active material is used in the battery, and a secondary battery including the same.

In a method for recovering active metals of a lithium secondary battery according to an embodiment, a cathode active material mixture is collected from the cathode of the lithium secondary battery, the cathode active material mixture is reduced by a reducing reaction to prepare a preliminary precursor mixture, an aqueous lithium precursor solution is formed from the preliminary precursor mixture, and an aluminum-containing material is removed from the aqueous lithium precursor solution with an aluminum removing resin.

In a method for recovering active metals of a lithium secondary battery according to an embodiment, a cathode active material mixture is collected from the cathode of the lithium secondary battery, the cathode active material mixture is reduced by a reducing reaction to prepare a preliminary precursor mixture, an aqueous lithium precursor solution is formed from the preliminary precursor mixture, and an aluminum-containing material is removed from the aqueous lithium precursor solution with an aluminum removing resin.

Provided is a spherical alumina powder which, when incorporated into resins in a high concentration, enables a resin composition to have low viscosity and which has reduced viscosity increase in the resin composition over time after surface treatment of the spherical alumina powder. The spherical alumina powder has an alkyl group(s) derived from a silane compound(s) on its surface, and is characterized in that an intensity ratio {I (CH.sub.3)/I (CH.sub.2)} of a peak (29605 cm.sup.1) associated with asymmetric vibration of CH.sub.3 to a peak (29255 cm.sup.1) associated with asymmetric vibration of CH.sub.2 in the alkyl group(s) of the silane compound(s) in the same spectral data obtained by infrared spectroscopic analysis measurement is 0.2 or more and less than 2.0.

A plate-like alumina powder production method of the present invention comprises placing a transition alumina and a fluoride in a container such that the transition alumina and the fluoride do not come into contact with each other and then performing heat treatment to obtain a plate-like -alumina powder. The transition alumina is preferably at least one selected from the group consisting of gibbsite, boehmite, and -alumina. It is preferable that the amount of the fluoride used is set such that the percentage ration of F in the fluoride to the transition alumina is 0.017% by mass or more. The container preferably has a volume such that a value obtained by dividing the mass of F in the fluoride by the volume of the container is 6.510.sup.5 g/cm.sup.3 or more. The heat treatment is preferably performed at the temperature of 750 to 1,650 C.

For depolymerization of a cured epoxy resin material, used is a composition including a transition metal salt or a transition metal oxide containing a transition metal element (metal element that belongs to Groups 3-12 in the Periodic Table). In the reaction solvent, an oxidation occurs by the medium of the transition metal element so that the cured epoxy resin material may be depolymerized and decomposed. In this manner, it is possible to carry out depolymerization of a cured epoxy resin material at a temperature of 200 C., specifically 100 C. or lower very simply and rapidly, and to reduce the processing cost and energy requirement.

A superhydrophobic surface can be formed by contacting an article with a suspension of fluorinated boehmite particles to leave a film of the fluorinated boehmite particles after removal of the suspending fluid. The film can be transparent or the film can be translucent or opaque. When the film is translucent or opaque, the film can render the surface superoleophobic.

A particulate material having a body including a first phase having at least about 70 wt % alumina for a total weight of the first phase, and a second phase comprising phosphorus, wherein the body includes at least about 0.1 wt % of the second phase for the total weight of the body, and wherein the second phase has an average grain size of not greater than about 1 micron.

A furnace may include a furnace muffle that can accommodate relatively larger workpieces than other furnaces. The furnace muffle may include a cover that includes one or more sets of plates. The plates may be configured to prevent sag during extended runtimes while still enabling the furnace to reach a temperature (e.g., a temperature between 1590 C. and 1650 C.) for sintering a workpiece. In some examples, the cover may include a first set of plates of a first material (e.g., a first alumina refractory material) and a second set of plates of a second material (e.g., a second alumina refractory material). The second material may have greater thermal conductivity than the first material. Accordingly, plates of the second set may be located in higher temperature zones of the furnace to enable efficient heat transfer from heater elements through the furnace muffle to a contact plate where a workpiece is heated.

A furnace may include a furnace muffle that can accommodate relatively larger workpieces than other furnaces. The furnace muffle may include a cover that includes one or more sets of plates. The plates may be configured to prevent sag during extended runtimes while still enabling the furnace to reach a temperature (e.g., a temperature between 1590 C. and 1650 C.) for sintering a workpiece. In some examples, the cover may include a first set of plates of a first material (e.g., a first alumina refractory material) and a second set of plates of a second material (e.g., a second alumina refractory material). The second material may have greater thermal conductivity than the first material. Accordingly, plates of the second set may be located in higher temperature zones of the furnace to enable efficient heat transfer from heater elements through the furnace muffle to a contact plate where a workpiece is heated.