A stabilization process for an arsenic solution comprising thiosulfates, the process comprising: acidifying the arsenic solution to decompose the thiosulfates, to yield an acidified solution; oxidizing the acidified solution to oxidize residual As.sup.3+ to As.sup.5+ and reduced sulfur species to sulfates, to yield a slurry comprising elemental sulfur; separating elemental sulfur from the slurry to yield a liquid; oxidizing the liquid to oxidize residual reduced sulfur species, to yield an oxidized solution; and forming a stable arsenic compound from the oxidized solution.

The present invention provides a method for removing pentavalent antimony contaminants in water without adding a DC power supply and also provides a fuel cell capable of removing the pentavalent antimony contaminants in water by utilizing self-generated electric energy. A technical solution of the present invention is as follows: waste water is pumped into a reactor for reaction after a pH value of the waste water containing the pentavalent antimony contaminants adjusted to 3-6.5; the inside of a reactor is an anaerobic environment; and an iron anode is arranged in the reactor, a through hole is formed in a side wall of the reactor, a cathode for reducing oxygen by electrons and protons sealed and inlaid in the through hole, and a resistor is connected between the iron anode and the cathode in series. The present invention is suitable for a water treatment technology.

A composite exhibiting a thermoelectric effect is provided. The composite comprises a metal sulphosalt, an electrically conductive polymer, and fibres. A method of making a composite material is also provided, comprising mixing the components. The three components work together to provide a low-cost thermoelectric composite that utilises readily available materials. A friction material and a thermoelectric device comprising the composite of the invention are also discussed. Preferably a copper sulphosalt is used, such as tetrahedrite. Preferably man-made vitreous fibres and a binder are used.

A method for producing antimony trisulfide can inexpensively produce antimony trisulfide that has a relatively low content of lead, arsenic, and crystalline silica (i.e., impurities). The method includes charging a reaction vessel with an antimony trioxide powder and sulfur, and heating the inside of the reaction vessel to react antimony trioxide with sulfur. Since antimony trioxide is obtained by volatilization-oxidation refining, antimony trioxide has a small particle size and a large specific surface area, and exhibits good reactivity, and high-purity antimony trioxide having a low content of impurities (e.g., lead, arsenic, and crystalline silica) is easily available. It is possible to inexpensively produce antimony trisulfide having a low content of impurities by utilizing high-purity antimony trioxide as a raw material.

The present invention relates to a catalyst system for oxidation of o-xylene and/or naphthalene to phthalic anhydride (PA), comprising a plurality of catalyst zones arranged in succession in the reaction tube, which has been produced using antimony trioxide consisting predominantly of the senarmontite modification of which all primary crystallites have a size of less than 200 nm. The present invention further relates to a process for gas phase oxidation, in which a gas stream comprising at least one hydrocarbon and molecular oxygen is passed through a catalyst system which comprises a plurality of catalyst zones arranged in succession in the reaction tube and which has been produced using an antimony trioxide consisting predominantly of the senarmontite modification with a median primary crystallite size of less than 200 nm.

A process is provided for separation of at least one metal sulfide from a mixed sulfide concentrate. The process includes: subjecting the mixed sulfide concentrate to flotation in which at least one sulfide including antimony, arsenic and a first metal is floated and at least one sulfide including a second metal is depressed. The flotation yields a first metal concentrate having the at least one sulfide including antimony, arsenic and the first metal and a second metal concentrate having the at least one sulfide including the second metal. The first metal concentrate is leached to yield a further concentrate and a leach solution. The further concentrate includes the first metal and the leach solution includes soluble antimony and soluble arsenic. The process further includes oxidizing the leach solution to yield an antimony precipitate and an arsenic solution, and forming a stable arsenic compound from the arsenic solution.

There is disclosed a tin-containing metal oxide nanoparticle, which has an index of dispersion degree less than 7 and a narrow particle size distribution which is defined as steepness ratio less than 3. There is disclosed dispersion, paint, shielding film and their glass products which comprise the said nanoparticles. Besides, there are also disclosed processes of making the tin-containing metal oxide nanoparticle and their dispersion. The tin-containing metal oxide nanoparticles and their dispersion disclosed herein may be applied on the window glass of houses, buildings, vehicles, ships, etc. There is provided an excellent function of infrared blocking with highly transparent, and to achieve sunlight controlling and thermal radiation controlling.

There is disclosed a tin-containing metal oxide nanoparticle, which has an index of dispersion degree less than 7 and a narrow particle size distribution which is defined as steepness ratio less than 3. There is disclosed dispersion, paint, shielding film and their glass products which comprise the said nanoparticles. Besides, there are also disclosed processes of making the tin-containing metal oxide nanoparticle and their dispersion. The tin-containing metal oxide nanoparticles and their dispersion disclosed herein may be applied on the window glass of houses, buildings, vehicles, ships, etc. There is provided an excellent function of infrared blocking with highly transparent, and to achieve sunlight controlling and thermal radiation controlling.

Embodiments of the present disclosure are directed to a doped tin oxide. The doped tin oxide includes a tin oxide and at least one oxide of a doping element. The doping element includes at least one of vanadium and molybdenum. The doped tin oxide includes an amount of the tin oxide ranging from 90 mol % to 99 mol %, and an amount of the at least one oxide ranging from 1 mol % to 10 mol %.

The present invention relates to a catalyst system for oxidation of o-xylene and/or naphthalene to phthalic anhydride (PA), comprising a plurality of catalyst zones arranged in succession in the reaction tube, which have been produced using antimony trioxide comprising a noticeable proportion of senarmontite wherein some of the primary crystallites have a size of less than 200 nm. The present invention further relates to a process for gas phase oxidation, in which a gas stream comprising at least one hydrocarbon and molecular oxygen is passed through a catalyst system which comprises a plurality of catalyst zones arranged in succession in the reaction tube and which has been produced using an antimony trioxide comprising a noticeable proportion of senarmontite wherein some of the primary crystallites have a size of less than 200 nm.