Zinc is a lustrous bluish-white metal. It is found in group IIb of the periodic table. It is brittle and crystalline at ordinary temperatures, but it becomes ductile and malleable when heated between 110°C and 150°C. It is a fairly reactive metal that will combine with oxygen and other non-metals, and will react with dilute acids to release hydrogen.
It is used principally for galvanizing iron, more than 50% of metallic zinc goes into galvanizing steel, but is also important in the preparation of certain alloys.
It is used for the negative plates in some electric batteries and for roofing and gutters in building construction.
Zinc is the primary metal used in die casting in the automobile industry.
As a pigment zinc is used in plastics, cosmetics, photocopier paper, wallpaper, printing inks etc, while in rubber production its role is to act as a catalyst during manufacture and as a heat disperser in the final product.
Zinc in the environment
Zinc is a very common substance that occurs naturally. Many foodstuffs contain certain concentrations of zinc. Drinking water also contains certain amounts of zinc, which may be higher when it is stored in metal tanks. Industrial sources or toxic waste sites may cause the zinc amounts in drinking water to reach levels that can cause health problems.
Zinc occurs naturally in air, water and soil. Most zinc is added during industrial activities, such as mining, coal and waste combustion and steel processing.
The main zinc mining areas are Canada, Russia, Australia, USA and Peru. World production exceeds 7 million tonnes a year and commercially exploitable reserves exceed 100 million tonnes.
Health effects of zinc
Zinc is a trace element that is essential for human health. When people absorb too little zinc they can experience a loss of appetite, decreased sense of taste and smell, slow wound healing and skin sores. Zinc-shortages can even cause birth defects.
Although humans can handle proportionally large concentrations of zinc, too much zinc can still cause eminent health problems. .
In the work place environment zinc contagion can lead to a flu-like condition known as metal fever. This condition will pass after two days and is caused by over sensitivity.
Zinc can be a danger to unborn and newborn children. When their mothers have absorbed large concentrations of zinc the children may be exposed to it through blood or milk of their mothers.
Effects of zinc on the Environment
The world's zinc production is still rising. This basically means that more and more zinc ends up in the environment.
Water is polluted with zinc, due to the presence of large quantities of zinc in the wastewater of industrial plants. This wastewater is not purified satisfactory. One of the consequences is that rivers are depositing zinc-polluted sludge on their banks. Zinc may also increase the acidity of waters.
2- Zinc Concentrate
RioALTO offers zinc concentrate with a majority zinc base component. Preparation of zinc concentrate typically involves the removal of water from an zinc solution.
RioALTO specializes in producing high purity Zinc Concentrate with the smallest possible average grain sizes for use in preparation of pressed and bonded sputtering targets and in Chemical Vapor Deposition (CVD) and Physical Vapor Deposition (PVD) processes including Thermal and Electron Beam (E-Beam) Evaporation, Low Temperature Organic Evaporation, Atomic Layer Deposition (ALD), Metallic-Organic and Chemical Vapor Deposition (MOCVD). Zinc concentrate is similar to powder in that it is made up of minute, dry particles of pure substance.
Our standard Concentrate particle sizes average in the range of - 325 mesh, - 100 mesh, 10-50 microns and submicron (< 1 micron).
RioALTO produces different grades , including Mil Spec (military grade); ACS, Reagent and Technical Grade; Food, Agricultural and Pharmaceutical Grade; Optical Grade, USP and EP/BP (European Pharmacopoeia/British Pharmacopoeia)and follows applicable ASTM testing standards. We also produce Zinc as rod, ingot, pieces, pellets, disc, granules, wire, and in compound forms, such as oxide.
Nonferrous metals are specified for structural applications requiring reduced weight, higher strength, nonmagnetic properties, higher melting points, or resistance to chemical and atmospheric corrosion. They are also specified for electrical and electronic applications.
3- Zinc Oxide
Zinc oxide is an inorganic compound with the formula ZnO. ZnO is a white powder that is insoluble in water, and it is widely used as an additive in numerous materials and products including rubbers, plastics, ceramics, glass, cement, lubricants, paints, ointments, adhesives, sealants, pigments, foods, batteries, ferrites, fire retardants, and first-aid tapes.
It occurs naturally as the mineral zincite, but most zinc oxide is produced synthetically. It is also widely used to treat a variety of other skin conditions, in products such as baby powder and barrier creams to treat diaper rashes, calamine cream, anti-dandruff shampoos, and antiseptic ointments.
Copper is reddish, malleable and ductile metallic element with excellent thermal and electrical conductive qualities. It is a very important industrial material and is used in the electrical, electronics, transportation and construction industries.
Because of its properties, singularly or in combination, of high ductility, malleability, and thermal and electrical conductivity, and its resistance to corrosion, copper has become a major industrial metal, ranking third after iron and aluminum in terms of quantities consumed.
Copper is one of the materials which contribute strongly to economic growth in Europe. This material is very significant to the economy because it has many different application in a wide range of key economical sectors.
Although copper is relatively easy to recycle, the recycling rate has been static for some time. All-in-all, the EU Recycling Input Rate increased to 40% in 2008, up from 38% in 2007. The unique qualities of copper make it difficult to substitute. That said, copper use in a number of non-electrical construction applications can be replaced by aluminium or non-metal materials. This is a seizable proportion of existing use.Aluminum substitutes are used for copper in power cables, electrical equipment, automobile radiators, and cooling and refrigeration tube; titanium and steel are used in heat exchangers; optical fiber substitutes for copper in telecommunications applications; and plastics substitute for copper in water pipe, drain pipe, and plumbing fixtures.
Aluminium is a silvery-white metal, the 13 element in the periodic table. One surprising fact about aluminium is that it's the most widespread metal on Earth, making up more than 8% of the Earth's core mass. It's also the third most common chemical element on our planet after oxygen and silicon.
At the same time, because it easily binds with other elements, pure aluminium does not occur in nature. This is the reason that people learned about it relatively recently. Formally aluminium was produced for the first time in 1824 and it took people another fifty years to learn to produce it on an industrial scale.
The most common form of aluminium found in nature is aluminium sulphates. These are minerals that combine two sulphuric acids: one based on an alkaline metal (lithium, sodium, potassium rubidium or caesium) and one based on a metal from the third group of the periodic table, primarily aluminium.
Aluminium sulphates are used to this day to clean water, for cooking, in medicine, in cosmetology, in the chemical industry and in other sectors. By the way, aluminium got its name from aluminium sulphates which in Latin were called alumen.
Alumina, also called aluminum oxide, synthetically produced aluminum oxide, Al2O3, a white or nearly colourless crystalline substance that is used as a starting material for the smelting of aluminum metal. It also serves as the raw material for a broad range of advanced ceramic products and as an active agent in chemical processing.
In alumina solidified without chemical sintering aids, pores are trapped within the grains, …
Alumina is made from bauxite, a naturally occurring ore containing variable amounts of hydrous (water-containing) aluminum oxides. Free Al2O3 occurs in nature as the mineral corundum and its gemstone forms, sapphire and ruby; these can be produced synthetically from alumina and in fact are occasionally referred to as alumina, but the term is more properly limited to the material employed in aluminum metallurgy, industrial ceramics, and chemical processing. Translucent alumina. With the use of magnesia as a sintering aid, pores diffuse from the material …Some alumina is still produced by melting bauxite in an electric furnace, in a process devised for the abrasives industry early in the 20th century, but most is now extracted from bauxite through the Bayer process, which was developed for the aluminum industry in 1888. In the Bayer process bauxite is crushed, mixed in a solution of sodium hydroxide, and seeded with crystals to precipitate aluminum hydroxide. The hydroxide is heated in a kiln in order to drive off the water and produce several grades of granular or powdery alumina, including activated alumina, smelter-grade alumina, and calcined alumina.
Activated alumina is a porous, granular substance that is used as a substrate for catalysts and as an adsorbent for removing water from gases and liquids. Smelter-grade alumina accounts for 90 percent of all alumina produced; it is transported to aluminum plants, where it is electrolyzed into aluminum metal. Calcined alumina is made into a variety of ceramic products, including spark-plug insulators, integrated-circuit packages, bone and dental implants, laboratory ware, sandpaper grits and grinding wheels, and refractory linings for industrial furnaces. These products exhibit the properties for which alumina is well known, including low electric conductivity, resistance to chemical attack, high strength, extreme hardness (9 on the Mohs hardness scale, the highest rating being 10), and high melting point (approximately 2,050 °C, or 3,700 °F).
The toughness of alumina can be improved by the addition of zirconia particles or silicon-carbide whiskers, making it suitable for industrial cutting tools. Also, the normally opaque material can be made translucent by adding small amounts of magnesia. Translucent alumina is employed as the gas container in high-pressure sodium-vapour streetlamps.