Perchlorate is poorly abundant on earth, except combined with sodium nitrate mineral in some specific arid areas. Natural perchlorate is extracted to produce fertilisers. Perchlorate is intensively used in the formulation of explosive propellant for various explosives and weapons. To cover this strategic need, perchlorate is produced industrially. Perchlorate Molecular structure of perchlorate. Perchlorate is…
Introduction Ammonia (NH₃) is a colourless, low molecular weight gas with the chemical formula NH₃ (See figure 1). It has a pungent smell, often associated with strong household cleaners. Ammonia (NH₃) is lighter than air but can be easily condensed to a liquid due to strong hydrogen bonding between the ammonia molecules (hydrogen bonding is…
Where does nickel come from? Pure nickel (Ni) is a silvery-white metal that is rarely found as a pure metal in the earth’s crust because it will oxidise when it comes into contact with oxygen. Pure nickel can be found in the interiors of larger nickel–iron meteorites that were not exposed to oxygen when outside the earth’s atmosphere or in ultramafic rocks. Nickel is…
Introduction Mercury species exists in various forms: elemental (or metallic); inorganic (e.g. mercuric chloride); and organic mercury (e.g., methyl- and ethylmercury), which all have different toxic effects. Mercury poisoning can result from exposure to water-soluble forms of mercury (such as mercuric chloride or methylmercury), inhalation of mercury vapour, or by ingesting any form of mercury.…
Where does lead come from? Lead is most commonly found as lead (II) sulphide (PbS) in the mineral galenite. Cerussite (tin-lead ore), with the chemical composition lead (II) carbonate (PbCO₃), is a secondary mineral of lead formed by the chemical reaction of carbonated water with galena. A third important source of lead is anglesite (lead…
The “rotten egg” odour in some water supplies is caused by sulphide in water. Sulphide can be treated using oxidation techniques, the goal being to convert the sulphide to high oxidation state species such as sulphate to eliminate the taste and odour concerns. Traditional oxidation techniques such as ozone and chlorine can be used but…
Introduction Arsine (AsH₃) is an extremely toxic gas that is generated upon exposure of arsenic-containing ores to acids. It is also a by-product of refining of non-ferrous metals. Arsine is used extensively in the manufacture of microchips, solid-state lasers and for the synthesis of organoarsenic compounds. Arsine (AsH₃) is a colourless, flammable, non-irritating toxic gas…
Introduction Phosphine is the compound with the chemical formula PH₃. Phosphine (PH₃) is used as an intermediate in organophosphorus chemistry and as a dopant in the semiconductor industry. Phosphine (PH₃) is alsowidely used as a fumigant (for example, in the tobacco industry) that does not leave residues on the stored product, and for pest control.…
Introduction The properties of land fill leachate varies widely in composition depended on different factors such as the age of the landfill and the type of waste that is stored in the landfill. Water percolating through the waste will promote the micobiological decomposition of organics. This digestion process rapidily use up any available oxygen creating…
The Problem Liquid Sucrose or sugar produced from beet or, occasionally, cane sugar can contain different taste or colour compounds. To combat this, a granular activated carbon process was developed using mobile filters to produce colourless and transparent liquid sucrose solutions with a neutral, sweet taste, free from any off-flavours. Application Information Liquid sucrose stream…
