Chemical uses, lime

Before going further, let us clarify the various common names of limestone and lime. The following is a summaiy of the nomenclature and the chemicals referred to. Industrial chemists quite often use the common names for these substances rather than the chemically descriptive names. 

Precipitation refers to the process of adding one or more chemical reagents to water so that dissolved contaminants are transformed (precipitated) into insoluble solids (precipitates) (US EPA, 2002b, 17). The precipitates can then be collected and removed from the water by filtration, flotation, centrifugation, or other methods. For arsenic in water, precipitation typically involves reactions between arsenic oxyanions and dissolved cations. A common example is the precipitation of calcium arsenates from the addition of lime to a wastewater containing dissolved As(V). 

On sensory examination of wines, Lachman was a master. He abhorred still wines of excess carbon dioxide. He writes of first, second, and third tastes. (But some of these are surely odors, not tastes.) Blending is considered the most difficult branch of the handling of wines. It should, he says, be assisted by chemical analysis. The judge must be in condition. He should be able to detect any blemish, and tell whether a wine has been corrected by use of lime, chalk, or salt. This tells us a good deal about the poor quality of wines of the period, as does Bioletti s letter (12). 

As shown by the various chemical reactions above, the chemicals soda ash and lime may be used for the removal of hardness caused by calcium and magnesium. Thus, the lime-soda process is used. This process, as mentioned, uses lime (CaO) and soda ash (Na2C03). As the name of the process implies, two possible sets of chemical reactions are involved the reactions of lime and the reactions of soda ash. To understand more fully what really is happening in the process, it is important to discuss these chemical reactions. Let us begin by discussing the lime reactions. 

Professor Dickinson wrote all the reports, usually classified as SECRET. After I obtained SECRET security clearance, he allowed me to read some of the reports, and the professor explained to all of us the science and chemistry of what went on when a poison gas flowed through a gas mask. The gas might remain unaltered and be adsorbed by cracks in the charcoal particles, or it might undergo chemical reaction with water, added soda lime or added copper oxide in the charcoal. It was not correct to say that a charcoal did or did not stop a war gas. After a heavy enough exposure to any gas, any charcoal would eventually become saturated, and the gas would... 

Chemicals used to treat raw water and improve its quality include corrosion inhibitors, pH adjusters and alkalinity, and hardness-controlling agents. The commonly used water treatment chemicals are soda ash, sodium bicarbonate, sodium hydroxide (caustic soda) plus carbon dioxide, lime, alkaline media filters, combinations such as limestone slurry, carbon dioxide, sodium hydroxide. All US water utilities are required to always monitor the water quality by an analysis of treated water. The samples for analysis are taken at regular time intervals and at different locations spread out over the system. 

Lime was and still is used in soil stabilization, road building, chemical manufacture, the tanning process, and the purification of water, whitewashing buildings, treating animal hides and leather, and for plaster and mortar. The US National Lime Association tends to think that lime is "the versatile chemical."... 

Markush structure chemical structures in generic form, very often used in patents. They contain a general structure formula and text, which specifies the generic groups. The Markush structure is named after the chemist Eugene Markush who used this way of describing related compounds 1924 in the US patent 1,506,316 for the first lime. 

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