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i am a QC/R&D executive dealing with analytical chemistry. We need to update more about the instrumentation and other relevant areas.

Carbitol cellosolve in industry
PHYSICAL AND CHEMICAL PROPERTIES PHYSICAL STATE	clear liquid MELTING POINT 	-76 C BOILING POINT	192 - 202 C SPECIFIC GRAVITY 	0.999 SOLUBILITY IN WATER	miscible pH VAPOR DENSITY 	4.64 AUTOIGNITION 	204 C NFPA RATINGS	Health: 1 Flammability: 1 Reactivity: 0 REFRACTIVE INDEX FLASH POINT	93 C STABILITY	Stable under ordinary conditions. Hygroscopic.

PRODUCT IDENTIFICATION CAS NO	111-90-0

EINECS NO.	203-919-7 FORMULA	C2H5OCH2CH2OCH2CH2OH MOL WT. 134.17	H.S. CODE TOXICITY SYNONYMS	carbitol cellosolve; Diglycol Monoethyl Ether; 2-(2-Ethoxyethoxy) ethanol; Ethyl digol; Ethyl Carbitol; Ethyl Digol; Ethyl Diglycol; Ethyl Dioxitol; Ethyl Oxitol Glycol Ether;

GENERAL DESCRIPTION & APPLICATIONS Glycol: any of a class of organic chemicals characterized by having separate two hydroxyl (-OH) groups, contribute to high water solubility, hygroscopicity and reactivity with many organic compounds, on usually linear and aliphatic carbon chain. The general formula is CnH2n(OH)2 or (CH2)n(OH)2. The wider meaning names include diols, dihydric alcohols, and dihydroxy alcohols. Polyethylene glycols and polypropylene glycols are sometimes called polyglycols which are derived by polymerization of ethylene oxide and propylene oxide respectively. Polyethylene glycols are water-soluble at all molecular weights, but polypropylene glycols become increasingly less water-soluble at high molecular weights. Ethylene glycol, HOCH2CH2OH, is the simplest member of the glycol family. Mono-, di- and triethylene glycols are the first three members of a homologous series of dihydroxy alcohols. They are colourless, essentially odourless stable liquids with low viscosities and high boiling points. Ethylene glycol is a colourless, odourless, involatile and hygroscopic liquid with a sweet taste. It is somewhat viscous liquid; miscible with water; boiling point 198 C, melting point 13 C; soluble in ethanol, acetone, acetic acid, glycerine, pyridine, aldehydes; slightly soluble in ether; insoluble in oil, fat, hydrocarbones. It is prepared commercially by oxidation of ethylene at high temperature in the presence of silver oxide catalyst, followed by hydration of ethylene oxide to yield mono-, with di-, tri-, and tetraethylene glycols as co-products. The yields of ethylene glycol are depend on pH conditions. The acid-catalyzed condition in the presence of excess water provides the highest yield of monoethylene glycol. Because of its low freezing point, involatility and low corrosive activity, it is widely used in mixtures of automobile antifreeze and engine-cooling liquids. Ethylene glycol has become increasingly important in the plastics industry for the manufacture of polyester fibers and resins, including polyethylene terephthalate, which is used to make plastic bottles for soft drinks (PET bottles). MEG is the raw material in the production of polyester fiber, PET resins, alkyd, and unsaturated polyester. Diethylene glycol, CH2OHCH2OCH2CH2OH, is similar in properties to MEG, but with a higher boiling point, viscosity, and specific gravity. Diethylene glycol is used in the manufacture of unsaturated polyester resins, polyurethanes and plasticizers. It is a water-soluble liquid; boiling point 245 C; soluble in many organic solvents. It is used as a humectant in the tobacco industry and in the treatment of corks, glue, paper and cellophane. Diethylene glycol (DEG) is derived as a co-product with ethylene glycol and triethylene glycol. The industry generally operates to maximize MEG production. Ethylene glycol is by far the largest volume of the glycol products in a variety of applications. Availability of DEG will depend on demand for derivatives of the primary product, ethylene glycol, rather than on DEG market requirements. Triethylene glycol, HO(C2H4O)3H, is a colourless, odourless, non-volatile, and hygroscopic liquid. It is characterised by two hydroxyl groups along with two ether linkages, which contribute to its high water solubility, hygroscopicity, solvent properties and reactivity with many organic compounds. DEG is used in the synthesis of morpholine and 1,4-dioxane. TEG is displacing diethylene glycol in many of these applications on account of its lower toxicity. TEG finds use as a vinyl plasticizer, as an intermediate in the manufacture of polyester resins and polyols, and as a solvent in many miscellaneous applications. Triethylene glycol (TEG) is derived as a coproduct in the manufacture of ethylene glycol from ethylene oxide, and from "on-purpose" TEG production using diethylene glycol. Some capacities are based on total capacity for ethylene glycols. The main uses for TEG depend upon its hygroscopic properties. Air conditioning systems use TEG as dehumidifiers and, when volatilized, as an air disinfectant for bacteria and virus control. Glycols, having high boiling point and affinity for water, are employed as liquid desiccant for the dehydration of natural gas. The dehydration means the removal of water vapor in refinery tower so that dry hydrocarbon gases can exit from the top of the tower. There are wide range of glycol ethers which have bifunctional nature of ether and alcohol. cellosolves are monoether derivatives of ethylene glycol. They are excellent solvents, having solvent properties of both ethers and alcohols. Glycol family products are versatile compounds used in the fields include; •	Anti-freezing and anti-icing additive •	Intermediate in polymer production and chemical reaction •	Solvent or plasticizer for plastic, lacquer, paint and varnish •	Hydraulic, brake, thermal exchange fluids and fuel additive •	Humidifying and plasticizing •	Dehydrating •	Coupling printing inks •	Textile conditioning •	Solvent for dyes in textile and leather finishing •	Agricultural formulation •	General purpose cleaners •	Explosives manufacture •	Electrolytic component •	Humectant •	Water-based coating •	Preservative, rust remover, and disinfectant Glycol ethers, with the combination of ether, alcohol and hydrocarbon chain in one molecule, provide versatile solvency characteristics with both polar and non-polar properties. The chemical structure of long hydrocarbon chain resist to solubility in water, while ether or alcohol groups introduce the promoted hydrophilic solubility performance. This surfactant-like structure provides the compatibility between water and a number of organic solvents, and the ability to couple unlike phases. Glycol ethers are characterized by their wide range of hydrophilic/hydrophobic balances. glycol ethers are used as diluents and levelling agents in the manufacture of paints and baking finishes. Glycol ether series are used in the manufacture of nitrocellulose and combination lacquers. They are used as an additive in brake fluid. They are formulated for dying textiles and leathers and for insecticides and herbicides. They provides performance in cleaners products with oil-water dispersions. They are used in printing industries as they have a slow evaporation rate. They are used as a fixative for perfumes, germicides, bactericides, insect repellents and antiseptic. They are used as an additive for jet fuel to prevent ice buildup. Thje term of cellosolve refers to ethylene glycol monoethyl ether or a group of glycol ether solvent as below. Glycol ether	Cellosolve	CAS RN Tris(ethylene glycol monobutyl ether) phosphate	Tributyl cellosolve phosphate	78-51-3 Ethylene glycol monoethyl ether acrylate	Cellosolve acrylate	106-74-1 Ethylene glycol isopropyl ether	Isopropyl cellosolve	109-59-1 Ethylene glycol monomethyl ether	Methyl cellosolve	109-86-4 Ethylene glycol monomethyl ether acetate	Methyl cellosolve acetate	110-49-6 Ethylene glycol dimethyl ether	Dimethyl cellosolve	110-71-4 Ethylene glycol monoethyl ether	Cellosolve	110-80-5 Ethylene glycol monomethyl ether oleate	Methyl cellosolve oleate	111-10-4 Ethylene glycol monoethyl ether acetate	Ethyl cellosolve acetate	111-15-9 Ethylene glycol monoallyl ether	Allyl cellosolve	111-45-5 Ethylene glycol monobutyl ether	Butyl cellosolve	111-76-2 Diethylene Glycol Monoethyl Ether 	Carbitol cellosolve	111-90-0 Ethylene glycol monobutyl ether acetate	Butyl cellosolve acetate	112-07-2 Ethylene glycol monohexyl ether	Hexyl cellosolve	112-25-4 Diethylene glycol monobutyl ether	Butyl carbitol	112-34-5 Ethylene glycol dibutyl ether	Dibutyl cellosolve	112-48-1 Bis(ethylene glycol monomethyl ether) phthalate	Dimethyl cellosolve phthalate	117-82-8 Bis(ethylene glycol monobutyl ether) phthalate	Dibutyl cellosolve phthalate	117-83-9 Ethylene glycol o,p-Dichlorophenyl ether	2,4-Dichlorophenyl cellosolve	120-67-2 Ethylene glycol monophenyl ether	Phenyl cellosolve	122-99-6 Ethylene glycol monomethyl ether acetylricinoleate	Methyl cellosolve acetylricinoleate	140-05-6 Bis(ethylene glycol monobutyl ether) adipate	Dibutyl cellosolve adipate	141-18-4 Ethylene glycol monobenzyl ether	Benzyl cellosolve	622-08-2 Ethylene glycol diethyl ether	Diethyl cellosolve	629-14-1 Ethylene glycol monopropyl ether	Propyl cellosolve	2807-30-9 Ethylene glycol monomethyl ether acrylate	Methyl cellosolve acrylate	3121-61-7 Ethylene glycol butyl ethyl ether	Butyl ethyl cellosolve	4413-13-2 Ethylene glycol monoisobutyl ether	Isobutyl cellosolve	4439-24-1 Ethyleneglycol 2-ethylbutyl ether	Ethylbutyl cellosolve	4468-93-3 Ethylene glycol monobutyl ether acrylate	Butyl cellosolve acrylate	7251-90-3 Ethylene glycol monoheptyl ether	Heptyl cellosolve	7409-44-1 Ethylene glycol monomethylpentyl ether	2-Methylpentyl cellosolve	10137-96-9 Ethylene glycol o,p-Dichlorophenyl methyl ether	2,4-Dichlorophenyl methyl cellosolve	10140-84-8 Ethylene glycol monobutyl ether phosphate	Butyl cellosolve phosphate	14260-98-1 Poly(cellosolve silicate)	Poly(cellosolve silicate)	37338-04-8 Ethylene glycol monophenyl ether acrylate	Phenyl cellosolve acrylate	48145-04-6 Ethylene glycol monoethyl ether oleate	Cellosolve oleate	68134-05-4 Ethylene glycol monobutyl ether sebacate	Butyl cellosolve sebacate	68186-66-3 Ethylene glycol monobutyl ether phosphate potassium salt	Butyl cellosolve, phosphate potassium salt	68389-63-9 Ethylene glycol monobutyl ether polyphosphate 	Butyl cellosolve polyphosphate	68514-82-9 Ethylene glycol monohexyl ether phosphate	Hexyl cellosolve phosphate	68814-14-2

Redox potentilas in biology
Redox (shorthand for oxidation-reduction) reactions describe all chemical reactions in which atoms have their oxidation number (oxidation state) changed. This can be either a simple redox process, such as the oxidation of carbon to yield carbon dioxide (CO2) or the reduction of carbon by hydrogen to yield methane (CH4), or a complex process such as the oxidation of sugar (C6H12O6) in the human body through a series of complex electron transfer processes. The term comes from the two concepts of reduction and oxidation. It can be explained in simple terms: •	Oxidation is the loss of electrons or an increase in oxidation state by a molecule, atom, or ion. •	Reduction is the gain of electrons or a decrease in oxidation state by a molecule, atom, or ion. Though sufficient for many purposes, these descriptions are not precisely correct. Oxidation and reduction properly refer to a change in oxidation number — the actual transfer of electrons may never occur. Thus, oxidation is better defined as an increase in oxidation number, and reduction as a decrease in oxidation number. In practice, the transfer of electrons will always cause a change in oxidation number, but there are many reactions that are classed as "redox" even though no electron transfer occurs (such as those involving covalent bonds). Non-redox reactions, which do not involve changes in formal charge, are known as metathesis reactions. Redox reactions in biology Top: ascorbic acid (reduced form of Vitamin C) Bottom: dehydroascorbic acid (oxidized form of Vitamin C) Many important biological processes involve redox reactions. Cellular respiration, for instance, is the oxidation of glucose (C6H12O6) to CO2 and the reduction of oxygen to water. The summary equation for cell respiration is: C6H12O6 + 6 O2 → 6 CO2 + 6 H2O The process of cell respiration also depends heavily on the reduction of NAD+ to NADH and the reverse reaction (the oxidation of NADH to NAD+). Photosynthesis and Cellular respiration are complementary but photosynthesis is not the reverse of the redox reaction in cell respiration: 6 CO2 + 6 H2O + light energy → C6H12O6 + 6 O2 Biological energy is frequently stored and released by means of redox reactions. Photosynthesis involves the reduction of carbon dioxide into sugars and the oxidation of water into molecular oxygen. The reverse reaction, respiration, oxidizes sugars to produce carbon dioxide and water. As intermediate steps, the reduced carbon compounds are used to reduce nicotinamide adenine dinucleotide (NAD+), which then contributes to the creation of a proton gradient, which drives the synthesis of adenosine triphosphate (ATP) and is maintained by the reduction of oxygen. In animal cells, mitochondria perform similar functions. See Membrane potential article. The term redox state is often used to describe the balance of NAD+/NADH and NADP+/NADPH in a biological system such as a cell or organ. The redox state is reflected in the balance of several sets of metabolites (e.g., lactate and pyruvate, beta-hydroxybutyrate and acetoacetate), whose interconversion is dependent on these ratios. An abnormal redox state can develop in a variety of deleterious situations, such as hypoxia, shock, and sepsis. Redox signaling involves the control of cellular processes by redox processes. Redox proteins and their genes must be co-located for redox regulation according to the CoRR hypothesis for the function of DNA in mitochondria and chloropl Redox proteins and their genes must be co-located for redox regulation according to the CoRR hypothesis for the function of DNA in mitochondria and chloroplasts. [edit] Redox cycling A wide variety of aromatic compounds are enzymatically reduced to form free radicals that contain one more electron than their parent compounds. In general, the electron donor is any of a wide variety of flavoenzymes and their coenzymes. Once formed, these anion free radicals reduce molecular oxygen to superoxide, and regenerate the unchanged parent compound. The net reaction is the oxidation of the flavoenzyme's coenzymes and the reduction of molecular oxygen to form superoxide. This catalytic behavior has been described as futile cycle or redox cycling. Examples of redox cycling-inducing molecules are the herbicide paraquat and other viologens and quinones such as menadione.