Industrial solvents carbon disulfide

The industrial solvent carbon disulfide can be made from the reaction between methane and hydrogen sulfide at elevated temperatures using the following reaction gas-phase reaction ... 

Carbon disulfide is a volatile organic solvent, used mainly as a starting material in rayon manufacture in the viscose process. It was important historically in the cold vulcanization of rubber. Although no longer used in this form, carbon disulfide is still a major industrial precursor in rubber industry chemical synthesis and has a number of other industrial applications. Carbon disulfide is also widely used as a solvent in a variety of laboratory settings. Carbon disulfide is a metabolite of the drug disulfiram (see pp 186) and is a spontaneous breakdown by-product of the pesticide metam sodium. 

C14-0119. Both CCI4 (carbon tetrachloride) and CS2 (carbon disulfide) are liquids used as solvents in special industrial applications, (a) Using data Irom Appendix D, calculate A 77 ° and A G ° for combustion... 

So-called peripheral neuropathies can result from excessive exposure to certain industrial solvents such as carbon disulfide (CS2, used in the rubber and rayon industries) and hexane (CgHn, once used in certain glues and cleaning fluids). Over-exposure to acrylamide, an important industrial chemical, and chronic alcohol abuse can also induce this effect. As the name implies, it involves attack of the chemical on and damage to axonal portions of neurons. Typical symptoms of peripheral neuropathies include weakness or numbness in the limbs, which are more or less reversible depending upon the specific agent and the intensity of exposure. 

Carbon disulfide is used in the manufacture of rayon, cellophane, electronic vacuum tubes, and xanthogenates. It is used to make carbon tetrachloride. It also is used as an industrial solvent and as an analytical solvent. Because of its low response to GC-FID, it is used widely in air analysis of organic compounds. 

Nonmetallic neurotoxins are frequently used in industry in manufacturing of chemicals and resins or as solvents. Some examples are hydrogen sulfide (which paralyzes specifically the nervous centers that control respiratory movement), carbon disulfide, -hexane, methyl -butyl ketone, and acrylamide. Exposure to all of these substances may occur through inhalation of vapors. In addition, carbondisufide and acrylamide may enter the system by dermal absorption. -Hexane and methyl -butyl ketone are not toxic by themselves but are activated by cytochrome P-450 to the neurotoxic hexanedione (CH3COCH2CH2COCH3). 

Summary Ammonium picramate is the ammonium salt of picramic acid, and is made by reducing picric acid with ammonium bisulfide and ammonia solution. Sulfur is a by-product and must be removed with carbon disulfide. The sulfur/carbon disulfide solution can be distilled to recover the carbon disulfide solvent, and recover the sulfur by-product. The ammonium picramate is recovered by filtration. Commercial Industrial note Part or parts of this laboratory process may be protected by international, and/or commercial/industrial processes. Before using this process to legally manufacture the mentioned explosive, with intent to sell, consult any protected commercial or industrial processes related to, similar to, or additional to, the process discussed in this procedure. This process may be used to legally prepare the mentioned explosive for laboratory, educational, or research purposes. 

Attempts should be made to use alternate solvents for industrial processes. Solvents that pose and cause the most serious risk to human health should be replaced by less hazardous ones. If this is not possible, at least the work conditions and exposure to solvents should be adjusted to avoid or minimize the health risk. This may be achieved, for example, by using a closed process. Among solvents, the most hazardous ones identified are benzene, carbon disulfide, and carbon tetrachloride. 

Thirty-nine different dithiocarbamates have been efficiently prepared through a one-pot reaction of an aliphatic primary or secondary amine, carbon disulfide and an alkyl halide (Figure 2.16). " Typically, all reagents were liquids and the mixture slowly solidified upon reaction. Therefore, although the reaction does not use solvents, the reagents are probably acting as the solvent in this procedure. Additionally, the reactions were quenched with water and extracted with ethyl acetate, so solvent was used. Nevertheless, this is an excellent synthetic method for the preparation of S-alkyl dithiocarbamates, which are useful compounds for the pharmaceutical and agrochemical industries. 

Carbon disulfide is an important industrial solvent for the extraction of oils and waxes. In organic chemistry, it is widely used as a solvent for Friedel-Crafts reactions. Carbon disulfide functions as an electrophilic reagent. It is more susceptible than carbon dioxide to nucleophilic attack as the energy required to convert C=S to C-S (188 kJmol 1) is much less than required for the analogous conversion of C=0 to C-0 (305 kJmol 1). Carbon disulfide (1) thus undergoes nucleophilic additions with alcohols and phenols to yield the corresponding xanthates (2) (the xanthate reaction) (Scheme 2)... 

Many organosulfur compounds have major industrial uses. For instance, carbon disulfide and DMSO are important commercial solvents and dithiocarbamates are used in the rubber industry as vulcanisation accelerators long chain alkanesulfonic or arenesulfonic acids are important synthetic detergents. Xanthates are used in the manufacture of rayon (see Chapter 8, p. 135) and cellophane, and many commercial dyes contain sulfonic acid groups (see Introduction, p. 5). Sulfamic acid derivatives such as saccharin (see Chapter 9, p. 162) acesulfame potassium (see Introduction, p. 5) and cydamates (see Chapter 9, p. 162) are valuable artificial sweeteners. 

So-called peripheral neuropathies can result from excessive exposures to certain industrial solvents such as carbon disulfide (CS2, used in the rubber and rayon industries) and hexane (CgH, once used... 

Its fat, rubber, and metal solvent properties have made carbon disulfide highly suitable for a variety of other continuing industrial applications including the following vulcanization and manufacture of... 

In the food industry, carbon disulfide has been used to protect fresh fruit from insects and fungus during shipping, in adhesives for food packaging, and in the solvent extraction of growth inhibitors (Timmerman 1978). 

The primary disposition of carbon disulfide in the environment is related to its use as an industrial solvent and chemical intermediate. Releases from industrial processes are almost exclusively to the atmosphere. Releases of the compound to surface waters and soils are expected to partition rapidly to the atmosphere through volatilization. Hydrolysis and biodegradation do not appear to be important processes in determining the environmental fate of carbon disulfide. It has been detected at generally low levels in ambient air, surface water, groundwater, drinking water, food products, and human milk. Concentrations in environmental media are greatest near source areas (e g., industrial point sources, oceans and marshes, volcanoes). 

Solvent manufacturing is an important part of the economy. Annual productions of carbon disulfide and xylene range in the millions of tons (Arlien-Soborg 1992 Snyder and Andrews 1996). The annual production of 1,1,1-trichloroethane, found in 250 household chemicals, exceeds 700 million tons (Kurt and Buffler 1995). With this level of production, a significant number of workers are at risk for exposure. More than 450,000 workers have exposure risks to per-chloroethylene or tetrachloroethylene in the dry cleaning industry (White et al. 1990). Various sources indicate possible exposures of 3.5 million workers to trichloroethylene and 140,000 potentially... 

Moscato et al. (1997) studied concentrations of benzene, toluene and xylene in a hospital in Italy located far away from industrial and high-traffic pollution. They undertook fixed-site and area monitoring using the 130-Radiello, radial-diffusive type cartridge filled with 530 mg of activated charcoal and an exposure period of 8 h. For analysis the charcoal was solvent desorbed with carbon disulfide and analysed by GC/FID using a Vocol 30 m/0.53 mm ID/3 pm film thickness fused silica capillary column (Supelco, USA). Indoor benzene concentrations were low (<1 pg/m ), mean toluene concentrations ranged from 1.44 pg/m (summer) to 6.04 pg/m (autumn) and xylenes ranged from 10.78 pg/m- (summer) to 21.48 pg/m (winter). 

Ethanol is a colorless, clear liquid with a characteristic, pleasant odor. It is miscible in all proportions with water and readily miscible with many organic solvents (e.g., ethers, hydrocarbons, acids, esters, ketones, carbon disulfide, glycols, and other alcohols). Ethanol dissolves castor oil, cellulose nitrate with a low nitrate content, polar resins, and polymers. Ethanol in combination with aromatic compounds dissolves cellulose acetate. Mixtures of ethanol, aromatic hydrocarbons, and water are good solvents for some polyamides. Ethanol is extensively used in the chemical and pharmaceutical industries. It is employed as a raw material for many chemical syntheses (e.g., esterification, as an ethylating agent, and reaction medium). Ethanol is an excellent solvent, diluent, and extracting agent for fats, oils, paints, and... 

Produced annually in ton quantities (2). They are industrial objectives for which the riedel-Crafts strategy has frequently been used. From the point of view of pollution prevention, there are a number of reasons why alternatives must be considered. The Friedel-Cr ts pathway involves corrosive and air sensitive acid chlorides, Lewis acids such as duminum chloride, stannic chloride or titanium tetrachloride and solvents such as nitrobenzene, carbon disulfide, carbon tetrachloride or methylene chloride (3). Althou some research directed toward minimizing the amount of Lewis acid needed for the Friedel-Crafts reaction has been reported, this modification requires elevated temperatures (4). Friedel-Crafts reactions conducted with acidic resins nave also been reported. This research appears promising but is in the early stages (5). Obviously, an attractive alternative to the traditional Friedel-Crafts reaction would have an impact on pollution prevention. 

Carbon disulfide, CS2, is an important industrial solvent for waxes, greases, celluloses, and other nonpolar substances. It is a colorless, volatile liquid (bp 46.3 °C). The vapor is very poisonous and highly flammable. 

The US pulp and paper industry operates over 550 facilities which employ over 200,000 people. Total shipments are 60 billion with an additional 80 billion in converted products. Several proeesses eontribute to the emission of solvents. These include chemical pulping kraft process (terpenes, alcohols, methanol, acetone, chloroform), bleaching (acetone, dichloromethane, chloroform, methyl ethyl ketone, carbon disulfide, chloromethane, and trichloroethane), wastewater treatment (terpenes, alcohols, methanol, acetone, chloroform and methyl ethyl ketone), and evaporators in chemical recovery systems (alcohols and terpenes). 

Tables 14.25.1 and 14.25.2 provide data on the reported releases and transfers of solvents by the US rubber and plastics industry. These industries contribute small amounts of VOC which are in the range of0.00001-0.00005 kg VOC/kg of processed rubber. It was the ninth largest contributor to releases and transfers of all US industries. Dichloromethane, toluene, carbon disulfide, methyl ethyl ketone, methanol, 1,1,1-trichloroethane, hexane, methyl isobutyl ketone, and xylene are emitted in very large quantities.

Methanol + xylene + toluene constitute over half (52.6%) of all released and transferred solvents by the analyzed industries. This is in fact good news because neither of the five most frequently released and transferred solvents is considered to have carcinogenic effect. But four (methanol, xylene, ethylene glycol, and toluene) contribute to the pollution of lower atmosphere and xylene and toluene cause formation of ozone in lower atmosphere by which it may affect the respiratory system. Carbon disulfide causes formation of hydroxyl radicals which have relatively long half-life (a few days) and thus participate in a variety of photochemical processes. All five solvents are relatively easy to biodegrade. 

This chapter deals merely with exposure to common organic solvents which are used in large quantities to dissolve fats, resins, and other materials. Very dangerous chemicals, such as benzene, which are no more used as solvents due to their toxic properties, will not be discussed even though they may have had even extensive uses as solvents earlier and even though those may be still important chemicals as petroleum components or as intermediates for other chemicals. Also, solvents with very specialized uses, such as carbon disulfide the use of which is practically limited to viscose rayon industry and laboratories, are only... 

Carbon disulfide was the first solvent studied and had adverse effects observed by Delpech in 1863. Neuropsychiatric abnormalities were described 13 years later by Eulenberg in workers in the rubber and viscose rayon industries. A Finnish psychologist, Helen Hanninen tested 100 carbon disulfide exposed workers in 1970,50 were poisoned, 50 exposed and compared them to 50 unexposed.She found intelligence, tasks of attention, motor skill vigilance and memory were impaired in clinically poisoned and exposed men compared to unexposed. Digit symbol substitution from the Wechsler s scale showed the most effect of exposure. Additional studies of spray painters in the 1970 s and compared to computer augmented tomography (CT) scans of the brain and function tests. Symptomatic painters after 20 years or more of exposure had brain atrophy associated with impairment."" ... 

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