Seeking information related to acetonitrile

Acetonitrile is primarily obtained as a by-product of acrylonitrile production facilities. Due to the economic crisis, these facilities operate at reduced capacity, resulting in a decrease in acetonitrile production and an imbalance between supply and demand. As a result of manipulations in the supply chain, its price soared to over 100,000 units for a period of time; however, such exorbitant profits are not the norm. Last edited by paraquat on 2009-4-10 14:08]

I’m not sure whether you need information on its chemical production or its physical properties; could you please provide details on its properties first? Acetonitrile 【Physical and Chemical Properties】 Acetonitrile (also known as ethanenitrile, CH3CN), also referred to as methyl cyanide, has a molecular weight of 41.05. Its melting point is (-43±2)°C, and its boiling point is 81.6°C. At normal temperature and pressure, it appears as a colorless liquid. Its density is 0.7768 g/cm3 at 25/4°C. It has an aromatic odor, but prolonged exposure to this smell can lead to olfactory fatigue, making it difficult to detect its presence. It is volatile; at 24°C, its vapor pressure is 11.53 kPa, the density of its vapor is 1.42 g/L. The saturated concentration in air is 9.6% (at 20°C and 101.31 kPa), and the density of saturated air is 1.04 g/L ； It is soluble in water, and it also mixes easily with ethanol, ether, propane, chloroform, carbon tetrachloride, vinyl chloride, etc. Its aqueous solution is unstable and can hydrolyze to acetic acid and ammonia ； Acetonitrile releases HCN when heated. 【Occupational exposure】 Acetonitrile is produced by heating a mixture of acetamide and glacial acetic acid. It is an important industrial solvent, primarily used as a medium in organic synthesis (such as phenylacetone, 1-naphthoic acid, thiamine, etc.), and it can also be used as an extractant for fatty acids and as a denaturant for alcohols. Poisoning can occur during the production process due to contact with its liquids or vapors. 【Clinical manifestations】 Acute occupational acetonitrile poisoning is not rare, with numerous reports available both domestically and internationally. 　　Acetonitrile vapor is mildly irritating; therefore, at high concentrations, it can cause certain degree of irritation in the upper respiratory tract. Compared to hydrogen cyanide, although acetonitrile also causes symptoms such as nausea, vomiting, abdominal pain, diarrhea, chest tightness, chest pain, fatigue, and weakness, and in severe cases can lead to respiratory depression, low blood pressure, coma, and convulsions, its onset is slower, with an incubation period of usually more than 4 hours ； The condition is also less severe than that caused by hydrogen cyanide, and it rarely leads to sudden death ； Both the pulse rate and heart rate slow down, respiration is also slower, the complexion is often pale, and it often leads to kidney damage manifestations such as proteinuria. The toxicity of acetonitrile is related not only to the CN- released in the body, but also the effects of acetonitrile itself and its metabolic products such as thiocyanate, which cannot be ignored. There are currently no clinical products for chronic acetonitrile poisoning. 【Diagnosis and Differential Diagnosis】 The diagnosis of acute acetonitrile poisoning is primarily based on a reliable history of high-level exposure to acetonitrile as well as clinical symptoms; similar symptoms appearing in individuals who were exposed together serve as a significant indicator ； Timely measurement of the levels of CN-, SCN-, and acetonitrile in plasma is indicative; they serve as biomarkers of acetonitrile exposure, but they cannot indicate whether poisoning has occurred or what its severity is. In acute acetonitrile poisoning, it is necessary to distinguish it from poisoning by other industrial toxins present at the workplace, such as organic solvents and asphyxiating gases, as well as from conditions like cerebrovascular accidents and diabetic coma. 【Treatment】 The treatment for acute acetonitrile poisoning can refer to the information provided in the section on hydrogen cyanide, although the dose of methemoglobin-forming agents can be reduced by half. When sodium thiosulfate is used, high-molecular-weight methemoglobin-forming agents with a slower effect such as p-aminophenylpyruvic acid (PAPP) can be administered early; 1 tablet is taken orally each time, and it can be repeated every 4 hours. On the following day, only sodium thiosulfate is needed for maintenance ； After 2 days, the dosage of sodium thiosulfate can also be halved, and the medication should be discontinued after 3 to 5 days. Since acetonitrile is itself toxic, while administering cyanide antidotes, it is particularly important to carry out symptomatic supportive treatment, to maintain the function of the heart, lungs, and brain, and to administer appropriate fluid replacement and diuretics in order to accelerate the elimination of the toxin and reduce kidney damage. In terms of production: There are many methods for producing acetone, among which the main industrial method is the ammonolysis of acetic acid ； Acetylene amination method and propylene ammoxidation by-product method, etc. 　　1. The ammoniation acetic acid method uses acetic acid ； Using ammonia as a raw material, acetonitrile is synthesized in one step under the action of an aluminum oxide catalyst at a temperature of 360–420°C. The reaction mixture is then subjected to water absorption and distillation to yield the final product. Raw material consumption quota: Acetic acid (98%) 1763 kg/t ； Liquid ammonia (99.5%) 691 kg/t. 　　2. The acetylene amination method uses acetylene ； Acetonitrile is synthesized in one step using ammonia as a raw material and an aluminum oxide catalyst at a temperature of 500–600°C. Raw material consumption quota: 10,231 m3 of acetylene ； Liquid ammonia (99.4%) 1007 kg/t. 　　3. The propylene amin oxidation by-product method uses propylene ； When acrylonitrile is synthesized from ammonia and air using a catalyst, acetonitrile is produced as a by-product. 25-100 kg of acetonitrile can be produced as a by-product per ton of acrylonitrile. 　　4. Obtained by the dehydration of acetamide and phosphorus pentoxide. 　　5. Obtained by the reaction of dimethyl sulfate with sodium cyanide. This post was last edited by dst339 on 2009-4-10 14:23]

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I use chromatographically pure acetonitrile to prepare the mobile phase

It seems there are no companies that produce acetonitrile separately; its production indeed relies mainly on the separation of by-products from acrylonitrile production facilities. There was an abnormal price increase for acetonitrile some time ago; the chromatographically pure acetonitrile used in HPLC saw its price soar to over a hundred yuan, and this is indeed closely related to the production process of acrylonitrile! However, I heard recently that the price of acetonitrile has started to drop.

Our factory specializes in solvent recovery, focusing on waste acetonitrile and the recycling of acetonitrile. It is now possible to recover acetonitrile solvent by recycling various types of waste acetonitrile. If you have acetonitrile, please get in touch with me. Phone: 18560330110, Mr. Zhao. The company’s services include: 1) the purchase of acetonitrile mother liquor at a fair price; 2) providing acetonitrile processing services; 3) purchasing solvents from factories along with all necessary procedures. Our company operates on a year-round basis to recycle acetonitrile solvents of various concentrations. We offer generous compensation to intermediaries. Contact person: Zhao Dongchu, phone: 18560330110, QQ: 905080534, WeChat: 18560330110. We sincerely welcome your calls. If you need assistance with acetonitrile recovery, I’m available to work together on this. Of course, your company can also carry out the recovery process on its own; we can offer some technical support. Please contact me if needed