Manufacture of Glycerine from Petrochemical and Carbohydrate Raw Materials
Eric Jungermann, Norman O.V. Sonntag in Glycerine, 2018
High-temperature chlorination of propylene gas is accomplished by preheating to about 400°C and passing previously vaporized liquid chlorine through a water heater, at a ratio of 4:1 propylenexhlorine. The inlet chlorine jets receive the halogen at 60 psi and 20°C. The propylene/chlorine mixture reacts in a steel tube type reactor. The high exothermic nature of the chlorination requires insulation of the reactor for temperature control; ordinarily the reactants are between 400–500°C for an estimated time of only 2–3 seconds at 15 psig. Figure 4.2 shows a schematic outline of the chlorination and the succeeding process steps. Chlorine utilization is over 99%. Two reactors are run alternately to afford an opportunity for cleanouts, which are required about twice a month. Although the chemical reaction shows only allyl chloride as the product, this amounts to only about 80% of the chlorinated products. There are also chloropropenes, mixed dichlorides, trichlorides, and heavier residues. The largest of the organic byproducts consists of about 15% cis- and trans-1,3-dichIoropropenes and 1,2-dichloropropane. Hydrogen chloride is the largest of the inorganic byproducts.
Chemistry
Stephen P. Coburn in The Chemistry and Metabolism of 4′-Deoxypyridoxine, 2018
In a typical run, 600 mf of acetone was distilled directly into a 1000- mf round bottom flask containing 45 g pyridoxine hydrochloride. After cooling to 0°C in brine, dry hydrogen chloride was bubbled through a gas diffusion tube with stirring until a 15 to 17% solution was obtained. Stirring was continued for 30 min in the ice bath and for one hour at room temperature. The reaction can be monitored by chromatography and/or ultraviolet spectroscopy to verify that the phenol group is blocked. After standing overnight at 4°C, 400 ml of cold, dry ether was added to the cold suspension and the precipitate of isopropylidenepyridoxine hydrochloride was collected by filtration, washed with cold ether, and dried at 65°C for 2 hr (yield 50.4 g [94%]; M.P. 210 to 212°C [decomposition]).
The Toxic Environment and Its Medical Implications with Special Emphasis on Smoke Inhalation
Jacob Loke in Pathophysiology and Treatment of Inhalation Injuries, 2020
Although carbon monoxide plays an important role in morbidity and mortality of fire victims, the increasing hazard and toxicity from the fumes and gases due to plastic fires on the lungs have been recognized (Cornish and Abar, 1969; Dyer and Esch, 1976; Alarie, 1985; Lowry et al. 1985a). Mortality has been observed in smoke inhalation fire victims without burns, in which there is severe chemical lung injury, but the carboxyhemoglobin level is within the sublethal range (Lowry et al., 1985b). Similar findings were observed in laboratory animals (Kishitani, 1971). This is the result of toxic gases and fumes such as hydrogen chloride, hydrogen cyanide, and other toxic gases. Thermal degradation of polyvinyl chloride, which is present in many plastic polymers, releases hydrogen chloride, a hydroscopic substance, which in combination with water vapor, hydrochloric acid forms an aerosol. Hydrochloric acid also has corrosive properties capable of causing significant irritation and a damaging effect on the mucous membranes of the eyes, nose, and respiratory tract. It should be noted that in the thermal degradation of polyvinyl chloride, neither chlorine gas or phosgene is produced (Sorenson, 1976). In a recent study of low-energy controlled fires of combined wood, paper, clothing, polyvinyl chloride, and other synthetic materials, free radicals (yet to be identified) were formed, and investigators suggested that these free radicals had the equivalent oxidative power of chlorine gas (Lowry et al., 1985b). The signs and symptoms of chlorine gas inhalation depend on the different levels of chlorine gas exposure (Table 6). Whether these free radicals produce similar signs and symptoms induced by chlorine gas remains to be elucidated.
Post-treatment with a heat shock protein 90 inhibitor prevents chronic lung injury and pulmonary fibrosis, following acute exposure of mice to HCl
Published in Experimental Lung Research, 2020
Margarita Marinova, Pavel Solopov, Christiana Dimitropoulou, Ruben M. L. Colunga Biancatelli, John D. Catravas
Acute exposure to hydrogen chloride causes various pathologies, including respiratory distress syndromes.1,2 Hydrogen chloride vapors (fumes) are heavier than air and have been identified as a main source of irritation, airway inflammation and asphyxiation in poorly ventilated or low-lying areas. It is highly water-soluble and, in contact with water, forms hydrochloric acid, HCl. Upon inhalation, it is quickly deposited as HCl on the mucus membranes of the nose, pharynx and lower respiratory tract. Single exposures to high doses can result in symptoms of acute airway obstruction such as cough, chest tightness and pulmonary edema.3,4 Clinical signs, including airway hyper-responsiveness, bronchospasm as well as pneumonitis had been documented.5,6 More severely affected individuals were reported to develop persistent lung injuries including reactive airways dysfunction syndrome (RADS), an asthma-like condition that may persist for months to even years.3,4,7–9
Synthesis and antitumor activity of novel 2, 3-didithiocarbamate substituted naphthoquinones as inhibitors of pyruvate kinase M2 isoform
Published in Journal of Enzyme Inhibition and Medicinal Chemistry, 2018
Xianling Ning, Hailong Qi, Ridong Li, Yan Jin, Michael A. McNutt, Yuxin Yin
The 1,4-naphthaquinone (1) (1 g, 6.3 mmol) in glacial acetic acid (20 ml) was taken in a 100-ml round-bottomed flask, and 36% aqueous formaldehyde (6 ml) was added. The reaction solution was cooled in ice water. Dry hydrogen chloride passed in for 2 h. The solution became red, then being kept at room temperature for 48 h. The reaction mixture was poured on ice and extracted with ethyl acetate. The combined organic fractions were washed with brine, dried (Na2SO4) and concentrated under reduced pressure. Purification of the crude residue by column chromatography (petroleum ether/ethyl acetate) afforded the compound 2 (yellow solid). The yield of this reaction was 68.9%. 1H NMR (400 MHz, CDCl3) δ 8.18–8.20 (m, 2H, ArH), 7.81–7.83 (m, 2H, ArH), 4.72 (s, 4H, 2CH2Cl).
Acute exposure of mice to hydrochloric acid leads to the development of chronic lung injury and pulmonary fibrosis
Published in Inhalation Toxicology, 2019
Margarita Marinova, Pavel Solopov, Christiana Dimitropoulou, Ruben M. L. Colunga Biancatelli, John D. Catravas
Hydrochloric acid (HCl), also known as muriatic acid, is one of the world’s most abundant industrial chemicals with numerous applications in oil and gas production, as a cleaning agent, as well as in the metal industry and mining (Dow-Chemical 1988; Austin and Glowacki 1989; Occidental-Chemical 1990). As the world demand for HCl is increasing every year, the potential for accidental exposures is getting greater (Energy.Environment.Economy 2012; OOSKANews 2012; NLTimes 2015). Unlike long-term workplace exposures, accidental spills and leaks are characterized by short-term, high-level exposures and can result in symptoms of acute airway obstruction. Types of acute exposure most commonly reported are inhalation of hydrogen chloride and/or HCl fumes (Kuligowski 2018). Because hydrogen chloride is highly soluble in water, it can easily form HCl upon contact with eyes, nose, and regions of the upper respiratory tract. Deeper penetration into the pulmonary tract can occur at higher doses. HCl is highly irritating to the entire respiratory tract, causing bronchitis, pulmonary edema, pneumonitis, and at higher doses even death (Bingham et al. 2001).
Related Knowledge Centers
- Atom
- Chemical Compound
- Diatomic Molecule
- Hydronium
- Chemical Formula
- Hydrochloric Acid
- Hydrogen
- Chlorine
- Chemical Polarity
- Partial Charge