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Thermal-Catalytic Incineration of Waste Gases
Published in Maria da Graça Carvalho, Woodrow A. Fiveland, F. C. Lockwood, Christos Papadopoulos, Combustion Technologies for a Clean Environment, 2021
Teresa Banaszak, Ryszard Miller, Anita Zieba
The neutralization (oxidation) of toxic additives in the waste gas usually proceeds as a complex, multistage reaction with a number of secondary organic waste products. It is therefore important to organize the neutralization process so as to limit the creation of the products of incomplete oxidation, especially when they are toxic. A comparison of the capabilities of the catalytic and thermal-catalytic processes to limit the creation of incomplete combustion products was conducted using the waste gas containing ethyl alcohol (Figs. 4 and 5). Acetaldehyde is a product of the partial oxidation of ethyl alcohol. In order to evaluate the efficiency of the neutralization of the waste gas an additional parameter was introduced, called the process selectivity, towards the complete oxidation of the substrate (Straszko, 1979).
List of Chemical Substances
Published in T.S.S. Dikshith, and Safety, 2016
Exposures to acetaldehyde liquids and vapors for a prolonged period in work areas cause irritation to the eyes, skin, upper respiratory passages, and bronchi. Continued exposure is known to damage the corneal epithelium, dermatitis, photophobia, a foreign body sensation, and persistent lacrimation or discharge of tears. Acetaldehyde causes bronchitis and a reduction in the number of pulmonary macrophages. The severity of lung damage increases with the build up of fluid in the lungs (pulmonary edema), and respiratory distress in the worker. Occupational workers exposed to high concentrations of acetaldehyde suffer coughing, pulmonary edema, necrosis, photophobia, a foreign body sensation, damage to the nasal mucosa and trachea, and persistent lacrimation.
Organic Air Pollutants
Published in Stanley E. Manahan, Environmental Chemistry, 2022
Acetaldehyde is a widely produced organic chemical used in the manufacture of acetic acid, plastics, and raw materials. Acrolein is used as a raw material to make acrylic acid and as a biocide and is responsible for the odor produced by overheated cooking oil owing to the breakdown of glycerol in the oil. Approximately 1 billion kg of acetone are produced each year as a solvent and for applications in the rubber, leather, and plastics industries. Methylethyl ketone is employed as a low-boiling solvent for coatings and adhesives and for the synthesis of other chemicals.
Overview of biological mechanisms of human carcinogens
Published in Journal of Toxicology and Environmental Health, Part B, 2019
Nicholas Birkett, Mustafa Al-Zoughool, Michael Bird, Robert A. Baan, Jan Zielinski, Daniel Krewski
Ethanol is metabolized to acetaldehyde by three major pathways: the alcohol dehydrogenase (ADH) pathway, the microsomal ethanol oxidizing cytochrome P450 (CYP) pathway, and the catalase-H2O2 system. Acetaldehyde, to which many deleterious effects of ethanol can be attributed, is oxidized to acetate primarily by aldehyde dehydrogenases (ALDHs). Over the past decade, epidemiological evidence of enhanced cancer risks among heterozygous carriers of the inactive ALDH enzyme has become much stronger, in particular for esophageal cancer: practically all studies conducted in East-Asian populations who consumed alcoholic beverages show significantly increased odds ratios for carriers of the inactive ALDH allele. In addition, several studies have demonstrated associations between the polymorphism of ADH1B and upper aero-digestive tract cancers, which have been explained either by more active ADH producing more acetaldehyde or by less active ALDH causing prolonged exposure to lower levels of ethanol-derived acetaldehyde. These data imply that acetaldehyde is the key compound in the development of cancers of the esophagus and other upper aero-digestive tract cancers associated with alcoholic beverage consumption