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Chemicals from Olefin Hydrocarbons
Published in James G. Speight, Handbook of Petrochemical Processes, 2019
Ethoxylates are the products of ethoxylation reactions in which ethylene oxide is added to a substrate. The most widely used reaction relative to the petrochemical industry is alkoxylation which involves the addition of epoxides to substrates. Typically, esters (R1CO2R2) are formed directly by the addition of acids to olefin derivatives, mercaptans by the addition of hydrogen sulfide to olefin derivatives, sulfides by the addition of mercaptans to olefin derivatives, and amines by the addition of ammonia and other amines to olefin derivatives.
Improve Bastnaesite Flotation via Synergistic Effect of Octyl Hydroxamic Acid and Octyl Phenol Ethoxylated Surfactants
Published in Mineral Processing and Extractive Metallurgy Review, 2023
Xu Wu, Yiwen Hu, Sultan Ahmed Khoso, Zhao Cao
To observe the aggregation phenomena, a 150 mL suspension involving 0.5 wt.% bastnaesites with a particle size of −15 μm was transferred into a 200 mL glass beaker and stirred at room temperature with a magnetic stirrer at 500 rpm. The slurry was stabilized at pH 9 with HCl or NaOH solution. Then, after 4 min of regulating, the desired dosages of octyl hydroxamic acid and octyl phenol ethoxylation were added to the slurry. After adjusting the pH to 9 again, another 4 min was used to stabilize the growth of the aggregates. After the desired slurry was successfully prepared, a small amount of mineral suspension was placed onto the center of a glass slide and gently covered with a coverslip on the top. Direct observations of aggregate structures were performed with an optical microscope (Axio Scope A1, Carl Zeiss AG). Images of the observed bastnaesite samples were captured immediately.
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
Ethylene oxide is an important raw material used in the manufacture of chemical derivatives that are the basis for major consumer goods in virtually all industrialized countries. More than half of the ethylene oxide produced worldwide is employed in the manufacture of mono-ethylene glycol. Other important derivatives of ethylene oxide include di-ethylene glycol, tri-ethylene glycol, poly(ethylene) glycols, ethylene glycol ethers, ethanol-amines, and ethoxylation products of fatty alcohols, fatty amines, alkyl phenols, cellulose and poly(propylene) glycol. Only a small proportion (0.05%) of the annual production of ethylene oxide is utilized directly in the gaseous form as a sterilizing agent, fumigant and insecticide. This agent is well known as a sterilant of drugs, hospital equipment, disposable and reusable medical items. Most human exposure is occupational, although some exposure occurs from air pollution and tobacco smoking.
Interactions between a Small Bubble and a Greater Solid Particle during the Flotation Process
Published in Mineral Processing and Extractive Metallurgy Review, 2019
Pavlína Basařová, Jan Zawala, Mária Zedníková
Another significant factor is the surfactant’s molecular structure. Surfactants that are based on ethylene oxide are the most common form of nonionic surfactants. This type is produced through the ethoxylation of chains of fatty alcohol. The most common forms possess 12 carbons within the alkyl chain. For larger and other complex molecules, a barrier of adsorption that prevents other molecules’ adhesion and that contains branched molecules captured on phase interface should be expected (Eastoe and Dalton 2000). Such a barrier is brought into existence within dilute solutions. Then, it rises with increasing concentrations and changes again near the CMC concentration. Such a barrier’s existence is usually associated with some steric restraints upon molecules in the interface’s proximity since molecules ought to be orientated correctly. An unsuitable orientation has the potential to result in molecules diffusing back into the bulk instead of adsorbing. Transport of these molecules is low and therefore the influence they have upon the TPC line expansion’s velocity can be quite low (Basarova et al. 2016).