Identifying Pharmaceutical-Grade Essential Oils and Using Them Safely and Effectively in Integrative Medicine
Aruna Bakhru in Nutrition and Integrative Medicine, 2018
Notable Reagents Used in the Commercial Synthesis of Methyl Salicylate: Methanol is used to esterify salicylic acid and is considered toxic at levels greater than 80 mL, but poses problems including decreased vision and kidney failure at much lower concentrations.32Phenol is the beginning substrate for much of the methyl salicylate synthetically produced and is toxic even at vapor levels with a minimum lethal amount of 140 mg/kg.33Sulfuric acid is used for the acidification of the product and is one of the strongest and corrosive acids used in commercial production.
Glycerine Analysis
Eric Jungermann, Norman O.V. Sonntag in Glycerine, 2018
For glycerine samples that are basic to phenolphthalein in 10% aqueous solution: Two to 5 g of glycerine is ashed at 500°C. The ash, consisting of sodium oxide from sodium hydroxide, sodium carbonate, and sodium soaps is titrated with sulfuric acid and reported as “total alkalinity,” in units of % sodium oxide.Barium chloride is added to a fresh sample to precipitate carbonates and soaps, and an aliquot of the clear supernatant solution is titrated with hydrochloric acid. This gives the amount of sodium hydroxide in the sample, reported as “free caustic alkalinity,” in units of % sodium oxide.Another sample is neutralized with sulfuric acid. This converts carbonate to carbon dioxide, which is then removed by boiling. The sample is then titrated to a phenolphthalein endpoint to give the amount of soap present, expressed as “alkalinity combined with organic acids,” in units of % sodium oxide.Carbonate content is calculated by deducting hydroxide (2, above) and soap (from 3, above) from total alkalinity (1, above)
Chemistry
Stephen P. Coburn in The Chemistry and Metabolism of 4′-Deoxypyridoxine, 2018
The solution was heated at 90° C for six hours and finally brought to a boil for a few minutes. Barium sulfate was removed by filtration and a few drops of dilute sulfuric acid were added to the filtrate in order to precipitate any remaining barium ions. An excess of sulfuric acid should be avoided. The clear filtrate was treated with charcoal and evaporated to near dryness. The 4′-deoxypyridoxine hydrochloride was recrystallized from ethanol (yield: 45%; M.P. 264°C). It seems likely that the charcoal treatment may have contributed to the low yield reported for this step.
Biofilm diversity, structure and matrix seasonality in a full-scale cooling tower
Published in Biofouling, 2018
L. Di Gregorio, R. Congestri, V. Tandoi, T. R. Neu, S. Rossetti, F. Di Pippo
The cooling tower used in this study was a cross-flow tower from an oil refinery plant located in an eastern European country. Full details of the plant and all other operational details can be obtained by contacting the corresponding author. The cooling tower contained three cells and each cell was supplied with a ventilator. The unit had four pumps on the cooled water side (500 m3 h−1 each) and four pumps on warm water side (one is 720 m3 h−1, the other three were 500 m3 h−1). At the bottom of the cooling tower the sedimentation basins were located, which were open to the air and sunlight. Make-up water entered the cooling tower by a connection to the cooling tower basin. The make-up intake was controlled automatically by opening the intake valve according to the warm water suction pit level. Blow-down was regulated manually according to the conductivity value through the oil skimmers. Sodium hypochlorite, algicides, scale inhibitors (polymers) and biocide enhancers (surfactants and bio-dispersants) were dosed continuously to limit microbial fouling. Sodium hypochlorite was dosed to the outlet of the sedimentation basin, while chemicals were dosed into the back line to the tower basin. The water pH was adjusted to neutrality with sulphuric acid.
Extraction and derivatisation of active polysaccharides
Published in Journal of Enzyme Inhibition and Medicinal Chemistry, 2019
Yang Liu, Gangliang Huang
Concentrated sulphuric acid method. The method uses concentrated sulphuric acid as the source of sulphuric acid group, pyridine as the medium, and then chemical modification of polysaccharide residues. The advantages of this method are less toxicity and relatively stable conditions, while the disadvantage is that exothermic conditions can also exist in concentrated sulphuric acid reaction, which can carbonise polysaccharides. For example, Luan et al.23 used concentrated sulphuric acid method to sulphate polysaccharides from Schisandra chinensis leaves. The best experimental conditions were summarised by single-factor experiments: the reaction temperature and reaction time of 1.4 h at 3:1 and 0 °C. Finally, the substitution degree of sulphate in polysaccharide can reach 0.4597.
Chemical mismanagement and skin burns among hospitalized and outpatient department patients
Published in International Journal of Occupational Safety and Ergonomics, 2021
Salman Majeed, Mati Ur Rahman, Hammad Majeed, Sami Ur Rahman, Asif Hayat, Sandra D. Smith
The various acids, cleaning agents and detergents may cause chemical burns when their high-grade solutions are used, e.g., hydrochloric acid and bleach. In cleaning agents, low-grade sulfuric acid is used, which may still be the cause of severe skin burns. Acids were reported as the cause of both major and minor skin burns (as mentioned in Table 4); however, solvents/detergents and most of the reported alkalis were the causes of minor skin burns. Such chemicals may lead to fatal consequences, e.g., chemical poisoning and the victim’s death [26]. These results are consistent with the studies conducted by Xie et al. [8] and Ye et al. [25] in which the authors mentioned acids, followed by alkalis, as leading causes of chemical skin burns. Additionally, inflammation could be experienced which may damage the skin when chemicals get into contact with the human body [27]. Some alternative methods of treatments are also noted by different scholars to treat burn wounds, such as aloe vera, honey and bee pollen, and are noted to be helpful to facilitate granulation of the burn wound due to their anti-inflammatory, antiviral, antimicrobial, antifungal and immunostimulating properties [28–30].
Related Knowledge Centers
- Chemical Burn
- Oxygen
- Sulfur
- Sulfur Trioxide
- Preferred Iupac Name
- Mineral Acid
- Hydrogen
- Chemical Formula
- Phosphorus Pentoxide
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