China
Africa
Explore chapters and articles related to this topic
Physical Properties of Individual Groundwater Chemicals
Published in John H. Montgomery, Thomas Roy Crompton, Environmental Chemicals Desk Reference, 2017
John H. Montgomery, Thomas Roy Crompton
Biological. n-Octane may biodegrade in two ways. This first is the formation of octyl hydroperoxide, which decomposes to 1-octanol followed by oxidation to octanoic acid. The other pathway involves dehydrogenation to 1-octene, which may react with water giving 1-octanol (Dugan, 1972). 1-Octanol was reported as the biodegradation product of octane by a Pseudomonas sp. (Riser-Roberts, 1992). Microorganisms can oxidize alkanes under aerobic conditions (Singer and Finnerty, 1984). The most common degradative pathway involves the oxidation of the terminal methyl group, forming the corresponding alcohol (1-octanol). The alcohol may undergo a series of dehydrogenation steps, forming an aldehyde (octanal) then a fatty acid (octanoic acid). The fatty acid may then be metabolized by β-oxidation to form the mineralization products, carbon dioxide and water (Singer and Finnerty, 1984).
Investigation of f-Element Interactions with Functionalized Diamides of Phenanthroline-Based Ligands
Published in Solvent Extraction and Ion Exchange, 2023
Emma M. Archer, Shane S. Galley, Jessica A. Jackson, Jenifer C. Shafer
Makrlik et al. investigated the Et-Ph-DAPhen and Et-EtPh-DAPhen ligands in nitrobenzene and H+ CCD− with Am3+ and Eu3+, Table 10.[86,88] The two coincidental articles contain essentially identical data showing the H+ CCD− impacts in solvent extraction. The results show that the presence of an ethyl group on the phenyl ring off the amide moiety increased the SFAm/Eu by roughly 10 to 20 units. This is unclear because the SFAm/Eu were reported as ranges unlike other studies of this type. Yang et al. examined Et-Ph-DAPhen as well using both 1-octanol and F-3 to compare the results. It was observed that the SFAm/Eu >10 for both solvents but was higher in F-3 due to the significant polarity of F-3 compared to 1-octanol.[87] The use of 1-octanol was to optimize the practical use of this ligand in less toxic or corrosive diluents that are commonly used like F-3, nitrobenzene, etc. The results showed that 1-octanol does not assist in increasing SFAm/Eu due to its low dielectric constant but maintains the SFAm/Eu equal to or greater than acceptable values (~10).
Pesticide removal from drinking water sources by adsorption: a review
Published in Environmental Technology Reviews, 2019
Stephanie Cosgrove, Bruce Jefferson, Peter Jarvis
The octanol–water coefficient (log Kow) is a measure of the hydrophobicity of a compound. This shows whether a pesticide has a preference for being in water or whether it is more likely to dissolve in the organic phase. Octanol is used due to its similar carbon to oxygen ratio to that of lipids (8:1), which are very hydrophobic. This means that octanol is non-miscible with water and so clearly separates the organic and non-organic liquid phases [57]. The polarity of a pesticide is inferred from its associated Kow value.
Selective Separation of 4,4’-Methylenedianiline, Isophoronediamine and 2,4-Toluenediamine from Enzymatic Hydrolysis Solutions of Polyurethane
Published in Solvent Extraction and Ion Exchange, 2023
Jörg Eberz, Moritz Doeker, Yannic S. Ackermann, Dominik Schaffeld, Nick Wierckx, Andreas Jupke
Separation of diamines were studied in single-stage solvent extraction and reactive extraction experiments. For solvent extraction, 1-octanol was used as solvent. For reactive extraction, OLA as reactant diluted in 1-octanol was used as organic phase. 1-octanol was chosen as diluent since it has been reported in the literature as a suitable solvent for bioprocesses and has already been successfully used in biotechnological processes in a reactive in situ extraction.[20,21] In addition, it is non-toxic, only slightly soluble in water and can be produced biotechnologically from renewable raw materials.[22] If not specified otherwise, the concentration of the reactive agent was 0.1 M. For the extraction, 1 mL of the corresponding aqueous diamine solution with a concentration of 0.5 g/L, were mixed with 1 mL solvent in 2 mL tubes. This concentration corresponds to 2.5 mM for MDA, 2.9 mM for IPDA and 4.1 mM for TDA. The water used was distilled in a MonoDest3000 (Lenz Glas Instrumente, Wertheim, Germany). An orbital Lab-Shaker LS-W (Kuehner, Birsfelden, Germany) at 150 rpm for at least 14 h realized mixing of organic and aqueous phase. After this time, it was assumed that the thermodynamic equilibrium state is reached. For phase separation, the tubes were centrifuged at 10,000 rpm for one minute with an IKA G-L centrifuge (IKA, Staufen, Germany). Before and after extraction, the amine concentration of the aqueous phase was determined via HPLC. The error of the extraction experiments is determined with the coefficient of variation based on the concentration measurement via HPLC of all samples of each experiment before extraction. This is defined as the ratio of the standard deviation to the arithmetic mean :