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Anion organic

Alkoxylated polysiloxanes are a relatively new class of dyebath lubricants. They have practically no substantivity for the substrate, yet combine adequate lubrication with water solubility and easy rinsability. If the silicones contain primary hydroxy groups, these can be modified by esterification, phosphation, phosphonation, sulphation, sulphonation or carboxylation. These anionic substituents confer substantivity for various substrates without losing rinsability. Anionic organic sulphates and sulphonates probably offer the best overall properties for dyebath lubricants, whilst other types can be more suitable for selected applications [464]. [Pg.245]

LDHs are also promising materials as sorbents for anionic organic contaminants via both ion-exchange and reconstruction reactions. There have been a large number of reports of the use of LDHs for removal of species such as aromatic carboxylic acids, phenols, pesticides, and humic or fulvic acids. Recently, Cardoso et al. [152] found that the sorption process of terephthalate anions from aqueous solutions by calcined Mg/Al - CO3 LDHs takes place by reconstruction of the LDHs and involves the intercalation and adsorption of terephthalate anions. Calcined Mg/Al - CO3 LDHs were found to be capable of removing 40 to 85 % of the benzoate from solutions in the concentration... [Pg.205]

As already stated, most anions, organic acids, cations, or aliphatic amines of interest, but not all, are characterized by poor UV absorption. [Pg.319]

Existing commercial CE instruments are able to analyze anions, organic acids, cations, and amines that do not absorb in the UV by using indirect UV or C D conductivity detection. [Pg.351]

The principal abiotic processes that may transform thorium compounds in water are complexation by anions/organic ligands and hydroxylation. The increase in the mobility of thorium through the formation of soluble complexes with CQs, humic materials, and other anions or ligands and the decrease in the mobility due to formation of Th(OH)4 or anionic thorium-hydroxide complexes were discussed in Section 5.3.1.2. In a model experiment with seawater at pH 8.2 and freshwater at pH 6 and pH 9, it was estimated that almost 100% of the thorium resides as hydroxo complexes (Boniforti 1987). [Pg.94]

Furthermore, the heterolysis reaction is catalyzed by the addition of anions (organic and inorganic oxy anions, e.g., acetate) (44,107, 110,111). Comparing the acetate effect in the presence of different chelating ligands ([15]aneN4 and nta) to those of the aquated system led to the conclusion that the oxy anions have to occupy the trans position to the R group in order to labilize the M-R bond (trans labilization effect) and thus catalyze the heterolytic decomposition (44,107,110,111). [Pg.281]

The results of model compound recovery experiments, in part, support these selection criteria. For example, the anionic resin (MP-1) yielded the best recoveries of the anionic organics (little or no adsorption was observed on subsequent resins) glycine was equally distributed (but poorly recovered) on MP-1 and MP-50 (no adsorption was observed on the nonionic resins). Although some selective adsorption occurred on the lower surface area ionic resins, the nonpolar macro-porous XAD-2 showed its retentive power for low-polarity compounds as none were seen to break through to the more polar methacrylate polymer, XAD-7. XAD-7 was included in the system for use with reclaimed and surface waters (21) because literature reports indicated that the methacrylate XAD resins had significantly better retention of humics, fulvics, and smaller phenolics (9, 29, 30). However, in the... [Pg.551]

In 1971, Starks introduced the term phase-transfer catalysis to explain the critical role of tetraalkylammonium or phosphonium salts (Q 1 X ) in the reactions between two substances located in different immiscible phases [1], For instance, the displacement reaction of 1-chlorooctane with aqueous sodium cyanide is accelerated many thousand-fold by the addition of hexadecyltributylphosphonium bromide 1 as a phase-transfer catalyst (Scheme 1.1). The key element of this tremendous reactivity enhancement is the generation of quaternary phosphonium cyanide, which renders the cyanide anion organic soluble and sufficiently nucleophilic. [Pg.1]

Gaiasafe sampler Paper strips impregnated with binding agents Metals, anions, organic compounds Screening 2 days to 2 months Solvent extraction 60... [Pg.51]


See other pages where Anion organic is mentioned: [Pg.1267]    [Pg.174]    [Pg.333]    [Pg.174]    [Pg.726]    [Pg.112]    [Pg.549]    [Pg.196]    [Pg.335]    [Pg.1486]    [Pg.353]    [Pg.58]    [Pg.298]    [Pg.18]    [Pg.299]    [Pg.22]    [Pg.277]    [Pg.7]    [Pg.1486]    [Pg.443]    [Pg.1360]    [Pg.1490]    [Pg.195]    [Pg.401]    [Pg.585]    [Pg.261]    [Pg.278]    [Pg.241]    [Pg.7]    [Pg.40]   
See also in sourсe #XX -- [ Pg.44 , Pg.388 , Pg.389 ]

See also in sourсe #XX -- [ Pg.229 , Pg.245 ]

See also in sourсe #XX -- [ Pg.44 ]




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