Intrinsic basicity constant of 10-phenyl-10-(hydroxyimino)decanoate in aqueous solutions of hexadecyltrimethylammonium bromide. Effect of salts and detergent concentration

1987 ◽  
Vol 91 (8) ◽  
pp. 2100-2102
Author(s):  
Dino. Zanette ◽  
Marcelo R. Leite ◽  
Wayne. Reed ◽  
Faruk. Nome
Keyword(s):  
Aqueous Solutions ◽  
Basicity Constant ◽  
Hexadecyltrimethylammonium Bromide ◽  
Detergent Concentration

scholarly journals An Ultrasonic Study of Sphere to Rod Transitions in Aqueous Solutions of Hexadecyltrimethylammonium Bromide.

1982 ◽  
Vol 36a ◽  
pp. 698-700 ◽  
Author(s):  
Sune Backlund ◽  
Harald Høiland ◽  
Ove J. Kvammen ◽  
Eva Ljosland ◽  
V. B. Sokolov ◽  
...  
Keyword(s):  
Aqueous Solutions ◽  
Hexadecyltrimethylammonium Bromide ◽  
Ultrasonic Study

Metal Ion Chelates of Lipophilic Alkyl Diazinyl Ketoximes as Hydrolytic Catalysts

1999 ◽  
Vol 64 (7) ◽  
pp. 1159-1179 ◽  
Author(s):  
Radek Cibulka ◽  
František Hampl ◽  
Tomáš Martinů ◽  
Jiří Mazáč ◽  
Sonja Totevová ◽  
...  
Keyword(s):  
Aqueous Solutions ◽  
Metal Ion ◽  
Hydrolytic Activity ◽  
Hexadecyltrimethylammonium Bromide ◽  
Diphenyl Phosphate ◽  
Hydrolysis Of ◽  
Metal Ligand

A series of lipophilic dodecyl hetaryl ketoximes (hetaryl = pyridin-2-yl, pyridazin-3-yl, pyrimidin-2-yl, pyrimidin-4-yl, pyrazin-2-yl as well as their methyl hetaryl homologues was synthesized and hydrolytic activity of their chelates with Co2+, Ni2+, Cu2+ and Zn2+ in a micellar matrix of hexadecyltrimethylammonium bromide or in homogeneous aqueous solutions was investigated using 4-nitrophenyl acetate, 4-nitrophenyl hexanoate and 4-nitrophenyl diphenyl phosphate as model substrates. While Co2+ and Cu2+ chelates are almost inactive, those of Ni2+ and Zn2+ exhibit considerable activity. None of the studied chelates promotes hydrolysis of the used phosphate. The effective species are chelates of the metal : ligand stoichiometry 1 : 3 and 1 : 1 with Ni2+ and Zn2+, respectively, when the ester cleavage proceeds in the micellar matrix. The 1 : 2 stoichiometry was found in aqueous solutions of Ni2+ and Zn2+ chelates of methyl ketoximes.

Surface Charge and Adsorption Characteristics for Fluoride of Hexadecyltrimethylammonium Modified Vermiculite

2013 ◽  
Vol 781-784 ◽  
pp. 2265-2268 ◽  
Author(s):  
Shi Yong Wei ◽  
Xu Hong Deng
Keyword(s):  
Aqueous Solutions ◽  
Surface Charge ◽  
Adsorption Capacity ◽  
Langmuir Model ◽  
Point Of Zero Charge ◽  
Hexadecyltrimethylammonium Bromide ◽  
Fluoride Ions ◽  
Langmuir Adsorption ◽  
Adsorption Characteristics ◽  
Adsorption Data

HDTMA-modified vermiculite (HDTMA-Ver) was formed in a suspension by the interactions between vermiculite and hexadecyltrimethylammonium bromide (HDTMA). For vermiculite and HDTMA-Ver, the pH of the point of zero charge (pHpzc) is 3.16 and 5.09, the surface charge at pH 4.5 is-0.167 and 0.083 mmol/g, and the Langmuir adsorption capacity (qmax) is 4.98 and 8.67 mg/g, respectively. The adsorption data for fluoride by vermiculite and HDTMA-Ver could be fitted by Langmuir model. The as-prepared HDTMA-Ver exhibited excellent ability to remove fluoride ions from aqueous solutions.

Quaternary Heteroarenium Aldoximes as Catalysts for Cleavage of Phosphate Esters

1995 ◽  
Vol 60 (5) ◽  
pp. 883-893 ◽  
Author(s):  
František Hampl ◽  
Jiří Mazáč ◽  
František Liška ◽  
Jiří Šrogl ◽  
Lubomír Kábrt ◽  
...  
Keyword(s):  
Aqueous Solutions ◽  
Critical Micellar Concentration ◽  
Considerable Effect ◽  
Phosphate Esters ◽  
Hexadecyltrimethylammonium Bromide ◽  
Hydrolytic Cleavage ◽  
Pseudo First Order Reaction ◽  
First Order ◽  
Diphenyl Phosphate ◽  
Hydrolysis Of

1-Methyl- (Ia - Id) and 1-dodecyl-2-, 3- and 4-hydroxyiminomethylpyridinium salts (Ie - Ih), as well as 1-methyl- (IIa) and 1-dodecyl-3-hydroxyiminomethylpyridazinium salts (IIb, IIc), were synthesized as catalysts for hydrolytic cleavage of organophosphates. The activities of the prepared catalysts were evaluated by measuring rate constants of hydrolysis of 4-nitrophenyl diphenyl phosphate (PNPDPP) under conditions of a pseudo-first-order reaction. The observed reactivity of pyridinium aldoximes Ia - Ih towards PNPDPP in neutral or slightly basic aqueous solutions (pH 7.2 and 7.8) depends on the acidity of the hydroxyimino group. The cleavage of PNPDPP is strongly accelerated in solutions of 1-dodecylhydroxyiminomethylpyridinium salts Ie - Ih above their critical micellar concentration (CMC). Considerable effect on the velocity of PNPDPP cleavage was observed when quaternary pyridinium aldoximes Ie - Ih were comicellized with inert cationic tenside hexadecyltrimethylammonium bromide (CTAB). 1-Dodecyl-3-hydroxyiminomethylpyridazinium salts IIb and IIc were unstable in aqueous solutions under the above-mentioned conditions.

Removal of chromium(VI) from aqueous solutions using zeolites modified with HDTMA and ODTMA surfactants

Clay Minerals ◽  
2015 ◽  
Vol 50 (1) ◽  
pp. 103-115 ◽  
Author(s):  
Barbara Szala ◽  
Tomasz Bajda ◽  
Anna Jeleń
Keyword(s):  
Aqueous Solutions ◽  
Sorption Capacity ◽  
Exchange Capacity ◽  
Hexadecyltrimethylammonium Bromide ◽  
Column Studies ◽  
Maximum Sorption Capacity ◽  
Chromium Vi ◽  
Modified Clinoptilolite ◽  
The Impact ◽  
Influence Of Ph

AbstractThe removal of Cr(VI) from aqueous solutions under various conditions was investigated using a natural clinoptilolite and a synthetic zeolite derived from fly-ash (Na-P1), modified either with hexadecyltrimethylammonium bromide (HDTMA) or octadecyltrimethylammonium bromide (ODTMA). The study was focused mainly on the impact of the properties of the zeolite on the sorption capacity, the sorption mechanism, the influence of pH and the durability of the immobilization. The zeolites were modified with HDTMA and ODTMA surfactants up to 100% and 120% of their external cation exchange capacity. Batch and column studies were conducted to evaluate the influence of pH and the initial Cr(VI) concentration on their efficiencies for removing chromates. The organo-zeolites show a significant ability to remove Cr(VI) from aqueous solutions. The amount of Cr(VI) removed by organo-clinoptilolite and organo-zeolite Na-P1 is greater at low pH values, whereas the sorption efficiency decreased with increasing pH. Sorption of Cr(VI) was more efficient with the HDTMA-modified organo-clinoptilolite (150 mmol Cr(VI)/kg) than the ODTMA-modified clinoptilolite (132 mmol Cr(VI)/kg). The maximum sorption capacity was obtained with the 1.2 × ECEC ODTMA-modified clinoptilolite (237 mmol Cr(VI)/kg). The organozeolites Na-P1 adsorbed Cr(VI) from aqueous solutions more effectively and were much more durable than the organo-clinoptilolites.

Small-angle neutron scattering from hexadecyltrimethylammonium bromide micelles in aqueous solutions

1986 ◽  
Vol 90 (22) ◽  
pp. 5766-5770 ◽  
Author(s):  
Stuart S. Berr ◽  
E. Caponetti ◽  
James S. Johnson ◽  
Richard R. M. Jones ◽  
Linda J. Magid
Keyword(s):  
Aqueous Solutions ◽  
Neutron Scattering ◽  
Small Angle ◽  
Small Angle Neutron Scattering ◽  
Hexadecyltrimethylammonium Bromide
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