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EN
The paper presents methods of determination of analytes of the cation group (alkyl benzyl dimethyl ammonium (BDDA-C12-C16), alkyl trimethyl ammonium (TMA), hexadecyl piridinium (HP)) in surface water and bottom sediment samples. In the sample preparation phase the solid phase extraction (SPE) or accelerated solvent extraction/ultrasound assisted extraction (ASE/UAE)-SPE technique was used and in the identification phase and quantitative determination of analytes phase - ion chromatography technique (combined with a conductivity detector (CD)). The determined concentrations were in the range below the determined method detection limit (MDL) or method quantification limit (MQL) figures up to 0.142 ±0.023 mg/dm3 or 2014 ±10 μg/kg (liquid and solid samples, respectively). Comparing concentrations of individual analytes found in liquid and solid environmental samples we may notice that surfactants containing a shorter alkyl chain in their molecules were found in higher concentrations in liquid samples (hydrophobicity increasing with the chain length).
EN
Surfactants are a group of compounds with specific physico-chemical properties and therefore they are used in many spheres of human activity. Surface-active substances undergo various physico-chemical transformations, what enables their migration between different elements of the environment and may lead to its pollution. Selected anionic surfactants were determined in samples of water from the Klodnica river (25 samples) and bottom sediments (25 samples). In most samples the presence of anionic analytes was confirmed. The determined concentration levels were in the range of up to 0.2105±0.0023 mg/dm3 or 0.207±0.010 μg/kg (surface water and bottom sediment samples, respectively). Comparing the concentrations of certain analytes found in liquid and solid environmental samples, it can be noticed that the surfactants containing a shorter alkyl chain in a molecule were present in higher concentrations in liquid samples (hydrophobicity increasing with the increasing length of the chain) and the other way round.
PL
Przedstawiono podstawowe informacje dotyczące substancji powierzchniowo aktywnych w ciekłych metalach i ich możliwego wpływu na przebieg wysokotemperaturowych procesów metalurgicznych oraz omówiono pojęcia nadmiaru powierzchniowego i aktywności powierzchniowej wykorzystywane do charakterystyki układów typu ciekły metal-pierwiastek powierzchniowo aktywny. Dokonano również analizy wpływu wybranych substancji powierzchniowo aktywnych (tlenu, siarki, selenu, telluru, ołowiu, antymonu) na właściwości powierzchniowe ciekłej miedzi
EN
In the paper, the basic knowledge regarding surface-active substances in liquid metals has been presented. The changes in surface tensions of liquid metals (caused by these substances) and their possible effect on the course of high-temperature metallurgical processes have also been described. Surface tension affects the size of interfacial area, and the area is one of the factors determining the rate of running processes. Surface-active substances showing the tendency to accumulate at the liquid metal-gas interface can also increase the rates of metallurgical processes by generating local eddies, which is connected with the areas of different surface tension values creating on the surface. They can also cause the interface blocking which decreases the rate of the processes currently running on the interface or even stop them. Besides, the concepts of surface excess and surface activity used for the description of liquid metal-surface active element systems have been presented. Also, the influence of certain surface-active substances (oxygen, sulphur, selenium, tellurium, lead and antimony) on surface properties of liquid copper has been analysed. It has been stated that the strongest influence is shown in Cu-S and Cu-O systems where even a very small amount of sulphur and oxygen, respectively, cause a significant decrease in the values of liquid copper surface tension. Selenium, tellurium lead and antimony have a weaker influence, nevertheless they also show the properties of surface-active substances.
PL
W artykule opisano metody syntezy oraz zastosowanie naturalnych związków powierzchniowo czynnych. Monoacyloglicerole są emulgatorami szeroko stosowanymi w przemyśle spożywczym. Produkowane są one na skalę przemysłową metodą glicerolizy chemicznej tłuszczów i olejów w wysokiej temperaturze z wykorzystaniem zasadowych katalizatorów nieorganicznych. W ostatniej dekadzie podejmowano wiele prób enzymatycznej syntezy monoacylogliceroli. Należą do nich hydroliza, estryfikacja kwasów tłuszczowych lub transestryfikacja oraz gliceroliza tłuszczów i olejów. Istnieją możliwości otrzymania mieszaniny mono- i diacylogliceroli drogą mikrobiologicznej degradacji tłuszczów odpadowych. Enzymatycznie otrzymane estry cukrowe kwasów tłuszczowych są szeroko stosowane jako detergenty przemysłowe w różnorodnych produktach żywnościowych.
EN
The article reviews shortly methods of synthesis and application of different kinds of natural surface-active substances. Monoacyloglycerols (monoglycerides) are the most widely used emulsifieres in the food industry. Monoacyloglycerols are manufactured on an industrial scale by chemical glycerolysis of fats and oils at high temperature employing inorganic alkaline catalyst. In the last decade, many approaches have been investigated in the enzymatic synthesis of monoacylglycerols. These are selective hydrolysis, estrification of fatty acids or transestrification, and glycerolysis of fats and oils. There are some possibilities to obtain mixture of mono- and diacyloglicerols by microbial degradation of waste fats. Sugar fatty acid esters are widely used as industrial detergents and as emulsifiers in a variety of food formulations.
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