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  • Author: Łukasz Wiśniewski x
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Łukasz Wiśniewski, Monika Antošová and Milan Polakovič

Abstract

A mixture of galacto-oligosaccharides and non-prebiotic sugars was separated using a simulated moving bed unit equipped with eight packed-bed columns of a cation exchanger. In order to determine operating conditions using triangle theory, equilibrium adsorption isotherms of galactose, glucose, lactose, tri- and tetragalacto-oligosaccharide were measured. It was found that each column of the SMB unit had a maximum separation efficiency of more than 3000 theoretical plates. The achieved purity of galacto-oligosaccharides in the raffinate stream was 99.9 %, similarly 99.9 % of extract was formed by non-prebiotic sugars lactose, glucose and galactose. The productivities in the raffinate and extract, were 0.6 g/(L h) and 2.4 g/(L h), respectively.

Open access

Łukasz Nowak, Magdalena Regel-Rosocka, Barbara Marszałkowska and Maciej Wiśniewski

Removal of Zn(II) from chloride acidic solutions with hydrophobic quaternary salts

The equilibrium of zinc(II) extraction from hydrochloric acid solutions with phosphonium and ammonium quaternary salts and their application as carriers in polymer inclusion membranes were studied. The most efficient was the extraction of zinc with the use of chlorides and bromide of ammonium and phosphonium salt (more than 90%). Quaternary ammonium and phosphonium chlorides and bromide are efficient extractants of zinc(II) from hydrochloric acid solutions. Two-fold molar excess of extractant over Zn(II) is necessary for efficient extraction (100%). Solvent extraction power of the extractants studied decreases with increasing hydrophobicity of the anion in the following sequence: QPCl > QPBr > QPBis > QACl > QABF4 > QPBF4 > QPPF6 > QPNtf2. A solution of 1 M H2 SO4 is chosen as the best stripping phase from the technological and economical point of view. Transport across polymeric inclusion membrane enables concentration of the stripping solution; however it takes a very long time.

Open access

Barbara Marszałkowska, Magdalena Regel-Rosocka, Łukasz Nowak and Maciej Wiśniewski

Quaternary phosphonium salts as effective extractants of zinc(II) and iron(III) ions from acidic pickling solutions

Extraction of zinc(II) and iron(III) from hydrochloric acid solutions using quaternary phosphonium salts, Cyphos® IL 101, Cyphos® IL 104, Cyphos® IL109 and Cyphos® IL 111 in mixtures with toluene, was studied. Trihexyl(tetradecyl)phosphonium chloride (Cyphos® IL 101) and trihexyl(tetradecyl)phosphonium bis(2,4,4-trimethylpentyl)phosphinate (Cyphos® IL 104) showed the best zinc(II) and iron(III) extraction abilities. After three stages of zinc(II) extraction with Cyphos® IL 101 and Cyphos® IL 104 the efficiencies were 100 and 93.6%, respectively. Total iron(III) transport to the organic phase was achieved after two separation stages and amounted to 82.1 and 100% for Cyphos® IL 101 and Cyphos® IL 104, respectively. Zinc(II) and iron(III) could be effectively stripped from the loaded organic phases with 0.5 mol dm-3 sulfuric acid. The more hydrophobic the character of the anion type of phosphonium salts, the lower the efficiency of extraction.

Open access

Aleksandra Jezierska-Thöle, Marta Gwiaździńska-Goraj and Łukasz Wiśniewski

Abstract

Organic farming is part of a sustainable development model; at the same time it is becoming a prerequisite for the multifunctional development of rural areas. The main aim of this study is to identify the state and analyse changes in the development of organic agriculture in Poland as well as to present the possibilities for its development. The time horizon of the study covers the years 2003 to 2015. The basis of the research was an analysis of the literature, the Report of the Chief Inspectorate of Trade Quality of Agriculture and Food (IJHARS), and national empirical research; it also includes an analysis of the results of surveys carried out on organic farms in the summer of 2016, as well as our own observations. The study showed that in the years 2003-2015 Poland saw a rapid increase in the number and area of organic farms due in part to the introduction of EU subsidies. Spatial analysis of the proportions of farms by voivodeship shows that in 2015 most were recorded in Warmia-Mazuria, Podlasie and West Pomerania. Similar to the increase in the number of organic farms, the years 2003-2015 saw an increased area of organic farmland. Poland is second in the world in terms of growth in the area of organic farms. In the years 2003-2014 the average size of an organic farm remained at about 25 ha and was higher than the average size of conventional farms (10 ha). In 2014 the crop structure was dominated by fodder plants (35.8%), and meadows and pastures (31.5%). In terms of livestock production, cattle and horses had the biggest share.