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Activated biocarbons obtained from post-fermentation residue as potential adsorbents of organic pollutants from the liquid chase

Nowicki Piotr, Gruszczyńska Karolina, Urban Teresa, Wiśniewska Małgorzata

Physicochemical Problems of Mineral Processing

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2022

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Vol. 58, iss. 2

art. no. 146357

EN

A series of new synthetic carbonaceous adsorbents has been prepared via physical and chemical activation of residue of alcoholic fermentation of corn starch. Two different variants of thermal treatment procedure - microwave and conventional heating have been applied for preparing of the activated biocarbons. All the samples under investigation were characterised by elementary analysis, surface area measurements as well as determination of the number of surface functional groups. The electrokinetic properties of examined materials were studied using potentiometric titration and electrophoresis methods, which enabled determination of the surface charge density and zeta potential of activated biocarbon particles. Moreover, sorption properties of the carbonaceous materials towards two organic dyes - methylene blue and malachite green were tested. The final products were activated biocarbons of medium developed surface area ranging from 21 to 879 m2/g, showing acidic character of the surface and various content of surface functional groups. More favourable textural parameters as well as sorption properties toward both organic dyes were revealed by chemically activated samples. The obtained results indicated also considerable effect of adsorbed dye molecules on the structure of electrical double layer formed at the solid/liquid interface.

2

Effect of Co(II) ions adsorption in the hydroxyapatite/aqueous NaClO4 solution system on particles electrokinetics

Janusz W., Skwarek E.

Physicochemical Problems of Mineral Processing

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2018

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Vol. 54, iss. 1

31--39

EN

The study of the kinetics and statics of cobalt adsorption at the hydroxyapatite/electrolyte interface using radioactive isotope 60Co was conducted. The course of adsorption kinetics indicates that at the beginning adsorption proceeds quickly and then slowly. Such adsorption kinetics is best described by a multiexpotential equation. The analysis of cobalt adsorption as a function of pH and the results of H+ ions desorption/adsorption confirmed that cobalt adsorption proceeds due to ion exchange with calcium ions in the crystal lattice and hydrogen ions in the surface groups of hydroxyapatite. Cobalt ions adsorption results in the increase of the electrokinetic potential but for the solution of the initial concentration of 0.001 mol/dm3 at pH = 8.17 a reversal of the charge due to overloading of the compact layer (edl) is observed.

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Wpływ budowy segmentowej kopolimerów w lateksach akrylanowych na ich właściwości elektrokinetyczne

Makarewicz E.

Chemik

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2005

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Vol. 58, nr 4

159-165

PL

Przedstawiono wyniki badań określających właściwości lateksów akrylanowych będących kopolimerami, składającymi się z monomerów akrylanowych i winylowych, tworzących w łańcuchu segmenty miękkie oraz metakrylanowych tworzących segmenty twarde a także kwasu metakrylowego, wprowadzającego do łańcucha polimerowego jonową grupę karboksylową. Określono relację między obliczonymi parametrami kopolimeru w lateksie jak refrakcja molowa i parametr rozpuszczalności Hildebranda, a właściwościami wyznaczonymi doświadczalnie jak: wielkość cząstek lateksu, stała oddziaływania Hugginsa, przewodnictwo równoważnikowe, stopień dysocjacji grup karboksylowych itp. Stwierdzono, że istnieje korela-cja pomiędzy parametrem określającym właściwości wyznaczone doświadczalnie, takimi jak stopień dysocjacji i próg koagulacji utajonej oraz jawnej a także stałymi wyznaczonymi z równania Kohlrauscha-Onsagera. Określono wpływ pH lateksu na wartość gramorównoważnika wydzielonego polimeru na anodzie podczas elektroosadzania.

EN

Presented are findings determininig properties of copolymer latexes composed of vinil, acrylate and metacrylate monomers, and metacrylic acid. Relations between calculated parameters of the copolymer in latex, such as molar refraction and Hildebrand parameter of dissolution and the experi-mentally determined quantities such as latex particles size, Huggins constant, equivalent conductivity and degree of carboxyl groups dissociation are given. There also exists a correlation between degree of dissociation and latent or open threshold coagulation and constants of Kohlrausch - Onsager equation. Determined is the influence of latex pH value on the equivalent value of the polymer precipitated on anode.