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Organic bio-wastes as potential precursors used for preparation of activated carbons- review

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Zięzio M., Charmas B.

Annales Universitatis Mariae Curie-Skłodowska, sectio AA – Chemia

2019

vol. 74

issue 1

Currently significant amounts of wastes, which pose a real threat to the natural environment and human health, are produced worldwide. One way to get rid of waste materials is to dispose them in landfills but some of them no longer perform their function due to overfilling. For this reason, scientists pay more and more attention to the search for their possible disposal and/or recycling, as it is impossible to prevent its generation completely. Recently, many researchers have taken up the topic of the use of agri-food wastes due to their low cost and widespread availability as a starting material for the production of activated carbons. As a result, it was found out that organic wastes are very successful precursors of organic matter and the obtained activated carbons are characterized by a very well developed porous structure. The paper presents a literature review regarding the possibility of using various waste materials under different impregnation and preparation conditions to obtain activated carbons with a developed surface area and good adsorption properties.

Water structure in fungi Amanita musscaria and their composite system with hydrocompacted nanosilica A-300

61%

Krupskaya Т., Jovaišas P., Bieliauskienė R., Yelahina N., Charmas B., Turov V.

Annales Universitatis Mariae Curie-Skłodowska, sectio AA – Chemia

2017

vol. 72

issue 2

The state of water in the fruit body of the Amanita muscaria mushroom and its composite with “wetting-drying”nanosilica A-300 was studied by low-temperature 1H NMR spectroscopy. It was found that even in the initial biomaterial, part of the water is in a weakly associated state. After drying, the portion of weakly bound water decreases, but in the medium of CDCl3, almost all water becomes weakly boned. This effect is accompanied by a threefold increase (from 3.4 to 10.3 J/g) of the total binding energy of water, which, is probably due to the transition of water from the system of spherical (cylindrical) clusters to a two-dimensional film, uniformly distributed over the surface of the biomaterial. It is suggested that due to the binding by the surface of the silica from the composite, the toxic substances present in the mushroom in the form of complexes with enzymes, will not be desorbed.

A role of free silanol groups of nanosilica surface in interaction with poly(vinyl pyrrolidone)

61%

Voronina O., Malysheva M., Nosach L., Voronin E., Gun’ko V., Charmas B., Skubiszewska-Zięba J.

Annales Universitatis Mariae Curie-Skłodowska, sectio AA – Chemia

2017

vol. 72

issue 2

In this work, a role of the number of free silanol groups at a nanosilica surface (specific surface area SBET = 250 m2/g, initial amount of silanols αОН = 0.60-0.62 mmol/g) was analyzed in interaction with poly(vinyl pyrrolidone) (PVP) vs. the degree (QTMS) of silica hydrophobization by hexamethyldisilazane at 100 oC. The value of QTMS was 0.07, 0.42, 0.67, 0.81, 0.82, and 1.0. Adsorption of PVP onto a nanosilica surface was carried out from a water and water-ethanol (1:1) solutions of the polymer. It was shown that free silanol groups play a crucial role in the adsorption of poly(vinyl pyrrolidone). The value of the maximal adsorption (monolayer capacity) on completely hydrophobic nanosilica surface is approximately by 6.5 times lower than that for unmodified nanosilica

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3 Annales Universitatis Mariae Curie-Skłodowska, sectio AA – Chemia

1 2019

2 2017

3 Charmas B.

1 Bieliauskienė R.

1 Gun’ko V.

1 Jovaišas P.

1 Krupskaya Т.

1 Malysheva M.

1 Nosach L.

1 Skubiszewska-Zięba J.

1 Turov V.

1 Voronin E.

1 Voronina O.

1 Yelahina N.

1 Zięzio M.

Search results

Organic bio-wastes as potential precursors used for preparation of activated carbons- review

Water structure in fungi Amanita musscaria and their composite system with hydrocompacted nanosilica A-300

A role of free silanol groups of nanosilica surface in interaction with poly(vinyl pyrrolidone)