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Activated lignin and aminosilane-grafted silica as precursors in hybrid material production

Klapiszewski L., Szalaty T. J., Zdarta J., Jesionowski T.

Physicochemical Problems of Mineral Processing

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2016

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Vol. 52, iss. 1

459--478

EN

Functional inorganic-organic hybrids were synthesized using as a precursor silica with the addition of an appropriate amount of lignin as components. Three types of silica were applied as the support: the commercial silicas Syloid 244 and Aerosil 200, and hydrated silica precipitated in a polar system. The silicon dioxide was initially functionalized with aminosilane to activate the surface, and then the silica-based material was combined with lignin oxidized using hydrogen peroxide. The obtained inorganic-organic hybrids underwent physicochemical and dispersive-morphological analysis, with comparison of the results depending on the composition of the test samples. In addition, particle size distributions were determined and the surface structure of the products assessed by scanning electron microscopy. The presence of functional groups was also determined by FTIR spectroscopy. The thermal analysis of the silica/lignin materials was also performed, as well as the elemental and colorimetric analyses, which indirectly confirmed the correctness of the synthesis process. Hybrid materials with the most favorable dispersive and morphological properties were obtained by adding a small amount of biopolymer. The thermogravimetric analysis of the SiO2/lignin hybrids indicated their good thermal stability. With increasing quantity of lignin per 100 parts by weight of silica matrix, progressive deterioration in the thermal stability of the materials was observed.

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Influence of calcination parameters on physicochemical and structural properties of co-precipitated magnesium silicate

Ciesielczyk F., Bartczak P., Klapiszewski L., Paukszta D., Piasecki A., Jesionowski T.

Physicochemical Problems of Mineral Processing

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2014

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Vol. 50, iss. 1

119--129

EN

Physicochemical properties of different oxide systems depend mostly on the method of their preparation and classification, so the main aim of the study was to obtain the MgO·SiO2 hybrid in an aqueous solution and its calcination under assumed conditions. Research scope included evaluation of the effect of the basic parameters of the calcination process (time and temperature) on the structural properties of the final materials. Products obtained by the proposed method were thoroughly characterized. The chemical composition, crystalline structure, morphology and nature of the dispersion as well as parameters of the porous structure were established. The results of research in a decisive manner confirmed the possibility of designing the properties of inorganic oxide systems such as MgO·SiO2, which will definitively scheduled into potential directions for their use.

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Preparation and characterisation of unmodified and poly(ethylene glycol) grafted magnesium hydroxide

Pilarska A., Nowacka M., Pilarski K., Paukszta D., Klapiszewski L., Jesionowski T.

Physicochemical Problems of Mineral Processing

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2013

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Vol. 49, iss. 2

701--712

EN

The method for the synthesis of either unmodified magnesium hydroxide or functionalised with poly(ethylene glycols) of different molecular weights and physicochemical properties of the products are presented. Magnesium hydroxide was obtained by the precipitation method under well defined conditions from ammonia solution and different magnesium salts. Dispersive properties of the products were characterised by polydispersity index, particle size, as well as SEM images. Crystalline structure of magnesium hydroxide samples were determined by the WAXS method. To confirm the presence of functional groups introduced by appropriate modifiers the samples were subjected to spectroscopic analysis. Electrokinetic stability of the studied samples was determined on the basis of zeta potential dependence vs. pH measurements. The modification has resulted in reduction of particle diameters in some Mg(OH)2 samples.