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Statistical approach to the production of cement composites doped with ZnO and ZnO-based materials

Klapiszewska Izabela, Balicki Sebastian, Wilk Kazimiera A., Klapiszewski Łukasz, Ślosarczyk Agnieszka

Physicochemical Problems of Mineral Processing

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2023

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Vol. 59, iss. 4

art. no. 168352

EN

In this study, physical and functional properties of the cement composites containing ZnO, ZnO/lignin and lignin admixtures were investigated using Response Surface Methodology (RSM). The I-optimal design based on RSM was used to assess the influence of ZnO-based doping agent, of either commercial or synthetic origin, on cement composite production in the function of average compressive strength and cost. Polynomial mathematical models were developed by RSM confronting results from the experimental design. The accuracy and precision of the utilized models established by I-optimal design were tested using Analysis of Variance (ANOVA). The first stage of formulation optimization revealed that the use of commercially available ZnO-based admixture no. 4 (ZnO-SA, supplied by Sigma Aldrich) allowed to achieve the desired results, passing all the requirements, i.e., the best microbial purity combined with reasonable cost, followed by satisfactory physical properties. In the second stage of formulation optimization, the influence of implementing the hybrid materials, i.e., ZnO-SA mixed in different proportions with lignin was evaluated. RSM revealed that doping admixture no. 3, i.e., ZnO-SA/lignin (5:1), is the best candidate, which comprised augmented functional and physical properties of the fabricated cement composite. This component exhibited the best microbial purity as well as the lowest total pore volume, followed by satisfactory physical properties. Verification of the model findings indicated considerable agreement between the predicted and experimental values. From the findings, it was confirmed that a reasonable cost-performance balance for cement composites can be achieved using ZnO-SA and ZnO-SA/lignin (5:1).

2

Zinc oxide as a functional admixture to cement composites

Klapiszewska Izabela, Ławniczak Łukasz, Parus Anna, Jesionowski Teofil, Klapiszewski Łukasz, Ślosarczyk Agnieszka

Physicochemical Problems of Mineral Processing

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2022

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Vol. 58, iss. 2

art. no. 145565

EN

There is an increasing trend in the modern construction industry to use nanomaterials, which allow to improve the performance of construction materials on the one hand, and to shape new properties on the other. This study presents the results of physicomechanical and antibacterial tests for cement composites modified with zinc nanooxide. The main aim of this study was to compare the structural and morphological properties of three selected commercial zinc nanooxides and to determine the influence of the above mentioned nanooxides on the physicomechanical properties of cement composites and the ability to inhibit the activity of gram-positive and gram-negative bacteria as well as fungi. It was shown that commercial nanooxides can significantly differ in terms of physicochemical properties, which depend on their production method. Two of them were characterized by high specific surface areas, which in turn translated into rheological properties of cement mortars. Nanooxides with higher specific surface areas tend to reduce the plasticity of the mortars. According to the literature data, all nanooxides caused a delay in cement binder setting by more than 100%. This resulted in a reduction of the early one-day flexural and compressive strength of the composite. In the later curing period, especially after 7 days of hardening, a significant acceleration of the hydration process was observed in composites with the addition of all nanooxides, which was confirmed by significant increases in mechanical parameters. Nevertheless, the tested nanooxides showed different sensitivity towards microorganisms, which was influenced by both the type of nanooxide and bacteria.

3

Influence of nanosilica and binary oxide systems on the selected physical and mechanical properties of cement composites

Ślosarczyk Agnieszka, Klapiszewska Izabela, Klapiszewski Łukasz

Physicochemical Problems of Mineral Processing

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2022

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Vol. 58, iss. 2

art. no. 144184

EN

The paper presents the results of physical and mechanical tests of cement composites that include small amounts of nanosilica, as well as systems of nanosilica with less commonly used iron and nickel nanooxides. In the work, a physicochemical analysis of the nanooxides was performed to compare their morphological and structural properties, to determine their temperature stability and to assess their behavior in the cement matrix environment. Particle distribution analysis indicated a tendency for nanooxide particles to aggregate and agglomerate, with nickel nanooxide showing the highest degree of homogeneity. For iron nanooxide, the largest size scatter and the largest particle aggregates were observed. As expected, the nanosilica displayed the highest specific surface area, whereas, both nickel and iron nanooxide exhibited higher electrokinetic and temperature stability compared to nanosilica, which guarantees their durability in high pH cement matrixes. Cement composites with oxide additions had slightly lower density and comparable absorbability after 28 days of curing, as compared to pure mortar. In the case of nanosilica, after 7 days of curing, a significant increase in compressive strength was observed in comparison with pure mortar, while the strengths were slightly lower at a later time. Synergistic application of nanosilica with nickel or iron nanooxide resulted in significant increases in strength after 28 and 90 days of curing, where the effect of nanosilica alone was not as spectacular.

4

Funkcjonalne materiały otrzymywane z udziałem ligniny : od projektowania do zastosowania

Klapiszewski Łukasz

Wiadomości Chemiczne

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2021

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[Z] 75, 11-12

1155--1169

EN

Polymers of natural origin have been gaining increasing significance in sciences, as well as the industry. Owing to their renewable nature, unique properties and wide availability, they are components that can be used for numerous advanced applications. Lignin, a biopolymer, which is a waste product separated from the widely understood biomass, most usually generated in the pulp and paper industry, falls in line with this trend. In this context, the importance of cellulose, which is used in the production of paper and by-products is greater. Whereas lignin, in the vast majority, i.e. approx. 95-98%, constitutes an energy source generated as a result of its combustion. However, nowadays, due to the huge potential arising from the specific structure of lignin and its properties, attempts are being made at using this material in many different applications within the so-called high added value. Lignin, as a commonly used polymer of unique chemical structure and properties, has recently become a source of many studies utilizing its potential in the preparation of functional materials and/or biomaterials, including hybrid ones. Such systems consist of appropriate inorganic and organic elements, which as a whole constitute a functional product with special properties, not exhibited by individual components. This provides unlimited possibilities in terms of engineering, shaping and practical application in newly developed systems. The huge interest in hybrid materials and/or biomaterials results from their potential applications, namely, in medicine, electronics, optics, electrochemistry, energy storage etc. Therefore, it nowadays becomes justified and important to try and develop new, functional systems, which owing to their specific properties could result in interesting application-wise possibilities in everyday life. Therefore, the attempt to use lignin as a source of many attractive and prospective possibilities is not without significance.

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Biokatalizatory i biopolimery w aspekcie zrównoważonej chemii

Jesionowski Teofil, Klapiszewski Łukasz, Zdarta Jakub

Wiadomości Chemiczne

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2021

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[Z] 75, 9-10

1241--1267

EN

The rapid development of industry, apart from the obvious benefits, also leads to a significant increase in the level of environmental pollution, which is related not only to the use of harmful substances in the production process, but also to the production of significant amounts of by-products and wastes, which pose a serious threat to the environment as well as to the health and the life of living organisms. There is therefore a need to limit the use of toxic substances at every stage of production, and where this is not possible, appropriate waste management and the development of effective methods of harmful substances removal. In this respect, it seems crucial to introduce the principles of Green Chemistry as widely as possible. Green Chemistry is a concept whose main assumptions focus on designing and conducting chemical processes in a way that minimizes the use and formation of harmful substances as much as possible. This staretgy is based on twelve principles that overlap with the main assumptions of environmental chemistry to improve environmental protection and reduce pollution. There are many techniques and methods that fit into the assumptions of the broadly understood Green Chemistry, the implementation of which allows for sustainable management of post-production waste and by-products as well as their effective disposal. One of such concepts assumes the use of waste substances as a valuable raw material, not only for energy, but above all as a precursor and/or component for the production of innovative materials with high utility potential. Another idea is the use of enzymes, i.e. natural biocatalysts that allow chemical transformations to be carried out under mild process conditions, without the need to use harmful solvents. What's more, enzymes can be used not only at the stage of conversion/synthesis of substrates, but they can also be efficient tools for removing harmful substances. Hence, it seems necessary to undertake attempts aimed at the widest possible management of waste substances, as well as conduct research, the effect of which is the production of functional biocatalytic systems for various applications.

6

Production of cement composites using alumina-lignin hybrid materials admixture

Klapiszewska Izabela, Ślosarczyk Agnieszka, Klapiszewski Łukasz, Jesionowski Teofil

Physicochemical Problems of Mineral Processing

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2019

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Vol. 55, iss. 6

1401--1412

EN

In the framework of this study, Al2O3-lignin hybrid materials differing in terms of the weight ratio of the inorganic and organic components were designed and obtained. The method of mechanical grinding of ingredients with simultaneous mixing using a mortar grinder and a high-performance ball mill was used in order to obtain the above-mentioned systems. The effectiveness of obtaining alumina- lignin materials was confirmed using Fourier transform infrared spectroscopy (FTIR) and, indirectly, by the colorimetric analysis. FTIR analysis allowed to confirm that hydrogen bonds formed between the components and classify the resulting systems as Ist class hybrid materials. In the course of the conducted research, the relatively high thermal stability of the hybrid materials was also confirmed and the dispersion and morphological character (SEM) of the obtained systems was determined. Favourable physicochemical and microstructural evaluation allowed to qualify the alumina-lignin hybrid systems as functional admixtures for cement mortars. As part of the tests, it was confirmed that the presence of lignin in the cement composites contributes to the increase of the plasticity of the mixture. In turn, the inorganic component allowed to preserve (and, in case of selected systems, improve) the mechanical properties of the final composites. The most favourable results of application tests were obtained for alumina-lignin hybrid systems with a weight ratios equal to 5:1 and 2:1. The analysis of these systems indicated that there is a clear improvement of mechanical properties, whit a simultaneous enhancement of the plasticity of the mixture in comparison to the reference sample.