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Biphasic calcium phosphate bioceramics doped with nanometals

Malina Dagmara, Wróbel Katarzyna, Poręba Klaudia, Wzorek Zbigniew

Engineering of Biomaterials

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2021

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Vol. 24, no. 163

98

2

The impact of reagents concentration on the efficiency of obtaining high-purity magnesium hydroxide

Radomski Piotr, Jarosiński Andrzej, Wzorek Zbigniew, Nowak Anna K.

Polish Journal of Chemical Technology

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2020

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Vol. 22, nr 2

73--77

EN

The work presents the impact of reagents concentration and the drying process on the efficiency of obtaining magnesium hydroxide and its specific surface area. Magnesium sulphate(VI) within the concentration range of 0.7–2.0 mol/dm3 was used in the research as magnesium feedstock and sodium hydroxide was used as a precipitating agent within the same concentration range. The process of obtaining magnesium hydroxide was carried out with a 25% excess of the precipitating agent in relation to the reaction stoichiometry. The obtained suspension was separated by way of multi-stage sedimentation with the use of acetone and freezing samples. Depending on the concentration of reagents the efficiency of obtaining magnesium hydroxide fell within the range of 88–99%, whereas the specific surface area – within 115–609 m2 /g, while the high purity of samples above 99% of magnesium hydroxide was maintained.

3

Life Cycle Assessment (LCA) of the integrated technology for the phosphorus recovery from sewage sludge ash (SSA) and fertilizers production

Smol Marzena, Kulczycka Joanna, Lelek Łukasz, Gorazda Katarzyna, Wzorek Zbigniew

Archives of Environmental Protection

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2020

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Vol. 46, no. 2

42--52

EN

The paper presents an application of Life Cycle Assessment (LCA) method for the environmental evaluation of the technologies for the fertilizers production. LCA has been used because it enables the most comprehensive identification, documentation and quantification of the potential impacts on the environment and the evaluation and comparison of all significant environmental aspects. The main objective of the study was to assess and compare two technologies for the production of phosphorus (P) fertilizers coming from primary and secondary sources. In order to calculate the potential environmental impact the IMPACT 2002+ method was used. The first part of the LCA included an inventory of all the materials used and emissions released by the system under investigation. In the following step, the inventory data were analyzed and aggregated in order to calculate one index representing the total environmental burden. In the scenario 1, fertilizers were produced with use of an integrated technology for the phosphorus recovery from sewage sludge ash (SSA) and P fertilizer production. Samples of SSA collected from two Polish mono-incineration plants were evaluated (Scenario 1a and Scenario 1b). In the scenario 2, P-based fertilizer (reference fertilizer – triple superphosphate) was produced from primary sources – phosphate rock. The results of the LCA showed that both processes contribute to a potential environmental impact. The overall results showed that the production process of P-based fertilizer affects the environment primarily through the use of the P raw materials. The specific results showed that the highest impact on the environment was obtained for the Scenario 2 (1.94899 Pt). Scenario 1a and 1b showed the environmental benefits associated with the avoiding of SSA storage and its emissions, reaching -1.3475 Pt and -3.82062 Pt, respectively. Comparing results of LCA of P-based fertilizer production from different waste streams, it was indicated that the better environmental performance was achieved in the scenario 1b, in which SSA had the higher content of P (52.5%) in the precipitate. In this case the lower amount of the energy and materials, including phosphoric acid, was needed for the production of fertilizer, calculated as 1 Mg P2O5. The results of the LCA may play a strategic role for the decision-makers in the aspect of searching and selection of the production and recovery technologies. By the environmental evaluation of different alternatives of P-based fertilizers it is possible to recognize and implement the most sustainable solutions.

4

Ecotoxicological aspects of the use of parabens in the production of cosmetics

Barabasz Wiesław, Pikulicka Anna, Wzorek Zbigniew, Nowak Anna K.

Technical Transactions

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2019

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Vol. 116, iss. 12

99--124

EN

Parabens are synthetic preservatives that are used on a large scale in the cosmetics, pharmaceutical and food industries. Their task is primarily to prolong the shelf life of selected products – cosmetics, medicines or food – by maintaining their microbiological purity. Parabens protect products against deterioration and microorganisms, extending their durability by up to several months without interfering with their composition and operation. Parabens do not change the aroma, taste, density or other characteristics of cosmetic or food products. However parabens, which occur in most cosmetics with a creamy or liquid formula (face creams, body lotions, foundation, tonics, lipsticks, deodorants, perfumes), are becoming increasingly worse because of the prolonged list of side effects that they may cause. The presence of intact paraben esters in human body tissues has now been confirmed by independent measurements in human urine, and the ability of parabens to penetrate human skin intact without breakdown by esterases and to be absorbed systemically has been demonstrated through not only in vitro studies but also in vivo investigation using healthy human subjects.

PL

Parabeny są syntetycznymi konserwantami, które wykorzystuje się na szeroką skalę w przemyśle kosmetycznym, farmaceutycznym i spożywczym. Ich zadaniem jest przede wszystkim przedłużanie trwałości wybranych produktów – kosmetyków, leków czy artykułów spożywczych – poprzez utrzymywanie ich czystości mikrobiologicznej. Parabeny chronią produkty przed zepsuciem i drobnoustrojami, przedłużając ich trwałość nawet o kilkanaście miesięcy i nie ingerując przy tym w ich skład oraz działanie. Parabeny nie zmieniają zapachu, smaku, gęstości oraz innych cech produktów kosmetycznych lub spożywczych. Parabeny, które występują w większości kosmetyków o kremowej lub płynnej formule (kremy do twarzy, balsamy do ciała, podkłady, toniki, pomadki, dezodoranty, perfumy) cieszą się jednak coraz gorszą sławą ze względu na wydłużającą się listę skutków ubocznych, które mogą powodować. Obecność estrów parabenów w tkankach ludzkiego ciała została potwierdzona przez niezależne pomiary w ludzkim moczu, a zdolność parabenów do penetracji nienaruszonej ludzkiej skóry bez rozpadu przez esterazy i do wchłaniania ogólnoustrojowego wykazano w badaniach nie tylko in vitro, ale także in vivo u zdrowych ludzi.