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1

Od pyłu do granulatu...

Pabiś-Mazgaj Ewelina, Gawenda Tomasz

Kierunek Surowce

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2024

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nr 1

64--70

PL

Przeprowadzone badania wykazały, że okres sezonowania ma zmienny wpływ na właściwości mechaniczne i sorpcyjne granulatów zeolitowych z zastosowaniem różnych lepiszczy, szczególnie w przypadku wykorzystania spoiw o właściwościach hydraulicznych i pucolanowych.

2

Low Temperature Thermal Activation of Sarulla Natural Zeolite for Ammonia Removal Using Fixed Bed Column Adsorption Process

Husin Amir, Aruan Friday Hotmauli, Huda Adri

Journal of Ecological Engineering

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2024

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Vol. 25, nr 11

354--364

EN

A local natural zeolite from Sarulla in North Sumatra has been isolated and activated with low thermal activation process to enhance its ammonia adsorption capacity. The Sarulla Natural Zeolite (SNZ) was prepared through crushing, sieving, washing, and thermal activation at 120 °C for three hours. SNZ was further characterized and tested for ammonia removal using batch and fixed bed column adsorption processes. In the fixed bed column adsorption, the bed height and initial ammonia concentration were used to understand the adsorption process. The batch adsorption result demonstrates the low thermal activation process improves approximately 10% of the adsorption capacity of SNZ. The kinetics study confirmed that the ammonia adsorption mechanism is chemisorption mechanism where the initial concentration plays the role in determining the mass transfer driving force. Furthermore, the rise on bed height do not provide more contact sites and extend the breakthrough time due to lack of flow blockage. The flow blockage limits the contact between zeolite and ammonia which further perform low adsorption capacity. 2 cm of bed height with 150 mg/L of initial concentration exhibit the highest adsorption capacity of 15.3551 mg/g. The result shows that the low thermal activation approach is an effective way to improve the SNZ adsorption capacity.

3

Catalytic Gasification of Fine Coal Waste Using Natural Zeolite to Produce Syngas as Fuel

Aprianti Nabila, Faizal Muhammad, Said Muhammad, Nasir Subriyer, Fatimura Muhrinsyah, Masriatini Rully, Kurniawan Ian, Sefentry Aan

Journal of Ecological Engineering

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2023

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Vol. 24, nr 9

1--9

EN

The valorisation fine coal waste is still very limited in creating energy, especially syngas. This study aims to convert fine coal waste into synthetic gas via gasification using catalyst. Fine coal gasification takes place at 350–750 °C in an updraft gasifier using catalyst of 12.5–25 wt% natural zeolite. The research results show that the addition of zeolite has synergy with increasing temperature. The syngas produced at 750 °C and 12.5 wt% zeolite consisted of 32 vol% H2, 30.1 vol% CO, 27.7 vol% CH4 and 5.1 vol% CO2. The carbon conversion efficiency and high heating value (HHV) of synthetic gas are 88.34% and 18.97 MJ/Nm3. Fine coal has the potential to be reused as an energy source in the future.

4

A selection of compositions of high strength and low thermal conductive energy efficient concretes with local materials

Nareklishvili Tea, Dzotsenidze Medea, Sheklashvili Erekle

Budownictwo o Zoptymalizowanym Potencjale Energetycznym

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2023

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Vol. 12

33--40

EN

In the world, inert materials are used to obtain high-strength concrete, the volume weight of which is quite large. We cannot get concrete with low thermal conductivity from such inert materials. Therefore, in order to obtain high-strength, environmentally friendly and energy- -efficient concrete, it was necessary to investigate local inert materials. The subject of research is natural zeolite and recycled ceramic waste, as well as polystyrene as an additive and micro-silica in cement mass to achieve penetrating waterproofing. The mentioned materials are obtained in Georgia in sufficient quantity, which allows us to produce energy-efficient concrete of high strength, low thermal conductivity, as well as sound and waterproofing. It is safe for both people and the environment. The correct mix will be provided by materials found in the local market, and the desired and low energy efficiency ensures the production of an environmentally friendly concrete.

5

Synthetic Gas Production from Fine Coal Gasification Using Low-Cost Catalyst

Andican Akbar, Faizal Muhammad, Said Muhammad, Aprianti Nabila

Journal of Ecological Engineering

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2022

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Vol. 23, nr 5

64--72

EN

The utilisation of fine coal waste is still limited, even though its availability is very abundant in the mining industry. This study utilises fine coal by converting it into syngas through catalytic gasification. The gasification process was carried out at a temperature range of 350–550°C for 10–50 minutes using natural zeolite as a catalyst. The syngas composition and quality parameters were evaluated through the H2/CO ratio, heating value, and gasification efficiency. From the research results, fine coal contained high amounts of carbon and fixed carbon. Temperature is the variable that most influences the gasification process. The addition of zeolite actively increased the CO content in the syngas. The H2/CO ratio of syngas >1, the highest HHV and LHV 16.15 and 14.46 MJ/Nm3 with the highest carbon conversion efficiency value of 88.85%, made fine coal very suitable to be used as raw material for the gasification process to produce environmentally friendly syngas.

6

Using Jordanian Natural Zeolite for Capturing Hydrogen Sulfide Gas

Al Jarrah Asem Mohammad

Ecological Engineering & Environmental Technology

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2022

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Vol. 23, iss. 5

164--168

EN

In this work a fixed bed column was used to study the adsorption capability of Jordanian natural zeolite for capturing H2S gas. The effect of pressure, inlet concentration, and zeolite particles size was study, and the breakthrough curves were obtained. The results indicate that Jordanian natural zeolite is an effective material for capturing H2S gas at a pressure around 5 atm or more and the adsorption capacity is comparable to commercial zeolite. At a pressure of 6atm or more, the saturation adsorption capacity of zeolite is about 0.24 g H2S/g zeolite. For pressure more than 6 atm the adsorption capacity remains almost the same, and therefore, 6 atm is the suitable operating pressure for Jordanian natural zeolite to capture H2S.

7

Evaluation of Jordanian Natural Zeolite for Removing Iron Ions from Underground Water

Al Jarrah Asem Mohammad

Ecological Engineering & Environmental Technology

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2022

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Vol. 23, iss. 4

10--14

EN

The content of iron ions (Fe+2 and Fe+3) in Jordanian underground water highly exceeds the standard limits in certain places. Since Jordanian water resources are very limited, the removing of these ions by cheap methods is very important. Natural zeolite which is available in Jordan in large amounts is very attractive for this purpose. The objective of this research is to evaluate Jordanian natural zeolite for removing iron ions from underground water. Batch process was used for the evaluation. The concentration of iron ions versus time for different amount of zeolite concentrations and sizes was evaluated. The results indicate that, Jordanian natural zeolite is very effective for removing iron ions from water. The zeolite concentration of about 10g/L is capable of removing almost all iron ions from water in few hours.

8

Post-fire impact behavior and durability of steel fiber-reinforced concrete containing blended cement-zeolite and recycled nylon granules as partial aggregate replacement

Nematzadeh Mahdi, Nazari Ali, Tayebi Morteza

Archives of Civil and Mechanical Engineering

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2022

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Vol. 22, no. 1

art. no. e5, 2022

EN

Recycling polymeric waste in concretes to replace a portion of the stone aggregate volume can improve some of the mechanical features of concrete such as impact resistance, while also helping mitigate the associated environmental problems. Thus, this research was aimed at exploring the combined effect of nylon granules (0, 10, and 20%) as a replacement for fine aggregate, steel fibers (0, 0.75, and 1.25%), and zeolite (0, 10, 15, and 20%) as a replacement for cement on the impact resistance and durability of concrete following several heating levels (20, 300, and 600 °C). For this purpose, 432 concrete samples were manufactured, and the concrete features including compressive strength, tensile strength, impact resistance, loss of weight, water absorption, porosity, density, and failure type of concrete samples after different heating levels were investigated. The results demonstrated that the impact energy at the failure level declined considerably with temperature for all the concrete samples containing nylon granules and steel fibers (by 46–94% for 600 °C). However, increasing nylon granule content to 20% in concrete improved the impact resistance at the first and ultimate crack levels following exposure to 20 and 300 °C, while significantly lowering this parameter (by up to 40%) following exposure to 600 °C. Furthermore, the inclusion of steel fibers in concrete and increasing its content led to increased impact energy of the heated and non-heated concretes.

9

Post-fire behavior evaluation of concrete mixtures containing natural zeolite using a novel metaheuristic-based machine learning method

Ashrafian Ali, Shahmansouri Amir Ali, Bengar Habib Akbarzadeh, Behnood Ali

Archives of Civil and Mechanical Engineering

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2022

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Vol. 22, no. 2

art. no. e101, 1-25

EN

More eco-friendly and green concretes are needed to lower the climatic and environmental impacts of the growing demand for concrete. Despite the growing interest in using natural zeolite (NZ) in cement-based materials as an eco-friendly alternative for ordinary Portland cement (OPC), there is limited knowledge regarding the post-fire mechanical properties of natural zeolitic concrete (NZC). Hence, the development of a global model is desired to better explore the strength behavior of NZC after exposure to elevated temperatures. This study focused on the post-fire behavior of low-to-high-strength NZC specimens using a novel evolutionary method. Therefore, a widespread experimental program was designed to perfectly investigate the post-fire compressive strength of NZC. The experimental results were then used to develop an evolutionary-based machine learning (ML) model. To do so, the multivariate adaptive regression splines (MARS) method was hybridized with a new metaheuristic algorithm, the Horse herd Optimization Algorithm (HOA). Besides, the results of five different ML models, namely standalone MARS, M5P model tree (M5P), extreme learning machine (ELM), Gaussian process regression (GPR), and gene expression programming (GEP) were employed for comparison with the performance of metaheuristic-based MARS (Meta-MARS) model. Further external validation was conducted to show the superior performance of the Meta-MARS model. Also, a parametric study was conducted to demonstrate the robustness of the developed model. Moreover, an uncertainty analysis inspired by the Monte Carlo simulation (MCS) method was applied to the prediction results. Results of the modeling provided new insight into the post-fire behavior of NZC and agreed well with the experimental results. The satisfactory post-fire performance of NZC is promising and shows the climatic, environmental, and economic advantages of utilizing natural pozzolans.

10

Zastosowanie zeolitu naturalnego w posadzkowym betonie nawierzchniowym

Wolka P., Żebrowski W., Karczewski B.

Materiały Budowlane

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2018

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nr 9

13--16

PL

W artykule oceniono wpływ zeolitu naturalnego jako częściowego zamiennika cementu na stwardniały beton posadzkowy. Zaprezentowano wyniki porównawcze powierzchni właściwej, gęstości właściwej, wodożądności oraz czasu wiązania zeolitu i cementu. Wykonano cztery serie mieszanek betonowych wg norm NO-17-A204 oraz PN-EN 206-1, o różnej procentowej zawartości zeolitu naturalnego z przeznaczeniem na posadzkowy beton nawierzchniowy. Określono cechy fizyczne świeżego betonu oraz parametry fizyczne, mechaniczne i trwałość stwardniałego betonu, co pozwoliło na porównanie modyfikowanego betonu i jego tradycyjnego odpowiednika.

EN

The article assessed the influence of natural zeolite as a partial cement substitute on hardened concrete flooring. In the article presented results of specific surface area, density, water absorption and setting time zeolite and cement. Four series of concrete mixes were made, based on the norms NO-17-A204 and PN-EN-206-1 with a different percentage of natural zeolite for the purpose of flooring concrete. Shown physical characteristics of fresh concrete as well as physical parameters, mechanical and durability of hardened concrete, which allowed for comparison of modified concrete in relation to traditional equivalent.

11

Nowoczesne betonowe posadzki przemysłowe z dodatkiem naturalnej pucolany

Wolka P., Żebrowski W., Karczewski B.

Materiały Budowlane

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2018

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nr 10

26--29

PL

W artykule zaproponowano dodatek naturalnej pucolany do betonów przeznaczonych na posadzki przemysłowe w postaci zeolitu o zróżnicowanym uziarnieniu. Kompozycję mieszanki betonowej oraz metodę badawczą przyjęto zgodnie z normą NO-17-A204:2015, dotyczącą nawierzchni lotniskowych. Przedstawiono porównawcze zestawienie badań charakterystyk stwardniałego betonu referencyjnego z betonem modyfikowanym zeolitem mające na celu wykazanie zmian poszczególnych cech fizycznych, mechanicznych, a także trwałości.

EN

In article proposed the addition of natural pozzolana to concretes intended for industrial floors in the form of zeolite of varied grain size. The composition of the concrete mix and the research methodology was adopted based on the standard NO-17-A204:2015 for airport pavements. A comparative comparison presented the characteristics of hardened reference concrete with zeolite modified concrete to show changes in individual physical, mechanical and durability characteristics.

12

Właściwości zeolitu naturalnego i syntetycznego oraz ich wpływ na efekt spienienia asfaltu

Franus W., Woszuk A., Bandura L., Zofka A.

Materiały Budowlane

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2017

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nr 8

60--64

PL

W artykule omówiono wpływ dodatku dwóch różnych zeolitów na efekt spienienia asfaltu niemodyfikowanego 35/50. Zastosowano zeolity o dwóch typach struktury krystalicznej: zeolit syntetyczny Na-P1 i zeolit naturalny klinoptilolit. Oba materiały zeolitowe były przed procesem spienienia asfaltu dodatkowo nasączane wodą, co sumarycznie dało cztery materiały bazowe do badań. Ilość zeolitu dozowanego do asfaltu wynosiła 5% w stosunku do masy asfaltu. Efekt spienienia, którego miarą była zmiana lepkości dynamicznej, przeanalizowano w zależności od właściwości fizykochemicznych zeolitów. Stwierdzono, że efekt spienienia zależy od ilości wody w strukturze zeolitu, sposobu jej uwalniania, rodzaju kationów wymiennych, stosunku krzemu do glinu i właściwości teksturalnych.

EN

This paper presents an investigation on the influence of two different zeolite additions on the 35/50 unmodified asphalt foaming. We examined the zeolites of two different crystal framework types: synthetic zeolite Na-P1 and natural zeolite clinoptilolite. Both zeolite materials were soaked with water before the asphalt foaming process, which gives, in summary, four basic materials for the study. The amount of zeolite doused on the asphalt was 5% in relation to the asphalt mass. The foaming effect, expressed as changes in dynamic viscosity, was analysed with respect to the physicochemical properties of the zeolites. It was found that the asphalt foaming effect depends on the amount of water in the zeolite structure, the way water is released, the kind of exchangeable cations in zeolites, the Si/Al ratio and textural properties.

13

Application of Natural Zeolite for Intensification of Municipal Wastewater Treatment

Andraka D., Dzienis L., Myrzakhmetov M., Ospanov K.

Journal of Ecological Engineering

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2017

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Vol. 18, nr 2

175--181

EN

The purpose of this research was to prove that a hybrid system including activated sludge and biofilm attached to carrying media (natural zeolite) could improve the efficiency of municipal wastewater treatment. The study was performed using a pilot-scale plant installed on Almaty Wastewater Treatment Plant (Kazakhstan) and treated sewage after preliminary mechanical pretreatment. The investigations were conducted in 2 stages: with installation without packing media (activated sludge only) and packed with zeolite from Chankanaysky field (activated sludge and biofilm). Results from the study showed a significant improvement of treatment efficiency for all examined parameters (BOD, COD, suspended solids, nitrogen compounds and phosphates). Microbiological examination of biomass from the bioreactor indicated high diversity and activity of identified species, proving good conditions both of activated sludge and biofilm.

14

Adsorpcja wielopierścieniowych węglowodorów aromatycznych ze ścieków komunalnych na naturalnym zeolicie

Chaber P., Gworek B.

Przemysł Chemiczny

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2016

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T. 95, nr 3

364--368

PL

Aglomeracje miejskie są źródłem wzrastającej ilości ścieków komunalnych zawierających zanieczyszczenia. Dokonano oceny przydatności zeolitu naturalnego zawierającego w swoim składzie heulandyt i klinoptilolit jako sorbentu usuwającego wielopierścieniowe węglowodory aromatyczne (WWA) ze ścieków komunalnych. Przeprowadzone doświadczenia w układzie statycznym i dynamicznym wykazały, że zeolit naturalny jest efektywnym sorbentem WWA w środowisku ścieków komunalnych i może być używany do oczyszczania tych ścieków z WWA, zwłaszcza 5- i 6-pierścieniowych.

EN

A heulandine and clinoptilolite-contg. zeolite (granulation 0.5–1.0 mm) was used as a sorbent in the tests performed under static condition (i) (10 ng, contact time 1 or 24 h) and dynamic condition (ii) (100 g in a column with diam. 70 mm, rate of wastewater flow 20 mL/min, analyses every 5 min). The concn. of 5 and 6 ring polycyclic arom. hydrocarbons in the wastewater, purified under (i) conditions, was reduced after 1 h treatment by 58% and 35% resp., and after 24 h by 52% and 68% resp. Under (ii) conditions, the pollutant concn. after 1 h treatment decreased by 89% and 90%, resp.

15

Application of natural zeolite for intensification of municipal wastewater treatment

Ospanov O., Myrzakhmetov M., Andraka D., Dzienis L.

Journal of Ecological Engineering

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2016

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Vol. 17, nr 5

57--63

EN

The purpose of this research was to prove that a hybrid system including activated sludge and biofilm attached to carrying media (natural zeolite) can improve the efficiency of municipal wastewater treatment. The study was performed using a pilot-scale plant installed on Almaty Wastewater Treatment Plant (Kazakhstan) and treated sewage after preliminary mechanical treatment. The investigations were conducted in 2 stages: with installation without packing media (activated sludge only) and packed with zeolite from Chankanaysky field (activated sludge and biofilm). The results from the study showed a significant improvement of treatment efficiency for all examined parameters (BOD5, COD, suspended solids, nitrogen compounds and phosphates). Microbiological examination of biomass from the bioreactor indicated high diversity and activity of identified species, proving good conditions for both activated sludge and biofilm.

16

Wpływ spoiwa zawierającego klinoptilolit na odporność zapraw na korozję siarczanową

Grabowska E., Małolepszy J.

Cement Wapno Beton

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2016

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R. 21/83, nr 2

106--111

PL

W artykule badano wpływ naturalnego zeolitu – klinoptilolitu na odporność zapraw z cementu portlandzkiego na korozję siarczanową. Badania wykazały, iż obecność klinoptilolitu powoduje wzrost odporności na korozję siarczanową. Przyczyną korzystnego wpływu klinoptilolitu są właściwości pucolanowe klinoptilolitu i związane z tym zmiany w składzie fazowym zaczynu polegające na ograniczeniu ilości wodorotlenku wapnia. Zaprawy z klinoptilolitem przechowywane w roztworze siarczanu sodu wykazują utratę wytrzymałości wynoszącą odpowiednio 3% i 6% dla 25% i 40% zamiany cementu portlandzkiego przez klinoptilolit. W przypadku zaprawy odniesienia bez zeolitu spadek wyniósł 43%. Ograniczenie procesu korozji potwierdza znaczna redukcja (25% zeolitu), a nawet eliminacja (40% zeolitu) ilości ettringitu w zaprawie po ekspozycji w roztworze siarczanu. Dodatek klinoptilolitu poza wpływem na trwałość powoduje pogorszenie konsystencji zapraw ze względu na wysoką wodożądność tego zeolitu.

EN

Paper presents the results of investigations on the influence of natural zeolite-clinoptilolite on sulphate resistance of Portland cement mortars. Investigations showed, that presence of clinoptilolite increases sulphate resistance of cement mortars. The reason for profitable influence of clinoptilolite are pozzolanic properties of clinoptilolite. Due to pozzolanic proeprties there are changes in phase composition, first of all decrease in portlandite content in hardened mortars. Mortars containing clinoptilolite immersed in sodium sulphate solution exhibited strength losses of 3% and 6% for 25% and 40% replacement of cement by clinoptilolite respectively. In case of reference mortar without clinoptilolite the loss was equal to 43%. The content of ettringite formed was significantly limited (25% of zeolite) or even totally eliminated (40% of zeolite) in clinoptilolite bearing samples immersed in sulphate solution confirms mitigation of sulphate attack on mortars containing clinoptilolite. Introduction of clinoptilolite to mortars results in lower consistency due to high water demand of clinoptilolite.

17

Skin Cancer and UV Protection

Tarbuk A., Grancarić A. M., Šitum M.

Autex Research Journal

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2016

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Vol. 16, no. 1

19--28

EN

The incidence of skin cancer is increasing by epidemic proportions. Basal cell cancer remains the most common skin neoplasm, and simple excision is generally curative. On the other hand, aggressive local growth and metastasis are common features of malignant melanoma, which accounts for 75% of all deaths associated with skin cancer. The primary cause of skin cancer is long exposure to solar ultraviolet radiation (UV-R) crossed with the amount of skin pigmentation and family genetics. It is believed that in childhood and adolescence, 80% of UV-R gets absorbed while in the remaining, 20 % gets absorbed later in the lifetime. This suggests that proper and early photoprotection may reduce the risk of subsequent occurrence of skin cancer. Reducing the exposure time to sunlight, using sunscreens and protective textiles are the three ways of UV protection. Most people think that all the clothing will protect them, but it does not provide full sun screening properties. Literature sources claim that only 1/3 of the spring and summer collections tested give off proper UV protection. This is very important during the summer months, when UV index is the highest. Fabric UV protection ability highly depends on large number of factors such as type of fiber, fabric surface, construction, porosity, density, moisture content, type and concentration of dyestuff, fluorescent whitening agents, UV-B protective agents (UV absorbers), as well as nanoparticles, if applied. For all of these reasons, in the present paper, the results of UV protecting ability according to AS/NZS 4399:1996 will be discussed to show that standard clothing materials are not always adequate to prevent effect of UV-R to the human skin; and to suggest the possibilities for its improvement for this purpose enhancing light conversion and scattering. Additionally, the discrepancy in UV protection was investigated in distilled water as well as Adriatic Sea water.

18

Mechanical and durability properties of concretes incorporating natural zeolite

Markiv T., Sobol K., Franus M., Franus W.

Archives of Civil and Mechanical Engineering

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2016

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Vol. 16, no. 4

554--562

EN

This paper investigates the application of natural zeolite as a substitute of cement in concrete. It studies the mechanical and durability properties of concretes containing 10% of natural zeolite and superplasticizer, as well as 10% of natural zeolite, superplasticizer and an air-entraining agent in comparison to concretes without natural zeolite. The study shows that fresh concrete mixture containing zeolite due to its high surface area demands a higher dosage of superplasticizer to achieve the targeted slump flow. While concretes containing natural zeolite characterize a lower compressive strength until 90 days of hardening, the compressive strength exceeds the strength of the concretes without zeolite after 180 days. The results also reveal the considerable effectiveness of using a superplasticizer and an air-entraining agent in zeolite incorporating concretes on water penetration, drying shrinkage and freeze–thaw resistance of concretes.

19

Adsorption of copper ions from aqueous solutions on natural zeolite

Zendelska A., Golomeova M., Blazev K., Krstev B., Golomeov B., Krstev A.

Environment Protection Engineering

|

2015

|

Vol. 41, nr 4

17--36

EN

The adsorption of copper ions from synthetic aqueous solutions on natural zeolite (clinoptilolite) was examined. In order to determine the rate of adsorption and the copper uptake at equilibrium, a series of experiments were performed under batch conditions from single ion solutions. Equilibrium data were evaluated based on adsorption (Langmuir and Freundlich) isotherms. The adsorption kinetics is reasonably fast. In the first 20 min of the experiment, approximately 80% of Cu2+ ions is adsorbed from the solutions. Data obtained from the kinetic experiments have been described by the pseudo-second order kinetic model as well as by the Weber–Morris and Furusawa–Smith models.

20

Peculiarities of hydration processes of cements containing natural zeolite

Sobol K., Markiv T., Terlyha V., Franus W.

Budownictwo i Architektura

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2015

|

Vol. 14, nr 1

105--113

EN

In this study, properties and peculiarities of hydration processes as well as paste microstructure of blended cements containing 10% by weight of natural zeolite were investigated. Free calcium hydroxide content, crystalline hydration products and microstructural architecture of hydrated cement pastes were examined by physical and chemical methods. It was found that the addition of natural zeolite provides formation of an extra amount of fine crystalline ettringite and tobermorite-like calcium hydrosilicates of CSH (B) type in the mineral non-clinker part of Portland cement resulting in strength synthesis of cement stone with high performance properties.