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Suitability and characterization of pumice, bauxite, and ferrochrome slag as alternative raw materials in vitrified ceramic industry

Benkli Yunus Emre, Koca Kazım

Physicochemical Problems of Mineral Processing

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2024

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Vol. 60, iss. 2

art. no. 187967

EN

Since the natural raw materials used in the manufacture of clay-based ceramic products vary greatly in the sintering stage, the resulting products are quite heterogeneous. In addition, different types of waste could be used to make ceramic tiles and bricks. Therefore, this study aimed to investigate the effects of pumice, bauxite, and ferrochrome slag on the vitrified ceramic body. In this context, firstly, binary slip mixtures were prepared by composing 40% clay with 60% pumice, bauxite, and ferrochrome slag one by one, which was reduced to 150 μm in particle size. Then, the mixtures were shaped by slip casting method and sintered at 1000°C, 1100°C, 1200°C, and 1250°C. The qualitative XRD analysis was performed in order to see the phase variation, and physical properties were determined with shrinkage and water adsorption measurements. Since pumice transformed into a glassy phase after sintering at 1100°C, an amorphous phase was observed in all samples produced with pumice. In addition, the mullite development occurred in clay-pumice body composition with the temperature increment. However, tridymite and cristobalite phases were analysed in clay bauxite and ferrochrome body compositions. The shrinkage and water adsorption values, which were high in the samples sintered at 1000°C, began to reduce from 1100°C to 1250°C significantly. In particular, water adsorption reached 0% in the clay-pumice system which was suitable for a fully vitrified-high density standard (ISO13006-10545/98). Besides, the brighter colour was reached in the clay-pumice system while brown and black colour was seen in clay-bauxite and clay-ferrochrome bodies, respectively.

2

Rheological properties of cement pastes modified with pumice, trass and chalcedonite powder

Spychał Edyta, Vyšvařil Martin

Structure and Environment

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2023

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Vol. 15, no. 4

217--226

EN

The article presents the influence of pumice, trass and chalcedonite powder on rheological properties of cement pastes. Cement was being replaced both of additions 10% or 20% by mass and combination of pumice or trass and chalcedonite powder in the amount 5% or 10% of each of them. The main purpose of the publication was to assess the effects of chalcedonite powder with selected mineral additions in terms of rheological properties and compare them with the results obtained for pastes modified with only one of the additions. In each case, the additive or combination of additives introduced into the paste reduced the flow, compared to the result of paste without additive(s). Rheological properties varied depending on type and amount of additive(s).

PL

W artykule przedstawiono badania wpływu pumeksu, trasu oraz mączki chalcedonitowej na właściwości reologiczne zaczynów cementowych. Cement zastępowano każdym z dodatków w ilości 10% lub 20% oraz kombinacją pumeksu lub trasu z mączką chalcedonitową w ilości po 5% i 10% każdym z nich. Głównym celem pracy była ocena współdziałania mączki chalcedonitowej z wybranymi dodatkami mineralnymi w zakresie właściwości reologicznych oraz porównanie rezultatów badań z wynikami uzyskanymi dla zaczynów modyfikowanych tylko jednym z dodatków. W każdym z przypadków dodatek lub kombinacja dodatków wprowadzone do zaczynu wpłynęły na zmniejszenie rozpływu, w porównaniu do wyników uzyskanych dla zaczynu bez dodatku(ów). Właściwości reologiczne były zróżnicowane w zależności od rodzaju i ilości dodatku(ów).

3

Effects of pumice additions on thermal and mechanical behaviors of epoxy resin

Kırbaş İbrahim

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2023

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Vol. 71, nr 4

art. no. e146286

EN

In this study, thermal conductivity, mechanical properties, and thermal degradation of pumice-added epoxy materials were investigated. 2%, 4%, 6%, 8%, and 10% of pumice was added to the epoxy resin (EP) % by weight. Various types of analyses and tests were conducted to determine the thermal conductivity, mechanical properties, and thermal degradation of these epoxy materials. The tests and analyses proved that the addition of pumice leads to a decrease in the thermal conductivity coefficient and density of the pure EP material. It also increases the degree of hardness. The addition of pumice had a positive effect on mechanical properties. Compared to pure EP, it increased the tensile strength, Young’s modulus, bending strength, and flexural modulus. As a result of TGA analysis it was determined that with the incorporation of pumice into the EP, its decomposition rate progressed more slowly. At 800_C, the carbon residue improved as a result of the addition of pumice.

4

Production of pumice-containing nanofibers by electrospinning technique

Kılıçer Ali

Materials Science Poland

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2022

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Vol. 40, No. 2

206--213

EN

The scope of the study involves identifying the optimal means to effectively use the electrospinning technique to obtain pumice-containing nanofibers. Nanofiber containing pumice in a solution was electrospun to obtain smooth, cylindrical, bead-free, and ultrafine nanomaterials. The study also analyzed the molecular [Fourier transform infrared spectroscopy (FTIR)], thermal [differential scanning calorimetry (DSC)], zeta potential, size, polydispersity index [dynamic light scattering (DLS)], and surface [scanning electron microscope (SEM)] parameters of the pumice-containing nanofibers having JP6 (applied voltage: 6 kV) and JP12 (12 kV) properties. While the distance (10 cm), flow rate (0.8 mL/h), and other parameters of the electrospinning process were fixed, two different voltages were applied to obtain the pumice-containing nanofiber. The average diameter of the nanoencapsulated pumice produced at 6 kV was defined as 98.6 nm in gelatin nanomats with 31.8 nm. The average diameter of the nanocapsule pumice produced under a 12 kV voltage was found to be 85.8 nm, and the average diameter of the nanomats (non–nanoencapsulated) was 35.2 nm. The average zeta potential values of the pumice-containing nanofiber were also determined in the nanosize range. The JP6 and JP12 PDI values were determined as 0.165 and 0.566, respectively. Peaks characteristic of pumices as defined in the literature were observed in the FTIR results, while DSC analysis results revealed strong endo- and exothermic peaks. As a result of this study, it has been proved that pumice can be reduced to nanosize with the electrospinning technique and it is nanoencapsulated in nanofiber. When the obtained pumice-containing nanofiber was examined, it was determined that the surface area of the nanofiber was large and resistant to thermal heat.

5

The Effects of Additives to Lightweight Aggregate on the Mechanical Properties of Structural Lightweight Aggregate Concrete

Khoshvatan Mehdi, Pauraminia Majid

Civil and Environmental Engineering Reports

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2021

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Vol. 31, no. 1

139--160

EN

In the paper, the effects of different percentages of additives (perlite, LECA, pumice) on the mechanical properties of structural lightweight aggregate concrete were tested and evaluated. For the research, 14 mixing designs with different amounts of aggregate, water, and cement were made. Experimental results showed that the specific gravity of lightweight structural concrete made from a mixture of LECA, pumice, and perlite aggregates could be 25-30% lighter than conventional concrete. Lightweight structural concrete with a standard specific gravity can be achieved by using a combination of light LECA with perlite lightweight aggregates (LA) and pumice with perlite in concrete. The results indicated that LECA lightweight aggregates show more effective behavior in the concrete sample. Also, the amount of cement had a direct effect on increasing the strength regardless of the composition of LAs. The amount of cement causes compressive strength to increase. Furthermore, the stability of different experimental models increased from 156 to 345 kg m3 while increasing the amount of cement from 300 to 400 kg m3 in the mixing designs of LECA and perlite for W/C ratios of 0.3, 0.35, and 0.4. For a fixed amount of cement equal to 300 kg, the compressive strength is reduced by 4% by changing the water to cement ratio from 0.5 to 0.4. The compression ratios of strength for 7 to 28 days obtained in this study for lightweight concrete were between 0.67-0.8. rate of tensile strength to compressive strength of ordinary concretes, which is approximately 10, this ratio is about 13.5 to-17.8 in selected and optimal lightweight concretes in this research, which can be considered good indirect tensile strength for structural lightweight concretes.

6

Właściwości fizyczne pumeksu i jego zachowanie jako kruszywo grube w betonie

Caiza M., Gonzalez C., Toulkeridis T., Bonifaz H.

Cement Wapno Beton

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2018

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R. 23/85, nr 6

468--478

PL

Zastosowanie lekkiego betonu zyskało popularność i powszechną akceptację w branży budowlanej na całym świecie. Jest wiele metod wytwarzania lekkiego betonu, a do jednej należy zastosowanie pumeksu jako kruszywa grubego. Głównym celem przeprowadzonych doświadczeń było określenie właściwości fizycznych pumeksu wulkanicznego, z północno-centralnego Ekwadoru i możliwości jego stosowania jako kruszywa grubego w betonie. Próbki pumeksu, konwencjonalnego kruszywa grubego i konwencjonalnego kruszywa drobnego zbadano określając skład ziarnowy, gęstość w stanie suchym, absorpcję wody, odporność na ścieranie, zawartość wilgoci i gęstość nasypową, zgodnie z normami ASTN. Skład mieszanin obliczono zgodnie z ACI 211. Do badań przygotowano po pięć próbek walcowych z kruszywem konwencjonalnym i pumeksowym. Zbadano ich wytrzymałość na ściskanie po różnych okresach, w celu porównania właściwości betonów z kruszywem klasycznym i pumeksowym.

EN

The use of lightweight concrete has gained acceptance and popularity in the construction industry worldwide. There are many methods to create lightweight concrete, one of them is the usage of pumice as a coarse aggregate. The main objective of this study has been to experimentally determine the physical properties of volcanic pumice from north-central Ecuador, when used as a coarse aggregate in concrete. Samples of pumice, conventional coarse aggregate and conventional fine aggregate were taken in order to perform the graining, dry density, water absorption, degradation, moisture content and unit mass assays according to ASTN normative. Additionally, the proportioning of the mixture has been calculated according to ACI 211, creating five test cylinders made of hydraulic concrete with conventional aggregate and five test cylinders made of hydraulic concrete using pumice aggregate, testing their compressive strength in different time periods in order to compare the results of both proportioning afterwards.

7

Response surface methodology (RSM) and its application for optimization of ammonium ions removal from aqueous solutions by pumice as a natural and low cost adsorbent

Moradi M., Fazlzadehdavil M., Pirsaheb M., Mansouri Y., Khosravi T., Sharafi K.

Archives of Environmental Protection

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2016

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Vol. 42, no. 2

33--43

EN

This research was conducted to study the adsorption of ammonium ions onto pumice as a natural and low-cost adsorbent. The physico-chemical properties of the pumice granular were characterized by X-ray diffraction (XRD), Fourier transforms infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). Modeling and optimization of a NH4+ sorption process was accomplished by varying four independent parameters (pumice dosage, initial ammonium ion concentration, mixing rate and contact time) using a central composite design (CCD) under response surface methodology (RSM). The optimum conditions for maximum removal of NH4+ (70.3%) were found to be 100 g, 20 mg/l, 300 rpm and 180 min, for pumice dosage, initial NH4+ ion concentration, mixing rate and contact time. It was found that the NH4+ adsorption on the pumice granular was dependent on adsorbent dosage and initial ammonium ion concentration. NH4+ was increased due to decrease the initial concentration of NH4 and increase the contact time, mixing rate and amount of adsorbent.

8

Immobilization of Lycinibacillus fusiformis B26 cells in different matrices for use in turquoise blue HFG decolourization

Dogan N. M., Sensoy T., Doganli G. A., Bozbeyoglu N. N., Arar D., Akdogan H. A., Canpolat M.

Archives of Environmental Protection

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2016

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Vol. 42, no. 2

92--99

EN

The decolourization of Turquoise Blue HFG by immobilized cells of Lysinibacillus fusiformis B26 was investigated. Cells of L. fusiformis B26 were immobilized by entrapment in agar and calcium alginate matrices and attached in pumice particles. The effects of operational conditions (e.g., agar concentrations, cell concentrations, temperature, and inoculum amount) on microbial decolourization by immobilized cells were investigated. The results revealed that alginate was proven to be the best as exhibiting maximum decolourization (69.62%), followed by agar (55.55%) at 40°C. Pumice particles were the poorest. Optimum conditions for agar matrix were found: concentration was 3%, cell amount was 0.5 g and temperature was 40°C (55.55%). Ca-alginate beads were loaded with 0.5, 1.0 and 2.0 g of wet cell pellets and the highest colour removal activity was observed with 2.0 g of cell pellet at 40°C for alginate beads. Also, 0.5 and 1.0 g of pumice particles that were loaded with 0.25 and 0.5 g of cell pellets respectively were used and the results were found very similar to each other.

9

Use of pumice and scoria aggregates for controlling alkali silica reaction

Tapan M.

Physicochemical Problems of Mineral Processing

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2014

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Vol. 50, iss. 2

467--475

EN

Turkey has important potential pumices reserves (68% of the reserve of the world) and 56 % of pumice reserve of Turkey is in the East Anatolia Region. It is important to assess huge pumice reserves in Eastern Turkey for its use in the cement and concrete industry. Use of acidic pumice and basic pumice (scoria) as cement additive or aggregate are gaining popularity because of their proven structural/durability properties. This paper presents the results of an investigation to assess the effectiveness of pumice and scoria aggregates in controlling alkali silica reaction (ASR) of alkali silica reactive aggregate using the following test methods: the accelerated mortar bar test (ASTM C 1260) and the scanning electron microscopy technique (SEM). The morphologies, structures and properties of the samples were determined by XRD, ICP-MS, XRF and thin section study. Mortar cubes were specially prepared according to ASTM standards using 10, 20 and 30% pumice or scoria aggregate as alkali silica reactive aggregate replacement. The results are compared with ASTM requirements to assess the suitability of pumice or scoria for preventing alkali silica reactivity. According to the results of these methods, pumice aggregates control the alkali silica reaction whereas scoria aggregates decrease expansion but is not as effective as pumice in preventing ASR. The results of SEM analysis showed alkali silica gel formation and serious decomposition of aggregate texture due to ASR in scoria added mortar bars.

10

Chemiczna aktywacja naturalnej pucolany za pomocą stałego aktywatora

Allahverdi A., Rahmani A.

Cement Wapno Beton

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2009

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R. 14/76, nr 4

205-213

PL

Otrzymano spoiwo złożone w 77% z naturalnej pucolany pumeksowej, a w 23% z aktywatora zawierającego ponad 90% cementu portlandzkiego i niewielkie ilości substancji chemicznych złożonych z siarki i metali alkalicznych. Zbadano właściwości zaczynu i zapraw sporządzonych z tego spoiwa. Czas wiązania był zawarty w granicach od 210 minut (początek wiązania) do 300 minut (koniec wiązania). Wytrzymałość zaprawy wzrastała z około 23 MPa po 28 dniach do 45 MPa po rocznym dojrzewaniu. Badania wykazały, że opracowany aktywator pozwala na otrzymanie dobrej jakości spoiwa z naturalnej pucolany pumeksowej. Jest to spoiwo niezwykle przyjazne dla środowiska.

EN

The binder was produced consisting of 77% of natural pozzolana pumice-type and 23% of activator composed chiefly of Portland cement and small addition of chemical substances containing sulfure and alkali metals. The properties of paste and mortars prepared on the basis of this binder were investigated. Setting time of the binder was the range from 210 min (beginning of setting) to 300 minutes (final setting time). The compressive strength was 23 MPa after 28 days of hardening till 45 MPa after one year of curing. The experimental results showed that the elaborated activator gives the possibility for producing good quality binder from natural puzzolana of pumice-type. This binder is very environmental friendly.