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1

Flotation separation of fine scheelite and calcite by microbubbles using gum arabic as depressant

Luo Xianping, Xu Hao, Guo Wei, Zhou Jinrui, Li ZongKang

Physicochemical Problems of Mineral Processing

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2025

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Vol. 61, iss. 4

art. no. 204867

EN

This study examined the role of gum arabic (GA) as a depressant in the flotation separation of fine-grained scheelite and calcite using flotation and adsorption tests, Zeta potential and contact angle measurements, and X-ray photoelectron spectroscopy (XPS). Microbubbles were introduced to improve the flotation separation of scheelite and calcite, addressing the poor flotation performance of finegrained minerals. In the pH 9 slurry, GA significantly depress calcite while having minimal effect on scheelite. A concentrate with a WO3 grade of 60.47% and a recovery of 74.29% was achieved using GA and sodium oleate as the depressant and collector for a 1:1 mixed mineral. Adsorption tests indicated that scheelite adsorbed less GA on its surface compared to calcite. Contact angle measurements demonstrated that GA altered calcite's wettability, rendering it hydrophilic. XPS analysis indicated that GA formed a chemical interaction with the surface Ca2+ ions of calcite, whereas it exhibited weak physical adsorption on scheelite. Zeta potential measurements revealed selective chemical adsorption of GA anions on fine-grained calcite surfaces. In conclusion, the inhibition mechanism of GA on calcite is related to the chemical chelation with surface Ca2+, enabling the efficient flotation separation of finegrained scheelite and calcite, and the introduction of microbubbles can enhance the recovery of scheelite.

2

Application of organic ellagic acid as a selective inhibitor of calcite in scheelite flotation

Wu Yu, Li Xiaokang, Zhang Ying, Guan Zhenhao, He Qingrui

Physicochemical Problems of Mineral Processing

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2025

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Vol. 61, iss. 1

art. no. 199872

EN

Calcite and scheelite have the same active particles and similar crystal structure, and the flotation behavior is similar. In this paper, a kind of organic ellagic acid (EA) with low molecular weight and high stability was studied as a new environmental inhibitor of low dose calcite. The microflotation test results show that when the dosage of EA is 8 mg/L and NaOL is 30 mg/L, the recovery rate of calcite is 6.22% and the recovery rate of scheelite is 89.35%, which has obvious inhibition effect on calcite. By zeta potential evaluation and Fourier transform, the surface of calcite galena reduces its hydrophobicity and hinders the adsorption of collector. X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) analysis show that EA occurs mainly through the interaction of -OH and C=O hydrophilic groups with calcium atoms on the surface of calcite, forming Ca-O-C bonds leading to stable adsorption. New, efficient and environmentally friendly organic inhibitors are designed to selectively change the surface properties of calcite and enhance the flotation efficiency of scheelite and calcite.

3

In-situ capturing carbon dioxide capture by mechanochemical processing of K-feldspar with calcium oxide

Achimovičová Marcela, Tóthová Erika, Baláž Matej, Zubrik Anton, Briančin Jaroslav, Baláž Peter, Erdemoğlu Murat, Birinci Mustafa, Erdemoğlu Sema, Sis Hikmet

Journal of Ecological Engineering

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2025

|

Vol. 26, nr 5

401--409

EN

Capturing carbon dioxide (CO2) emissions is necessary for a multi-faceted approach to combating climate change. It is only one of several essential strategies, including reducing emissions at the source, enhancing natural carbon sinks such as minerals and rocks, and transitioning to renewable energy sources. This pioneering study used abundant and cheap K-feldspar mechanochemically modified with CaO for in situ CO2 sequestration during planetary ball milling. These innovative novel in situ CO2 capture experiments consisted of two simple steps. The first step involved the mechanochemical modification of K-feldspar using CaO and the subsequent second step, direct in situ CO2 sequestration in the same milling chamber during milling. X-ray diffraction patterns demonstrated the formation of the calcite phase, and elemental analysis confirmed the binding of approximately 1.69% carbon, representing a CO2 mineralization ratio of 6.05% after 60 min of milling with CO2 gas. Infrared spectroscopy, and thermogravimetric analysis equipped with mass spectroscopy verified CO2 mineralization of CaO-modified K-feldspar. The morphology of the product after CO2 capture containing calcite and unreacted K-feldspar was monitored by scanning electron microscopy.

4

Evaluation of a novel depressant PMAA for the separation of fluorite from calcite using NaOl as a collector

Zhang Xiaofeng, Li Qi, Qin Wenqing, Liu Cheng, Yang Siyuan

Physicochemical Problems of Mineral Processing

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2024

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Vol. 60, iss. 3

art. no. 188272

EN

It is challenging to separate fluorite from calcite due to their same calcium activated sites on their surfaces. The copolymer of maleic and acylic acid (PMAA) was used to inhibit the calcite in the flotation of fluorite. Micro-flotation results exhibited that sodium oleate (NaOl) had a good ability to collect fluorite and calcite in the scope of pH 7-10. The PMAA treatment prior to NaOl selectively depressed the floatability of calcite while allowed the flotation of fluorite, and the artificial minerals mixture plotted that fluorite/calcite could be effectively separated in the presence of PMAA/NaOl. Zeta potential results suggested that NaOl collector was absorbed on the PMAA-conditioned calcite surface but did not adsorb on the PMAA-conditioned fluorite surface. XPS results and calculational chemistry revealed the chemical interaction occurred between calcite surface and PMAA which was attributed to the calcium ions of calcite surface interacting with -COOH group of PMAA.

5

Badania wpływu minerałów hunterytu/hydromagnezytu oraz kalcytu pod kątem niepalności i właściwości mechanicznych kompozytów drzewnych

Atay Gül Yilmaz, Loboichenko Valentyna, Wilk-Jakubowski Jacek Łukasz

Cement Wapno Beton

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2024

|

R. 29, nr 1

40--53

PL

W pracy zbadano właściwości dodatków mineralnych w kompozytach drzewnych, które wpływają na palność materiału, a jednocześnie są przyjazne dla środowiska. W artykule poddano analizie wyniki pomiarów kompozytów drewnianych, będących naturalnym materiałem budowlanym wielu domów, a także elementów ich wyposażenia. Jako matrycę zastosowano trociny drzewne. W pracy zbadano wpływ współobecności kalcytu i minerału mieszanego huntyt/hydromagnezyt. Kalcyt zastosowano jako minerał pomocniczy oprócz huntytu/hydromagnezytu, w celu uzyskania lepszego środka zmniejszającego palność zgodnie z normą UL94 i właściwości mechanicznych kompozytu drzewnego, takich jak wytrzymałość na zginanie i moduł sprężystości przy zginaniu. Uzyskane wyniki oceniano w zależności od zawartości składników mineralnych w kompozytach. Wyniki wykazały, że próbka 40S/50H/10C jest optymalna pod względem stosunku modułu sprężystości do niepalności. Materiały ognioodporne można stosować w budownictwie, a także w elektrotechnice, np. w gaśnicach akustycznych [np. do budowy falowodu].

EN

This work examines the characteristics of mineral additives in wood composites that affect the fire retardant properties of the material, and at the same time are environmentally friendly. The paper analyzes the results of measurements for wood composites, which is the natural building material of many houses, as well as elements of their furnishings. Sawdust waste was applied as a matrix. In the paper, a co-presence effect of calcite and huntite/hydromagnesite mineral was investigated. The calcite mineral was used as auxiliary minerals in addition to the huntite/hydromagnesite mineral to obtain a better flame retardant according to the UL94 standard and mechanical properties in the wood composite, such as flexural strength and flexural modulus. The results obtained were measured and evaluated depending on the mineral content of the composites. The results indicated that sample 40S/50H/10C is the most optimal in terms of the ratio of the modulus of flexibility and fire retardant characteristics. Fire retardant materials can be used in the construction industry, as well as in the electrical engineering applications, such as for acoustic fire extinguishers [e.g. for waveguide construction].

6

Characterization of detrital sediments within a stalagmite : their origins and influence on stalagmite morphology

Eren Muhsin, Pavlanov Muhammetmyrat

Annales Societatis Geologorum Poloniae

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2024

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Vol. 94, No. 3

287--296

EN

This study examines the detrital sediments within a stalagmite from Küpeli Cave in southern Turkey, investigating their origin and role in shaping the morphology of the stalagmite. Its longitudinal section displays distinct macroscopic layering with alternating light and dark layers. The former layers mainly comprise mosaic and columnar sparite calcite, whereas the latter layers primarily consist of carbonate grains. The detrital sediments, consisting of carbonate grains, are divided into coarse- and fine-grained sediments. The coarse-grained detrital sediments with a size of 0.02 to 0.65 mm predominate and are characterized by poor sorting, including large, rounded, and red sand grains. The fine-grained detrital sediments consist of grains ≤ 10 μm and are characterized by good sorting. The detrital sediments most likely were derived from red soils in surface karst depressions and primarily contained grains with angular and etched boundaries caused by the chemical weathering of bedrock carbonates. The rounded large sand grains are thought to have entered the soil zone by wind or surface runoff before being incorporated into the stalagmite. Dripping water carried these carbonate grains into the cave, depositing them in depressions caused by solution processes at the top of the stalagmite during its formation. Under sediment displacement towards the periphery occurred within these depressions, owing to water splash action, forming slight elevations. This mechanism contributed significantly to the stalagmite’s distinctive appearance, resembling a partially burnt candle. The alternating calcite and detrital sediment layers reflect recurring climatic conditions, with the detrital sediments deposited during increased rainfall and the calcite layers formed during drier periods with minimal clastic input and increased evaporation. The fine-grained detrital sediments further indicate formation during drier periods with significantly reduced rainfall.

7

Krążenie płynów w skałach okruchowych : studium przypadku piaskowców krośnieńskich z rejonu Bereżek (Bieszczady Wysokie)

Solecki Marek L., Waliczek Marta M.

Przegląd Geologiczny

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2023

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Vol. 71, nr 4

227--230

EN

In this study, microscopic analysis was applied to investigate fluid flow in the Oligocene shale and sandstone samples from the Krosno Beds (Silesian Nappe, Outer Carpathians) in the Bere¿ki outcrop. Analysis of calcite generation in veins and reflectance of organic matter measurements were done. Three generations of calcite were observed, indicating three stages of fluid migration along the veins in sandstones. Moreover, oil droplets and solid bitumen migration were seen during microscopic analyses. Thermal maturity based on vitrinite reflectance measurements indicates mature organic matter to hydrocarbon generation.

8

Quinic acid as a novel depressant for efficient flotation separation of scheelite from calcite

Huang Zheyu, Kuang Jingzhong, Yu Mingming, Ding Dan

Physicochemical Problems of Mineral Processing

|

2023

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Vol. 59, iss. 2

art. no. 166008

EN

There are difficulties to the conventional depressant for achieving separation of scheelite from calcite for the sake of their similar surface properties. The paper reported that a new depressant quinic acid (QA) was used for separating scheelite from calcite. The adsorption experiments, zeta potential experiment, contact angle, FTIR, XPS analysis and crystal chemistry analysis were utilized to known the depression mechanism of selectivity. The results showed that the recovery of calcite decreased drastically after QA added, whereas hardly influenced on scheelite. The tungsten concentrate could reach 66.24% WO3 grade and 89.46% recovery with 1.5×10-4 mol•L-1 QA at pH=9. The surface adsorption quantity of the QA on calcite was much greater than scheelite, which enhanced significantly the hydrophilicity of calcite surface. Due to its negative charge, QA could be adsorbed on the surface of calcite which had positive charge instead of that of scheelite with negative charge. Subsequently, free carboxyl groups of QA could chelated with Ca2+ species on the calcite surface to form stable chemical adsorption in order to prevent the Pb-BHA to form further adsorption on that, so there was no increase significantly on hydrophobicity. However, QA was obviously weak for adsorbing while Pb-BHA which could still be chemically adsorbed on scheelite surface of pre-treated with QA.

9

Effective flotation separation of scheelite and calcite by applying methylene phosphonic acid sodium as a novel and green depressant

Zhou Hepeng, Wu Handan, Guo Jiangfeng, Tang Xuekun, Huang Wen, Luo Xianping

Physicochemical Problems of Mineral Processing

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2023

|

Vol. 59, iss. 3

art. no. 168517

EN

It is known that the flotation separation of scheelite and calcite is quite difficult due to their similar surface properites. To slove the problem, ethylenediaminetetra (methylene phosphonic acid) sodium (EDTMPS), an environmentally friendly reagent, was employed as an efficient depressant for flotation separation of calcite for the first time. In flotation experiments, it demonstrates that EDTMPS could strongly inhibit the flotation of calcite but barely affect the flotaiton behavior of scheelite, showing excellent dpress ability and selectivity. Based on a series of measurements including contact angle analysis, zeta potential, and XPS analysis, it was found that large amout of EDTMPS could be absorbed on the surface of calcite through strong chemical chelation reaction and thus inhibiting the further adsorption of NaOL. On the contrary, little EDTMPS was absorbed on that of scheelite owing to the negatively charged tungstate ions on the surface in relative terms. All in all, these results exhibit EDTMPS has excellent selective inhibition ability on calcite, which can be potentially applied in actual scheelite and calcite flotation separation process.

10

Application of diethylenetriaminepenta pentasodium salt as an eco-friendly depressant to effectively improve the flotation separation of scheelite and calcite

Zhou Hepeng, Wu Handan, Guo Jiangfeng, Tang Xuekun, Huang Wen, Luo Xianping

Physicochemical Problems of Mineral Processing

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2023

|

Vol. 59, iss. 6

art. no. 174718

EN

Diethylenetriaminepenta (methylene-phosphonic acid) pentasodium salt (DTPMPA), an eco-friendly reagent, was tried for the first time as a depressant for flotation separation of scheelite from calcite. Micro-flotation tests show that DTPMPA can selectively depress the floatability of calcite. In contrast, DTPMPA barely affects the flotation behavior of scheelite. Based on the selective depress effect, floatation separation of scheelite and calcite can be effectively achieved by using DTPMPA as depressant in artificially mixed minerals flotation tests. Based on a series of measurements, it found the surface of calcite was positively charged due to the existence of Ca ion site, which can be chelated with -PO3H- functional group on the surface of DTPMPA. In the flotation process, DTPMPA can be chemically absorbed on the surface of calcite to inhibit further collector adsorption. On contrast, little DTPMPA was adsorbed on the surface of scheelite due to the spatial site resistance and electrostatic repulsion induced by surface WO42+. All in all, these results exhibit DTPMPA has excellent selective depression ability on calcite, which can be potentially applied in the actual scheelite flotation process.

11

High Porous Ceramic for Oil/Water Separation: Calcite as a Sintering Aid

Abdulhameed Mohammed Abdulmunem, Rahman Mokdad Hayawi, Azziz Haider Nadhom

Journal of Ecological Engineering

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2023

|

Vol. 24, nr 7

88--95

EN

The effects of calcite (CaCO3) as sintering aid on the preparation of local aluminum silicate microfiltration membranes were characterized in terms of morphology, thermal shrinkage behavior, porosity, permeation performance, and pure water permeate flux for the membrane. Material selection is based on availability and formability. In order to create a suspension, an organic solvent (N-methyl-2-pyrrolidone) and a polymer binder were added to a mixture of aluminum silicate and calcium carbonate. The coagulant bath consisted of water, and the suspension was extruded into a hollow fiber using a spinneret. The membrane precursor is subjected to high temperatures up to 1250 °C and this process called the sintering process gets strong hollow fiber with high mechanical stability. The addition of the CaCO3 to the dispersion altered the structure of the resulting sintered membranes. The obtained finding demonstrates that carbon calcium addition to aluminum silicate has an affirmative on overall porosity in contrast to those made from purely natural aluminum silicate, as a result the aluminum silicate calcite ceramic microfiltration membrane, which had a high porosity of above 50%, shows the highest permeability of 35.8 ml m-2•s-1 and above 97% oil rejection when operating at 0.15 MPa trans-membrane pressure in oil-in-water separation experiments. The results show that low-cost aluminum silicate-calcite component of ceramic membranes and the manufactured ceramic microfiltration membrane can handle emulsified oily wastewater.

12

Półilościowe pomiary zawartości węglanu wapnia w historycznych zaprawach gipsowych, za pomocą fourierowskiej spektroskopii w podczerwieni

Koochakzaei Alireza, Mehrabad Mahsa Saidi, Ajorloo Bahram

Cement Wapno Beton

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2023

|

R. 28, nr 2

68--75

PL

Niniejsza praca, wykorzystuje spektroskopię fourierowską w podczerwieni, do półilościowego pomiaru zawartości węglanu wapnia, w historycznych zaprawach gipsowych. Badano 17 próbek historycznych zapraw gipsowych, związanych z Łukiem Alishāha w Tabriz w Iranie, pochodzących z okresu Ilchanidów. W badaniach, zastosowano spektroskopię fourierowską, rozproszonego odbicia w podczerwieni - DRIFTS [ang. diffuse reflectance infrared Fourier transform spectroscopy]. Przygotowano zaprawy gipsowe zawierające od 0 do 6,5% kalcytu i zbadano je za pomocą spektrometru FTIR. Krzywą kalibracji przygotowano na podstawie stosunku intensywności pasma 1485 cm-1, związanego z wibracjami wiązań grup węglanowych w kalcycie do intensywności pasma przy 660 cm-1 odpowiadającego wibracjom grupy siarczanowej w gipsie. Obliczenia zawartości węglanu wapnia w badanych historycznych zaprawach gipsowych pokazują, że jego zawartość mieściła się w zakresie 0,12% do 1,08%. Zgodnie z uzyskanymi wynikami można przyjąć, że ze względu na niewielką ilość węglanu wapnia w zaprawach, węglan dostał się do zapraw, jako zanieczyszczenie z gleby, lub w postaci rozpuszczonych soli. Może to wskazywać, że wbrew początkowym przypuszczeniom na temat niektórych z tych zapraw, mieszanka wapna i gipsu nie była używana, jako główny składnik, w ich produkcji.

EN

This paper uses Fourier transform infrared spectroscopy to semi-quantitatively measure the amount of calcium carbonate in historical gypsum mortars. 17 historical mortar samples related to Arch of Alishāh in Tabriz-Iran, belonging to the Ilkhanid period, were evaluated. The methodology used in this study was diffuse reflectance infrared Fourier transform spectroscopy [DRIFTS]. Gypsum mortars containing 0-6.5% calcite were prepared and analysed using an FTIR spectrometer. The calibration curve was prepared based on the band intensity ratio of 1485 cm-1 related to carbonate vibrations in calcite to 660 cm-1 corresponding to sulphate vibrations in gypsum. Calculating the amount of carbonate in all historical mortars shows the presence of about 0.12 to 1.08% carbonate in gypsum mortar. According to obtained results, it can be acknowledged that due to the meagre amount of carbonate in the mixture of mortars, the existing carbonate has entered the mortar as an impurity through soil or dissolved salts. This can indicate that, contrary to the initial idea about some of these mortars, lime and gypsum mixture was not used as the main component in the making these mortars.

13

Właściwości i zastosowanie kalcytu w przemyśle

Bartczak Martyna

Archiwum Wiedzy Inżynierskiej

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2023

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T. 8, Nr 1

15--17

PL

Kalcyt jest pospolitym minerałem skałotwórczym z grupy węglanów o składzie chemicznym węglanu wapnia (zwany również kalcytem lub podwójnym drzewcem i alternatywnie pisany kalcytem). Należy do ogólnej kategorii minerałów węglanów i azotanów. Swoją nazwę zawdzięcza połączeniu dwóch słów – greckiego chalix i łacińskiego calx, co oznacza wapno. Minerał ten jest jednym z najczęstszych składników kamieniotwórczych, którego kryształy tworzą m.in. wapienia, marmury i oolity. Występuje w wielu kolorach na całym świecie i stanowi ponad 4% światowej gleby. Kalcyty w czystej postaci są kolorowe i przezroczyste. Aragonit i dolomit są pod wieloma względami bardzo podobne do środowiska geologicznego kalcytu. Minerał ten znajduje zastosowanie w wielu dziedzinach naszego życia a jego wydobycie sięga już początku XX wieku (na Wyżynie Krakowsko-Częstochowskiej). Artykuł ma na celu przedstawienie wybranych zastosowań kalcytu oraz opisanie jego właściwości.

EN

Calcite is a common rock-forming mineral from the carbonate group with the chemical composition of calcium carbonate. It belongs to the general category of carbonate and nitrate minerals. It owes its name to a combination of two words - the Greek chalix and the Latin calx, which means lime. This mineral is one of the most common stone-forming ingredients, whose crystals form e.g. limestones, marbles and oolites. It comes in many colors around the world and makes up over 4% of the world's soil. Pure calcites are colored and transparent. Aragonite and dolomite are in many respects very similar to the geological environment of calcite. This mineral is used in many areas of our lives and its extraction dates back to the beginning of the 20th century (in the Kraków-Częstochowa Upland). The article aims to present selected applications of calcite and describe its properties.

14

Separation of magnesite and calcite based on flotation solution chemistry

Yao Jin, Gong Xiufeng, Sun Haoran, He Ruofan, Yin Wanzhong

Physicochemical Problems of Mineral Processing

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2022

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Vol. 58, iss. 4

art. no. 149398

EN

The dissolution characteristics of minerals, dissolution of flotation agents in solutions, and equilibrium of dissociations and associations serve as the basis for determining the optimal conditions for the effective components of flotation agents and for evaluating the interaction between flotation agents and minerals. This basis provided the theoretical support for the flotation separation of minerals. Based on this, the flotation separation of magnesite and calcite was realized using sodium dihydrogen phosphate, also known as monosodium phosphate (MSP), as a regulator and dodecylamine (DDA) as a collector. When MSP was used in the DDA system, single-mineral and binary mixed-ore flotation tests revealed that the floatability of calcite was significantly greater than that of magnesite and the separation of magnesite and calcite was more effective, respectively. Zeta potential measurements showed that MSP-containing negative groups could selectively reduce the zeta potential of calcite and promote the adsorption of DDA-containing positive groups on the surface of the calcite. However, this effect was negligible on the zeta potential of magnesite. Due to the stronger affinity of MSP to Ca2+ than that to Mg2+, as demonstrated by Fourier transform infrared and X-ray photoelectron spectroscopy analyses, the MSP was adsorbed onto the surface of calcite primarily by hydrogen bonds rather than magnesite, which promoted the stronger adsorption of DDA-containing positive groups on the surface of the calcite. As a result, the differences in the floatability of magnesite and calcite were enlarged by MSP. Thus, MSP can be utilized an effective regulator for the efficient separation of magnesite from calcite via reverse flotation.

15

Influence and mechanism of Zn2+ on fluorite/calcite in sodium hexametaphosphate flotation system

Ruitao Liu, Dan Liu, Ruofan Sun, Daqian Wang, Wenkang Zhang, Yuebing Liu, Shuming Wen

Physicochemical Problems of Mineral Processing

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2022

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Vol. 58, iss. 6

art. no. 151676

EN

Fluorite and calcite have similar surface properties and natural floatability, so their flotation separation has always been a problem faced by the beneficiation industry. The key to flotation separation is the choice of depressants. Sodium hexametaphosphate (SHMP) has a good effect on fluorite calcite selective inhibition. In this paper, the effects of Zn2+ on the selective inhibition of SHMP in the flotation process of fluorite and calcite were studied through single mineral and artificial mixed mineral flotation experiments. Solution chemical calculation, X-ray photoelectron spectroscopy (XPS), Fourier Transform Infrared spectroscopy (FT-IR) and Time of Flight Secondary Ion Mass Spectrometry (ToF-SIMS) analyses investigated the mechanism of action of Zn2+, which had the most significant negative effect on the selective inhibition of SHMP. The results show that the main components of SHMP inhibiting minerals are HPO42- and H2PO4-, which can react with Ca active sites on the mineral surface to form hydrophilic Ca(H22PO4)2 and CaHPO4, while Zn2+ The presence of HPO42- in solution resulted in the formation of stable ZnHPO4 complexes, thereby weakening the inhibitory effect of SHMP on minerals.

16

Enrichment of wollastonite with high calcite content

Şavran Ceyda, Türk Tülay, Irgasheva Ganjinakhon, Kangal Murat Olgaç

Physicochemical Problems of Mineral Processing

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2022

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Vol. 58, iss. 5

art. no. 153058

EN

Wollastonite plays a significant role as an industrial raw material in many fields; its exclusive properties mean that it is used in ceramics, paint, metallurgy and coatings. In nature, wollastonite mostly occurs with calcite. While the most common method for separating wollastonite from calcite is calcination, flotation is one of the methods for separating two minerals in a more economic, environmentally friendly way. In this study, the ore contains a large amount of calcite and augite, which is an iron bearing mineral that is subjected to magnetic separation, followed by flotation in order to obtain wollastonite and calcite concentrations individually. The SiO2, CaO and Fe2O3 contents in the ore are 28.00%, 48.20% and 0.45%, respectively. After magnetic separation has reduced the iron content, flotation experiments are carried out to find the optimum conditions. For the flotation process, the effect of particle size, pH and collector dosage are investigated. A wollastonite concentration of 84% purity is successfully achieved, with a 0.17% iron concentration under the optimal conditions of 100 micron particle size, pH 8 and 500 g/t collector dosage. The purity of the calcite is raised to 95% with the application of a cleaning stage.

17

Effect of calcite and mica contents in nepheline syenite samples on the ceramic body sintering behaviours and surface roughness

Durgut Emrah, Cinar Mustafa, Ozdemir Orhan

Physicochemical Problems of Mineral Processing

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2022

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Vol. 58, iss. 5

art. no. 149179

EN

In this study, the effects of calcite and mica contents in nepheline syenite (NS) samples beneficiated by high intensity dry magnetic separation and flotation methods on ceramic bodies were investigated in detail. The NS samples were, first, sintered to observe the physical and surface roughness properties, and characterized based on the change of NS samples such as color, shrinkage, water absorption, and surface roughness after the sintering process. L-a-b color and Ra, Rz, Rt values for the NS samples were determined. The decrease in calcite and mica contents affected the surface of sintered specimens positively by reducing roughness values. Additionally, the water absorption values were found to be directly proportional to Ra values for unglazed surfaces. In conclusion, calcite and mica minerals in NS samples negatively affected surface quality by forming pinholes due to dehydroxylation and outgassing reactions in the sintering process.

18

The effect of the main component ratios in the joint filling on the product quality

Rizaoğlu Tamer, Karataş Muhammed Ziya, Çoşkun Canberk

Mining Machines

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2022

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vol. 40, iss. 4

180--190

EN

When building materials are exposed to environmental and natural factors such as temperature differences, humidity, strong wind and earthquake in the areas where they are applied, irreversible damages such as separation, cracking and level difference occur in structures and building materials. In order to prevent these damages, the joints are left between the building materials and the gaps are filled with filling materials. The composition of the materials filling the joint gaps is also very important. The most important problems encountered in joint fillings are rupture, cracking and therefore permeability. In this study, it is aimed to compare the joint filling materials produced from different proportions of aggregate and white cement against rupture and cracking, and to determine the mixture ratio that exhibits the best performance. Five different recipes were prepared by using calcite powder as aggregate, white Portland cement as binder and water-repellent, volumizing and thickening chemical additives as auxiliary materials. On the prepared test samples; Capillary water absorption, water absorption by weight and volume, unit volume weight, saturated unit volume weight, porosity, compressive strength, bending strength, surface hardness and abrasion resistance tests were carried out. Considering the cost and environmental damage of cement, which is one of the main components in joint filler material, DD2 [Calcite (71.50%)] + White Cement (26.50%) + [Polymer + Cellulose + Plasticizer + Silicone] 2% has been detected as the most appropriate recipe.

19

Preparation and characterization of calcite for tannic acid adsorption: Optimization by response surface methodology coupled by Box-Cox transformation procedure

Tangarfa Mariam, Semlali Aouragh Hassani Naoul, Alaoui Abdallah

Physicochemical Problems of Mineral Processing

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2021

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Vol. 57, iss. 3

36--45

EN

Calcite depression is the most effective physicochemical process to valorize fluorine mineral. This process is achieved by adsorption of tannic acid, as the commonly used reagent, onto calcite. Adsorption investigation is very important in mineral processing. The present work focuses on optimization of physicochemical parameters of tannic acid adsorption onto calcite. Experimental study is carried out by a response surface methodology based on Box-Behnken design. Obtained results are exploited to develop a statistical model. Analysis of variance and residuals are performed to check the significance of tested models. Among these models, Cox-Box model predicts very well the obtained experimental data. This model shows that initial tannic acid concentration and solution pH as well as their interactions are the most significant parameters. Optimal conditions are achieved using the obtained statistical model. The present investigation is an important preliminary step to better understand calcite flotation behavior using tannic acid as a depressant.

20

Homogenization phenomena of surface components of fluorite and calcite

Sun Ruofan, Liu Dan, Zhang Benyue, Lai Hao, Wen Shuming

Physicochemical Problems of Mineral Processing

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2021

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Vol. 57, iss. 1

250--258

EN

The flotation separation of fluorite and calcite poses one of the most difficult problems in the mineral processing industry. In particular, the surface homogenization of fluorite and calcite worsens the result of fluorite flotation. In this paper, time of flight secondary ion mass spectrometry and principal component analysis are used to study the surface homogenization of fluorite and calcite during grinding and in solution using X-ray photoelectron spectroscopy, infrared spectroscopy, and solution chemical calculations. The results show that the surface composition of calcite converts to fluorite after mixed grinding and that the surface composition of fluorite also converts to calcite in clarified calcite solution.