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1

Effect of flocculation behavior on the flotation of synthetic apatitedolomite mixtures based on FBRM and PVM

He Guixu, Chen Aoao, Zhao Lina, Zhang Qin, Li Wubin, Xie Jun, Wang Jieliang

Physicochemical Problems of Mineral Processing

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2025

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Vol. 61, iss. 1

art. no. 202595

EN

This study investigates the influence of various factors on shear flocculation in the apatitedolomite mixed ore flotation system. The Box-Behnken response surface methodology is employed to evaluate the interactions of these factors on flocculation behavior. Additionally, the Focused Beam Reflectance Measurement (FBRM) and Particle Vision Measurement (PVM) techniques are applied to investigate the mechanisms by which these factors affect shear flocculation. The results show that sodium oleate (NaOL) concentration, pH, and shear rate significantly influence the size of the flocculated particles. Notably, the interaction effect between NaOL concentration and pH is particularly pronounced. FBRM and PVM analysis reveals that pH and NaOL concentration play dominant roles in controlling particle flocculation, while H3PO4 has a relatively minor impact on agglomerate morphology and size. At low shear rates, the flocs are larger and more uniformly distributed, resulting in a more stable process. In contrast, although high shear rates enhance initial flocculation efficiency, they reducefloc size. Furthermore, the modified Smoluchowski model is applied to evaluate the impact of different factors on flocculation kinetics. The findings suggest that the effects of these factors vary across different stages of flocculation. The combined influence of NaOL concentration, pH, and shear rate is crucial in determining the stability of the flocs, with these three factors being key determinants of floc morphology and stability.

2

Application of fine-grained waste glass and metakaolin to limit alkaline corrosion in cement mortars

Kotsay Galyna, Młotkowska Martyna

Materiały Budowlane

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2025

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nr 5

1--9

EN

The aim of the present study was to assess the feasibility of using fine-grained waste glass combined with metakaolin in cement mortars containing reactive dolomitic aggregate. The research encompassed an analysis of the activity of the glass and metakaolin additives, as well as cement pastes incorporating these additives in amounts of 10%, 20%, and 30%, alongside investigations into alkali corrosion and the microstructure of the mortars. The results indicate that partially replacing cement with waste glass increases alkali activity and the risk of corrosion, whereas introducing a combined additive (glass + metakaolin) significantly reduces the content of active alkali, limits mortar expansion. The data obtained confirm that metakaolin exerts a stabilizing effect by counteracting the adverse consequences of the high alkalinity of glass, thereby improving the durability and chemical stability of cementitious products. stated, employing this combined additive may provide a valuable solution in the production of cement-based materials.

PL

W artykule zaprezentowano możliwości zastosowania drobno mielonego szkła odpadowego i metakaolinu w zaprawach cementowych zawierających reaktywne kruszywo dolomitowe. Badania obejmowały analizę aktywności dodatków (szkła i metakaolinu) oraz zaczynów cementowych z udziałem tych dodatków w ilości 10, 20 i 30%. Ponadto zbadano korozję alkaliczną oraz mikrostrukturę zapraw. Wyniki wskazują, że zastąpienie części cementu szkłem odpadowym powoduje zwiększenie aktywności alkalicznej i ryzyka korozji, natomiast wprowadzenie kompleksowego dodatku (szkło + metakaolin) redukuje znacznie zawartość aktywnych alkaliów i ogranicza ekspansję zapraw. Uzyskane dane potwierdzają, że metakaolin działa stabilizująco, neutralizując niekorzystne skutki dużej alkaliczności szkła, co przekłada się na zwiększenie trwałości i stabilności chemicznej wyrobów cementowych. W konsekwencji zastosowanie kompleksowego dodatku szkła i metakaolinu może stanowić wartościowe rozwiązanie w produkcji materiałów cementowych.

3

Technological research of calcinated dolomite ores as intermediates for metal magnesium production

Bekényiová Alexandra, Danková Zuzana, Kollová Zuzana, Fedorová Erika, Bačo Pavel, Briančin Jaroslav, Čechovská Katarína

Geology, Geophysics and Environment

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2025

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Vol. 51, no. 2

193--203

EN

The current work investigates the differences between four types of calcinated dolomite samples as suitable intermediates for subsequent silicothermic reduction of metal magnesium by simultaneous differential thermal analysis (DTA) /thermogravimetric analysis (TG). The results of the DTA/TG analysis showed the least significant differences at the temperature endotherms with no weight loss on the TG curves at a temperature of 1373 K for the calcined dolomite sample TR-1 from Trebejov deposit. The most significant difference on the DTA curves was detected for the calcinated sample KRA-1 (deposit Kraľovany), which is connected with the hydration activity of the sample. According to the results of the chemical analyses, annealing products of all samples fulfilled two of the three conditions, namely a molecular ratio of CaO:MgO and an impurity content below 2.5% for their subsequent use as feedstocks in the silicothermal process for the preparation of metallic magnesium. Subsequently, the experimental test of silicothermic reduction of magnesium of calcinated sample ST-1 in a flowing argon atmosphere was investigated by EDX analysis. The results indicate that the prepared magnesium sample analysed by EDX – point and mapping analysis confirmed the presence of magnesium totalling 91% despite the failure to reach the temperature in the furnace required for the reduction of Mg.

4

Pułapki gazowe w dolomitach pierwszego cyklotemu cechsztyńskiego w kopalni rud miedzi Rudna (KGHM Polska Miedź S.A.)

Poszytek Anna, Rybak-Ostrowska Barbara, Łukaszewski Paweł, Sidełko Michał

Przegląd Geologiczny

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2024

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Vol. 72, nr 11

636--645

EN

Gas traps occurring at the top of the Rudna copper mine workings are composed of dolomites with different reservoir properties (dolosparites with high reservoir properties Dsh, dolosparites with low reservoir properties Dsl and dolomicrites with the properties of a sealing rock Dm). All the dolomites can accumulate gas; however, Dsh has the greatest reservoir potential due to its high porosity and permeability. The irregular distribution of individual dolomite facies in the rock mass causes small tight traps. Gas can be released from traps by failure of the rock structure. as a result of even small changes in the stress field caused by mining operations. The latter trigger the stress wave that can propagate across the rocks mass. The stresses can accumulate at the borders of Dsl and Dm facies of high strength constituting a barrier, and Dsh of low strength that is prone to failure. The random distribution of dolomite facies may explain the irregular gas flows into the boreholes monitoring the presence of gas at the top of the excavations.

5

CO2 bubble formation on dolomite surface and its influence on surface wettability and flotation of dolomite

Li Xianbo, Zhang Qin, Chen Aoao, Wang Xuming

Physicochemical Problems of Mineral Processing

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2024

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Vol. 60, iss. 3

art. no. 190254

EN

Dolomite is a common carbonate mineral that can release CO2 gas under acidic conditions. The formation of bubbles on the dolomite surface might play a critical role in the flotation separation of dolomite from apatite. In this study, the CO2 bubbles formation due to CO2 gas releasing from the dolomite surface under acidic condition was observed using an atomic force microscope (AFM). The influence of CO2 bubbles on flotation behavior and surface wettability of dolomite was evaluated through micro-flotation test, contact angle measurement and molecular dynamics simulation. The results indicate that no gas phase points were observed on the dolomite surface in deionized water or sodium oleate (NaOL) solution. CO2 nanobubbles were observed on the dolomite surface treated with NaOL solution at pH 5, with an average size of 44 nm. The presence of CO2 gas layers has a shielding effect on the adsorption of water molecules on the dolomite surface, potentially enhancing the surface hydrophobicity of dolomite. Therefore, CO2 bubbles are beneficial for improving flotation recovery of dolomite. This study inspires the idea of utilizing the released CO2 bubbles in the flotation process of dolomite.

6

Morphology Analysis on Metakaolin/Dolomite Geopolymer under High Temperature Exposure

Sauffi Ahmad Syauqi, Ibrahim Wan Mastura Wan, Abdullah Mohd Mustafa Al Bakri, Ibrahim Masdiyana, Ahmad Romisuhani, Zaidi Fakhryna Ahmad

Archives of Metallurgy and Materials

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2024

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Vol. 69, iss. 4

1439--1443

EN

This paper presents the morphology of the metakaolin/dolomite geopolymer after being exposed to high temperature and compare the findings with the morphology that has not been exposed to the temperature. The geopolymers were exposed at temperatures from 200°C up to 800°C. The geopolymer was a constant mix of 90% metakaolin and 10% dolomite with 10 NaOH molarity, 0.8 solid to liquid ratio, and 2.0 by mass of alkaline activator. The morphology of geopolymer exposed to high temperature contains many pores and as the temperature rises, the pores become huge, and a higher quantity of pores can be observed. The surface analysis, compressive strength, and water absorption test were also done to support the findings. The compressive strength calculation was based on weight loss. The lowest compressive strength loss was at 200°C temperature exposure with 10.98%. Meanwhile, the highest compressive strength loss was at 800°C temperature exposure with 48.54%. In comparison, this metakaolin/dolomite geopolymer archive better properties compared to the concrete and metakaolin past studies.

7

Effects of Dolomite Geopolymer Filler on Mechanical Properties of Glass Fibre Reinforced Epoxy Composite

Shahari Shazzuan, Ghazali Mohd Fathullah, Abdullah Mohd Mustafa Al Bakri, Tan Ch. Lih, Faheem Mohd Tahir Muhammad, Darmawan Vertic Eridani Budi

Archives of Metallurgy and Materials

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2024

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Vol. 69, iss. 3

1245--1249

EN

The effect of the incorporation of dolomite based geopolymer on the tensile and flexural properties of glass fibre reinforced epoxy composite were investigated. Composites containing different weight percentages of fillers (2.5, 5.0 and 7.5 wt.%) were fabricated using hand lay-up and vacuum bagging techniques. The experimental results showed that the dolomite based geopolymer contributed to the detrimental effect on tensile strength of the composite with 2.5 wt.% incorporation of the filler contributed to the least detrimental effect. 2.5 wt.% incorporation of dolomite based geopolymer meanwhile improved flexural strength by 13.04%.

8

Effect of Nitrate Acid Treated Dolomite on the Tensile Properties of Ultra-High Molecular Weight Polyethylene (UHMWPE) Composites

Abdullah Siti Fatimah Azzahran, Saleh Siti Shuhadah Md, Mohammad Nur Farahiyah, Mahamud Syarifah Nuraqmar Syed, Omar Mohd Firdaus, Akil Hazizan Md, Chang Boon Peng, Saliu Hafsat Ronke, Rostam Nurizatul Husna, Gondro Joanna

Archives of Metallurgy and Materials

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2024

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Vol. 69, iss. 1

281--288

EN

Ultra-High Molecular Weight Polyethylene (UHMWPE) polymers have been used in biomedical applications due to its biocompatibility, durability, toughness and high wear resistance. To enhance the mechanical properties, various types of minerals are commonly utilized as fillers in UHMWPE. One of the minerals is dolomite, which has been recognized as a valuable mineral with versatile applications, particularly in the field of biomedical applications. This paper presents the tensile properties of UHMWPE composites that filled with dolomite and treated-dolomite at various filler loading (i.e., 1-5 wt.%). Nitric acid and diammonium phosphate were used to treat the dolomite. From the results, the peaks of the FTIR spectrum displays carbonate (CO3-2), phosphate (PO4-3) and hydroxyl (OH-) groups in the ct-dolomite powder sample while the XRD pattern reveals that using dolomite treated with 1M nitric acid resulted in the presence of calcium hydroxide phosphate (Ca10(PO4)5(OH)) and MgO. For tensile strength, UHMWPE/ct-dolomite composites show better tensile strength than the pure UHMWPE composites. Treated improve the dolomite filler and resulted in significantly better matrix-filler interfacial interactions and improve the properties.

9

Wpływ dodatku surowców pochodzenia organicznego na wytrzymałość mechaniczną granulatów na bazie dolomitu

Jóźwiak Marcelina, Pankalla Ewa, Hoffmann Józef, Braun-Giwerska Magdalena

Chemik

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2023

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Nr 1-4

50--54

PL

Przedstawiono wyniki badań procesu granulacji mączki dolomitowej z dodatkiem surowców pochodzenia organicznego, w tym biomasy odpadowej. Zbadano wpływ takiego rodzaju dodatku na wytrzymałość powstającego w procesie granulatu. Oceniono jakość wytworzonych produktów oraz przebieg procesu aglomeracji na podstawie wyników analizy sitowej oraz badania wytrzymałości mechanicznej granul na zgniatanie.

EN

The results of the granulation process of dolomite flour with the addition of organic raw materials, including waste biomass, are presented. The influence of this type of additive on the strength of the granulate produced in the process was investigated. The quality of the manufactured products and the course of the agglomeration process were evaluated on the basis of the results of the sieve analysis and the mechanical strength test of the granules.

10

Rock transport after an outburst and the fluidisation phenomenon – can it occur during a dolomite and gas outburst?

Kozieł Katarzyna, Skoczylas Norbert

Archives of Mining Sciences

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2023

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Vol. 68, no. 4

621--638

EN

Rock and gas outburst is a phenomenon in which fragmented rock material is transported deep into a pit. The transport of rock material by gas is a two-phase process. The article deals with the fluidisation of rock material. Considerations on the fluidisation phenomenon were carried out, and experiments were performed to help clarify whether the fluidisation of dolomite is possible. In the last chapter, a discussion was carried out, and the results obtained were analysed regarding the possibility of occurrence in mine conditions.

11

Wpływ roztworów lignosulfonianów na granulację mączki dolomitowej

Jóźwiak Marcelina, Pankalla Ewa, Kubica Weronika, Kozioł Krzysztof, Huculak-Mączka Marta, Nieweś Dominik, Biegun Marcin, Hoffmann Józef

Przemysł Chemiczny

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2022

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T. 101, nr 6

409--413

PL

Przedstawiono wyniki badań procesu granulacji mączki dolomitowej z zastosowaniem wody oraz roztworów lignosulfonianów sodu i wapnia jako cieczy zwilżającej. Zbadano wpływ poszczególnych parametrów granulacji na przebieg procesu oraz właściwości fizykochemiczne otrzymanych granulatów. Oceny jakości wytworzonych produktów, jak i przebiegu procesu dokonano na podstawie wyników analizy sitowej oraz badania wytrzymałości mechanicznej na zgniatanie.

EN

Dolomite was moistened with aq. solns. of Na or Ca lignosulfonate (concs. 1−30% by mass) and granulated in a disc granulator for 1−60 min. The sieve anal. and the mech. strength tests for crushing of granules were performed. Higher values of crushing strength were obtained in the case of granulation of dolomite with the use of Na lignosulfonate.

12

Ocena bezpieczeństwa wytwarzania i magazynowania nawozów na bazie dolomitu i azotanu(V) amonu z dodatkiem substancji organicznych

Jóźwiak Marcelina, Pankalla Ewa, Marecka Kinga, Biegun Marcin, Hoffmann Józef

Przemysł Chemiczny

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2022

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T. 101, nr 10

834--839

PL

Przedstawiono ocenę zagrożenia bezpieczeństwa procesowego wytwarzania i przechowywania nawozów o wysokiej zawartości dolomitu z dodatkiem azotanu(V) amonu. Do mieszanek nawozowych zastosowano dodatek lignosulfonianu sodu lub wapnia, który miał na celu ułatwienie i usprawnienie procesu granulacji. Obydwa dodatki silnie zwiększały zagrożenie bezpieczeństwa wytwarzania i pozostałych operacji z mieszankami zawierającymi azotan(V) amonu. Wysoka zawartość dolomitu nie niwelowała niekorzystnego działania lignosulfonianu sodu i wapnia. Badania wykonano metodą analizy DTA/TG.

EN

Na or Ca lignosulfonate in an amt. of 3.2 and 3.0% by mass, resp., was added to the dolomite mixts. with NH₄NO₃ and studied by DTA/TG. Both additives significantly increased the safety risk during the production and storage of fertilizers with mixts. contg. NH₄NO₃. The high content of dolomite did not eliminate the adverse effects of Na and Ca lignosulfonate.

13

Selective depression of Escherichia coli on flotation of collophanite and dolomite

Li JiaXin, Nie GuangHua, Jiang Ying, Luo GuoJv, Li Jie

Physicochemical Problems of Mineral Processing

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2022

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Vol. 58, iss. 4

art. no. 150604

EN

The phosphate rock flotatio n test was carried out using Escherichia coli E. coli ) as a depressant of dolomite. The results showed that E. coli had a great selective depression on dolomite during flotation. With E. coli as a depressant of dolomite, a useful beneficiation index of phosphorus concentrate with P2O5 grade of more than 30% and MgO content less than 1.2% can be obtained by closed circuit of one stage roughing and one stage cleaning. Furthermore, the depression mechanism of E. coli was studied by ad sorption experiments, infrared spectrum, and zeta potential. This study shows that the adsorption ability of E. coli onto dolomite is stronger than that of collophanite. When the pH is greater than 6, E. coli are chemically adsorbed on the surface of the c ollophanite and dolomite,which also increases the negative charge on the surface of the two minerals. The selective adsorption of E. coli cells to dolomite was best when the pH value is about 7.8.

14

Reverse anionic flotation of dolomitic collophanite using a mixed fatty acid collector : adsorption behavior and mechanism

Xu Wei, Liang Qun, Tian Yan, Mei Guangjun

Physicochemical Problems of Mineral Processing

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2022

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Vol. 58, iss. 4

art. no. 151519

EN

Collophanite in south China generally has a high MgO level, which negatively impacts wet-process phosphoric acid production and cannot be utilized directly. A novel mixed fatty acid soap (GSWF01) was employed as a collector for dolomite. A single reverse flotation experiment was performed on a dolomitic collophanite from Guizhou, China under different pH and collector dosages. A phosphate concentrate with P2O5 grade of 33.73%, MgO content of 1.07%, MER value (ω(MgO+Al2O3+Fe2O3)/ω(P2O5)) of 4.86% and phosphorus recovery of 91.06% was obtained. The beneficiation indexes of GSWF01 were better than that of sodium oleate (NaOL). The adsorption behavior and mechanism of GSWF01 on dolomite surface were investigated using quartz crystal microbalance with dissipation (QCM-D), atomic force microscope (AFM), infrared spectrometer (IR), and zeta potentiometer. The results revealed that GSWF01 chemically reacted with metal ions (Ca2+, Mg2+, etc.) on the surface of dolomite to generate fatty acid salt precipitation (chemisorption). The adsorbed layer transitioned from dense to loose in two stages, resulting in a stable double-layer adsorption structure. Moreover, in a weak acidic solution environment, physical adsorption of fatty acid molecules (RCOOH ((aq)) and fatty acid ion-molecular association compounds (RCOOH• RCOO-) generated by hydrolysis can also occur on the dolomite surface. These are the main reasons for the hydrophobic floating of dolomite. This is of great significance to the development of a novel high-efficiency dolomite collector and the enhancement of flotation process for carbonate collophanite.

15

Research of nanobubbles enhanced reverse anionic flotation of a midlow grade phosphate ore

Zhang Tiebin, Zhang Qin

Physicochemical Problems of Mineral Processing

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2022

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Vol. 58, iss. 1

113--125

EN

The reverse anionic flotation is commonly used to upgrade the mid-low grade phosphate ore in China. The mineral characterization of raw ore shows that carbonate and phosphate minerals combined with fine intergrowth, difficulty in upgrading. Flotation using nanobubbles (NBs) can significantly enhance the flotation efficiency of fine particles of minerals. To research the effect of NBs on the flotation process of this phosphate ore, two flotation tests with and without NBs were compared. The results show that the MgO removal had an increment of 10% in the case of NBs flotation versus conventional flotation in the approximate grade and recovery of P2O5. The foam product of NBs flotation had smaller dimensions than the conventional flotation. NBs enhanced the contact angle on dolomite surface from 45.8° to 64.5°, and increases the d50 of dolomite from 20.49 µm to 30.43 µm.

16

Effect and mechanism of depressant CK102 on flotation separation of fluorite and dolomite

Li Zhengyao, Wang Xuewen, Xu Chengyan, Sun Tichang, Liu Weiran, Wei Jinzhi

Physicochemical Problems of Mineral Processing

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2022

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Vol. 58, iss. 3

art. no. 145796

EN

For a low grade dolomite type fluorite ore in the Hebei province, it was observed that the depressant CK102, a mixture of sulfuric acid, sodium silicate and aluminum sulfate, can effectively inhibit the gangue mineral dolomite in the flotation of fluorite. However, the inhibition mechanism of the depressant is still unclear. In this paper, the flotation separation performance and underlying mechanism of CK102 inhibiting dolomite were investigated through mineral flotation tests, adsorption measurements, infrared spectroscopy, and X-ray photoelectron spectroscopy (XPS). The flotation results showed that the inhibition effect of CK102 on dolomite flotation was much more remarkable than that of fluorite flotation under optimum conditions. Adsorption measurements revealed that there was competitive adsorption between the depressant and collector and that the adsorption of the depressant CK102 prevented the collector modified sodium oleate from adsorbing onto the surface of minerals. The FT-IR and XPS results showed that the co-oxygen cross-linked component of the depressant CK102 chemisorbed on the surface of dolomite; the CaSiO3 precipitation was generated from the reaction of CK102 with Ca2+ groups on the surface of the dolomite; Al2MgO8Si2 precipitation was also generated from Mg2+ reacting with the sodium silicate and aluminum sulfate of CK102. The above adsorptions and reactions enhanced the hydrophilicity of the dolomite surface and the dolomite was effectively depressed.

17

A first-principle study of the effect of Fe/Al impurity defects on the surface wettability of dolomite

Chen Hong, Ao Xianquan, Cao Yang, Li Cuiqin, Jiang Chunyan

Physicochemical Problems of Mineral Processing

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2022

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Vol. 58, iss. 4

art. no. 150702

EN

The presence of Fe and Al atoms in large quantities in phosphate ores can significantly affect the surface properties of the minerals during flotation. In this study, the effects of Fe/Al impurities on the adsorption of H2O molecules on dolomite, including the density of states (DOS), Mulliken bond group values, and charge groups, were investigated and the adsorption energy was analyzed using density functional theory. The results show that the adsorption of H2O molecules on perfect and Fe/Al-substituted dolomites is weak chemisorption, and the Fe and Al impurities weaken and enhance the adsorption capacity of H2O molecules, respectively. Therefore, the hydrophilicity of the dolomite surface increases in the following order: Fe-substituted dolomite < perfect dolomite < Al-substituted dolomite. The Mulliken charge and bond group analysis shows that the adsorption of H2O molecules on dolomite is primarily through the interaction between Ow and Ca atoms, where the d orbitals of Ca atoms provide charges for Ow atoms to form ionic bonds, which related to the poor electronegativity of Ca atoms and their weak valence electron binding ability. The DOS analysis shows that, during the adsorption of H2O molecules on dolomite, Mg and Al atoms have less influence on the dolomite surface, whereas Fe and Ca atoms undergo competitive adsorption, which inhibits the interaction between Ca atoms and H2O molecules on the dolomite surface.

18

Phase Analysis of Different Liquid Ratio on Metakaolin/Dolomite Geopolymer

Sauffi Ahmad Syauqi, Ibrahim Wan Mastura Wan, Al Bakri Abdullah Mohd Mustafa, Ibrahim Masdiyana, Ahmad Romisuhani, Zaidi Fakhryna Ahmad

Archives of Metallurgy and Materials

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2022

|

Vol. 67, iss. 1

247--250

EN

Geopolymer is widely studied nowadays in various scope of studies. Some of the ongoing studies are the study of the various materials towards the geopolymer strength produced. Meanwhile, some of the studies focus on the mixing of the geopolymer itself. This paper discussed the phase analysis of metakaolin/dolomite geopolymer for different solid to the liquid ratio which was, 0.4, 0.6, 0.8, and 1.0, and the properties that affected the geopolymer based on the phases. The constant parameters in this study were the percentage of metakaolin and dolomite used. The metakaolin used was 80% meanwhile dolomite usage was 20%. Besides that, the molarity of NaOH used is 10M and the alkaline activator ratio used is 2.0. All the samples were tested at 28 days of curing. The results show that the 0.8 solid to the liquid ratio used gave better properties compare to other solid to liquid ratio. The phases analyzed were quartz, sillimanite, mullite, and faujasite. The 0.8 S/L ratio shows the better properties compared to others by the test of phase analysis, compressive strength morphology analysis, and functional group analysis.

19

Anizotropia akustyczna w utworach wapienia cechsztyńskiego (zachodnia Polska)

Poszytek Anna, Łukaszewski Paweł, Włodarczyk Marcin

Przegląd Geologiczny

|

2021

|

Vol. 69, nr 6

386--388

EN

In September2009, gas and rock were ejected from the roof of the excavation at the Rudna copper mine of KGHM Polska Miedź S.A. The ejection occurred as a result of an unsealing of a small gas trap locateda few metres above the roof of the excavation within the dolomites of the first Zechstein cyclothem (PZ1). In order to identify the nature of the reservoir rock for natural gas, microscopic observations and X-ray microtomography were performed and compared with the results of the acoustic anisotropy tests. The obtained results indicate that, based on well-recognized petrological rocks, the results of acoustic anisotropy can be successfully applied as diagnostic for the recognition of rocks of various structures, textures and porosities.

20

Reverse flotation of collophanite at natural pH using isooctyl polyoxyethylene ether phosphate as a collector

Li Hongqiang, Zhang Wen, Chen Qian, Huang Peng, Kasomo Richard M., Zou Ze, Weng Xiaoqing, He Dongsheng, Yang Siyuan, Song Shaoxian

Physicochemical Problems of Mineral Processing

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2021

|

Vol. 57, iss. 4

78--86

EN

Reverse flotation of collophanite at natural pH could significantly decrease the cost of pH regulators. In this study, isooctyl polyoxyethylene ether phosphate (AEP) was tested as a new surfactant in the reverse flotation of collophanite. Micro-flotation tests were conducted, and the adsorption mechanism of the new collector was analysed using X-ray photoelectron spectroscopy (XPS) and zeta potential analyses. The results of the flotation tests demonstrated that AEP could enable dolomite to float under natural pH (pH=7.2) and showed profound selectivity towards dolomite as opposed to fluorapatite. Based on the zeta potential and XPS results, the adsorption phenomena are mainly attributed to calcium active sites on both mineral surfaces. Dolomite possesses more magnesium active sites than fluorapatite, which tend to reinforce the interaction effect between AEP and dolomite. Furthermore, when compared to CO32- ions on the dolomite surface, PO43- ions on the fluorapatite surface tend to exhibit a stronger hindrance to the adsorption of AEP on the fluorapatite surface. This is attributed to their larger volumes and more charges on their surfaces, thereby causing a floatability difference between the two minerals.