Colemanite Ore Research Articles

Dissolution behavior and kinetic investigation of in solution in the reaction of colemanite ore with propionic acid

Colemanite ore, which is one of the most significant commercially substantial boron minerals, is used to produce various boron compounds in the industry with its rich B_2 O_3 content. Calcium propionate, used in the food industry, is formed as a by-product in its production. In the production of boric acid from colemanite, the use of different solvent reagents is at the forefront to prevent the formation of Mg^(2+), Ca^(2+) and SO_4^(2-) impurities and borogypsum by-products. For this reason, in our study, the dissolution kinetics of colemanite ore in propionic acid solution in an aqueous medium were carried out in a batch reactor system. As dissolution parameters; reaction temperature, solid/liquid ratio, propionic acid (CH_3 CH_2 COOH) concentration, stirring speed and particle size were selected as. According to the experimental results, the amount of Mg^(2+) passed to the solution; was observed that the solution increased with the increase in reaction temperature with the decrease in solid-liquid ratio, grain size, and acid concentration. In addition, it was determined that the mixing speed was not effective. Obtained experimental data were analyzed according to homogeneous and heterogeneous reaction models using the Statistica 10.0 package program. It was determined that the dissolution kinetic of Mg^(2+) passing to solution conformed to the "Avrami model" and activation energy (E) was calculated as 8.18 kJ⁄mol.

Dissolution behavior and kinetic investigation of 〖Ca〗^(2+) in the dissolution of colemanite in propionic acid presence saturated with synthetic flue gas

Colemanite (〖2CaO.3B〗_2 O_3.5H_2 O) is a calcium borate mineral and can be expressed as the primary material of industrial production of boric acid. Boric acid is one of the most essential raw materials obtained by solving colemanite ore in acidic solutions and gases. The dissolution behavior and kinetics of 〖Ca〗^(2+) in a solution of colemanite in a propionic acid solution saturated with synthetic flue gas were examined. In this context; the effects of particle size, reaction temperature, acid concentration, solid-liquid ratio and synthetic flue gas flow rate parameters were investigated. According to the experimental data, it was observed that the amount of 〖Ca〗^(2+) passing to the solution increased with the increase of the reaction temperature, acid concentration and gas flow rate, and with the decrease in solid-liquid ratio and grain size. Experimental results were analyzed by homogeneous and heterogeneous models using the Statistica package program, and it was determined that the dissolution of 〖Ca〗^(2+) in solution complies with the “Avrami” model. The activation energy (E) was found as 〖26.83 kJ.mol〗^(-1) and the Arrhenius constant (A) was found as 〖8.9*10〗^3.

Production of boric acid from colemanite ore in the semi-batch reactor: Investigation of product yield and impurity control

Boric acid is produced by the reaction between colemanite ore and sulfuric acid in industrial processes. Since colemanite ore is not pure, various side reactions, including partial clay decomposition, can occur in the reactor medium. These reactions also lead to the presence of impurities, specifically sulfate salts. In this context, semi-batch reactors (SBR) provide selectivity, and the rate of side reactions is reduced. However, batch reactors (BR) and continuous stirred tank reactors (CSTR) have been used for boric acid production both on an industrial scale and on a laboratory scale, and the semi-batch reactor has never been used for this area. This study used SBR to minimize the side reactions rate and impurities for boric acid production. In the experimental process, a specific concentration of sulfuric acid solution was fed to the reactor at varying flow rates. The yield in the SBR increased up to 99.6%, depending on the sulfuric acid feed rate. When the same conditions were applied in the BR experiment, the yield was calculated to be 90.8%. Compared with the batch reactor results, it was observed that the impurity concentration in the boric acid solution produced within the SBR decreased by 41.7% to 45.3%, depending on the feed rate. Consequently, the utilization of SBR demonstrated clear advantages over the BR in terms of both yield and impurity control. Furthermore, this study serves as a compelling illustration of the practical applications of solid–liquid heterogeneous phase reactions within the context of SBR technology.

Estimation of the Turkish Boron Exportation to Europe

Borate is an essential material to numerous industries and even to individual countries’ economies, defense, and politics. Almost all industries need borates for production, and almost everybody needs their products. Borate is a compound that contains or supplies boric oxide (B2O3). Among the minerals that contain boric oxide, there are only four minerals significant from an economic standpoint, namely borax (tincal), colemanite, ulexite, and kernite. Turkey has almost 70% of all known reserves in the world. Therefore, borates and their products could be one of the main topics for sustainable development in the whole world. The recent development and pursuit of new boron-consuming technologies and alternative products to existing borate-consuming products introduce additional uncertainty to the sustainability of boron minerals. Therefore, the European Union (EU) Commission also declared borate one of the 30 critical raw materials. Turkey is a prosperous country in terms of boron reserves, and it exports almost 96% of borates’ production. In order to better understand the relation between borate minerals and borate products, a material flow analysis (MFA) study has been carried out within the content of this work in order to update the data about the current status of boron. For this purpose, a system has been established that shows the flow of boron material. The extraction, enrichment, and refining processes of boron products are drawn. The results indicate that about 41% of extracted colemanite ore is converted into refined borate, about 31% of tincal ore is converted to refined borate, and 4% of tincal ore is converted to end-usage products, such as detergent. The correctness of the data and the sensitivity of the processes are all estimated values. The results can help in the development of boron sustainability and boron production strategies. The MFA study on tincal and colemanite ore may be an example of boron studies in different countries.

Investigation of the interactions of arsenic with gangue minerals in colemanite calcination

In this work, the arsenic (As2O3) amount in colemanite ore was reduced from 4551 to 425 ppm using decrepitation. The crystal and amorphous states of products were determined by XRD measurements and the thermodynamic properties of samples were examined by DSC-TGA analysis. Elemental arsenic was analyzed using an ICP-ES/MS analyzer. As a result of the characterizations, a majority of the arsenic mass was found in the waste material for all temperatures. It was concluded that arsenic is carried on the surface of gangue minerals in the calcination process. Moreover, the decrepitated arsenic compounds tend to accumulate back on solid surfaces thus the amount of arsenic was found to be higher than the amount found in literature which is lower than 100 ppm. Therefore the affinity of arsenic compounds to montmorillonite and colemanite surfaces were further studied comparatively using molecular dynamics (MD) and Monte Carlo (MC) simulations. The resulting energy and density profiles show that the arsenic compounds have a higher affinity towards the montmorillonite surface. The simulation results reflect the decrease of accumulation amount on the surfaces with increasing temperature in parallel with the experimental measurements.

Effect of Colemanite Ore Wastes Utilization on Fresh Properties and Compressive Strength of Cementitious Systems

Effect of Colemanite Ore Wastes Utilization on Fresh Properties and Compressive Strength of Cementitious Systems

A Taguchi Optimization Study about The Dissolution of Colemanite in Ammonium Bisulfate (NH4HSO4) Solution

In this study, the optimum conditions of the dissolution of colemanite (2CaO.3B2O3.5H2O) ore in ammonium bisulfate (NH4HSO4) solution were examined by using Taguchi fractional design methods, and an alternative reactant for boric acid extraction process from colemanite ore was specified. The studied parameters and optimum conditions for the dissolution process were in the following; reaction temperature: 50˚C, solid/liquid ratio: 0.1 g/mL, particle size: -80 mesh, mixing speed: 600 rpm and reaction time: 25 minutes. Particle size, mixing speed and reaction time had the most significant effect on dissolution, when compared to the others. Accordingly, the dissolution efficiency of colemanite was found to be 99.54% under optimum conditions, and using NH4HSO4 as a solvent enabled the selective separation of boron from the colemanite ore. The ammonium sulphate formed as a by-product was converted into NH4HSO4 by the addition of appropriate stoichiometric amount of sulfuric acid and fed back into the dissolution vessel.

Synthesis of pure potassium pentaborate (KB5) from potassium dihydrogen phosphate (KH2PO4) and colemanite

In this study, after specifying theoretical reaction conditions required for the chemical reaction, potassium pentaborate (KB5) was synthesized from the potassium dihydrogen phosphate ( $${\text{KH}}_{2} {\text{PO}}_{4}$$ ) solution and raw colemanite ( $${\text{Ca}}_{2} {\text{B}}_{6} {\text{O}}_{{11}} \cdot 5{\text{H}}_{2} {\text{O}}$$ ) ore. The slow evaporation solution method was used at 25 °C. The effect of time (6–18 h) on crystallization was studied. Synthesized minerals were characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR), RAMAN spectroscopy, and scanning electron microscopy (SEM). The results according to XRD, FT-IR, RAMAN, and SEM analyses proved that the synthesized product was potassium pentaborate ( $${\text{KB}}_{5} {\text{O}}_{8} \cdot 4{\text{H}}_{2} {\text{O}}$$ ) mineral with ICSD: 96-026-1927 pdf code. As a result, the cost was reduced by using raw boron ore, colemanite, and KB5 was obtained in a shorter time and at a lower temperature.

High temperature resistance of concretes with GGBFS, waste glass powder, and colemanite ore wastes after different cooling conditions

Residual strength of the concrete members after being exposed to high temperatures is very important for the structures. In this study, residual strengths of the concretes produced with ground granulated blast furnace slag (GGBFS), waste glass powder (GP), and colemanite ore wastes (CW) were investigated. GGBFS and GP were used with the ratios 10%, 20%, and 30%, CW was used 1%, 3%, and 5% by weight. These 28 and 90-day cured concretes were exposed to 200, 400, 600, 800, and 1000 °C for 1 h. After this high temperature treatment, the test samples were subjected to two different cooling regimes as water-cooling and air-cooling. The residual strength of the concretes was investigated by compressive strength tests. Besides, weight losses and ultrasonic pulse velocity results were investigated as well. Surface defects of the samples were examined by the image analyze method and microstructure of the samples were evaluated by Scanning Electron Microscope (SEM) imaging. According to the results, colemanite ore waste containing concretes exhibited better performances than other series. In addition, up to 600 °C water-cooled samples had higher residual strength. This was changed in favor of air-cooling samples after 600 °C.

Thermal dehydration of colemanite: kinetics and mechanism determined using the master plots method

ABSTRACTDehydration kinetics of colemanite ore were explored using thermogravimetric analysis techniques (thermogravimetry (TG)/derivative thermogravimetry (DTG)) in the range of 0–1000°C at heating rates of 2, 5, 10 and 20°C min−1 in an inert (N2) atmosphere. Kinetic triplets which were activation energy, pre-exponential factor and reaction mechanism were obtained from the TG and DTG applying six model-free (isoconversional) methods, i.e. Kissinger–Akahira–Sunose (KAS); Flyn–Wall–Ozawa (FWO); Tang, Starink and iterative KAS and iterative FWO. The researcher tested the reliability of the study method in identifying the kinetic mechanism by comparing experimental master plots to theoretical master plots. Structural and morphological properties were carried out using X-ray diffraction, Fourier transform infrared and scanning electron microscopy-energy disperse spectroscopy methodologies.

An optimization study on dissolution of the calcined colemanite mineral in methyl-alcohol by CO2 in an autoclave system using Taguchi method

The process of optimizing the dissolution of colemanite ore (2CaO.3B 2 O 3 .5H 2 O) in methyl alcohol by CO 2 in a high-pressure reactor was evaluated by using the Taguchi method. Optimum conditions for the cholemanite mineral were determined to be as follows: reaction temperature: 140°C, reaction time: 50 min, calcination time: 240 min, calcination temperature: 450 o C, solid-liquid ratio: 1/6 g.mL -1 , mixing rate: 500 cycle/min, pressure: 20 bar, grain size: -100 mesh and the amount of CaCl 2 : 7.5 g.

Optimization of dissolution of colemanite ore in potassium dihydrogen phosphate solution (kh2po4)

Boron is one of the most important richnesses of Turkey which has approximately 72% of the known boron reserves globally. The production of boron compounds has essentially expanded recently due to increasing demands. Colemanite rich in boron is a common raw material to produce boron components and the first step of this process is the dissolution of colemanite by using different leaching solutions. The main aim of the study is to investigate the optimization of dissolution of colemanite in potassium dihydrogen phosphate ( KH 2 PO 4 ) solution. Taguchi method was used to determine the optimum conditions while effectiveness of the parameters were identified by variance analysis. Reaction temperature (T), KH 2 PO 4 concentration (C), stirring speed (W), solid to liquid ratio (S/L), and particle size (D) of colemanite were selected as parameters affecting the rate of colemanite dissolution. The optimum conditions for these parameters were determined. As a result of the experiment made under optimum conditions, both 98% of B 2 O 3 passed into the solution and potassium borate by-product were produced by crystallization.

Effect of colemanite ore as boron fertilizer on growth and yield of two wheat (Triticum aestivum L.) genotypes under field condition

Effect of colemanite ore as boron fertilizer on growth and yield of two wheat (Triticum aestivum L.) genotypes under field condition

PRODUCTION OF AN INSULATION MATERIAL FROM CARPET AND BORON WASTES

Buildings are large consumers of energy in all countries. In regions with harsh climatic conditions, a substantial share of energy goes to heat and cool buildings. This paper reports an investigation of the insulation materials made from mixing carpet wastes with a solution with added crude colemanite ore, one of boron minerals, and a solution with added colemanite wastes from a barrage. A new building insulation material was produced which is name, Halibor. Optimum mixing ratios were determined for mass production and the physical properties of the product were established. In addition, the material produced was compared with similar products used in buildings in terms of physical properties. As a result of the investigations, it was established that the product provides high heat and sound insulation and can be used easily in building and construction industry.

Kinetic Investigation of Reaction Between Colemanite Ore and Methanol

In the field of industry, it is very important that boron compounds are produced from boron ores. The aim of this study was to investigate the dissolution kinetics with carbon dioxide of colemanite in methanol medium in a pressure reactor and to derive an alternative process for producing boron compounds. Reaction temperature, stirring speed, solid/liquid ratio, pressure, and particle size were selected as parameters for the dissolution rate of colemanite. It was found that the dissolution rate increased with increase in pressure and reaction temperature, and with decrease in particle size and solid/liquid ratio. No effect of stirring speed was observed on conversion. The dissolution kinetics of colemanite were examined using both heterogeneous and homogeneous reaction models, and it was determined that the reaction rate can be described by a second-order pseudo-homogeneous reaction model. The activation energy was found to be 51.4 kJ/mol.

Adsorptive and photocatalytic removal of reactive dyes by silver nanoparticle-colemanite ore waste

A novel composite containing silver nanoparticles (AgNPs) and colemanite ore waste (COW) was synthesized and tested in adsorption and photocatalysis to remove Reactive Yellow 86 (RY86) and Reactive Red 2 (RR2) from aqueous solution in single and binary dye systems. Transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction patterns (XRD) showed the formation of metal AgNPs on COW. The BET surface area increased after intercalation of AgNPs onto COW. Ag-COW was found to be a good material for dye adsorption. The effects of operating variables such as initial dye concentration, pH and contact time in adsorption were studied. The kinetics, isotherm and thermodynamic parameters for the adsorptive removal of the reactive dyes were also investigated. In addition, Ag-COW also shows high photocatalytic activity for degradation of the reactive dyes from single and binary dye solutions. The combination of adsorption and photocatalysis using Ag-COW is demonstrated as a more effective technique for contaminant removal from aqueous solution.

Compaction and shear strength characteristics of colemanite ore waste modified active belite cement stabilized high plasticity soils

An experimental investigation was undertaken to evaluate the mechanical behavior of soil–cement mixtures. The primary motivation for the study was to investigate the innovative use of colemanite ore waste (CW) modified active belite cement (BC) in soil stabilization engineering (applications). The specific objectives of the research were to evaluate and compare: (1) compaction characteristics, (2) unconfined compressive stress-axial strain behavior, (3) unconfined compressive strength, (4) Young's secant modulus of elasticity, and (5) undrained shear strength characteristics of belite cement (BC)–clay and ordinary portland cement (OPC)–clay mixtures. BC and OPC were mechanically mixed with clay in five different dosages, i.e. 1.0%, 2.5%, 5.0%, 7.5% and 10.0% by using dry weight of clay, separately. Compaction characteristics of untreated soil, BC–clay and OPC–clay mixtures were evaluated at standard Proctor compaction energy. For a meaningful comparison of unconfined compression and triaxial test results, all specimens (untreated soil, BC–clay and OPC–clay mixtures) were prepared at maximum dry unit weight and optimum water content. Cylindrical samples of 50.0mm in diameter and 100.5mm in length were compacted in three layers and their strength characteristics were investigated at 1-, 7-, 14-, and 28-days curing times. Results of unconfined compression tests showed that cement dosage less than 5% has little effect on unconfined compressive strength (UCS) and exhibits ductile type of failure for both OPC–Clay and BC–Clay mixtures. In contrast, for cement content equal or greater than 5%, cement treatment significantly improved UCS and displayed brittle stress–strain behavior especially for BC–Clay mixtures. Similar behavior is obtained from undrained triaxial tests. The variation of undrained cohesion intercepts with respect to cement type, cement content and curing time is more sensitive than that of undrained internal friction angle.

Investigation of the Dissolution of Colemanite Ore in Water and Boric Acid Solutions Including Highly Acidic Ion Exchangers under Microwave Heating

The dissolution of colemanite obtained from Bandırma Boraks Corporation was investigated in boric acid solutions containing highly acidic ion exchangers in a classical and microwave energy heating environment and the results showed that superior conversions can be obtained via microwave heating. Particle size, acid concentration, reaction temperature, stirring speed, amount of ion exchanger, solid to liquid ratio, and microwave power were selected as parameters. Dissolution kinetics of colemanite was also examined and it was observed that the dissolution rate increased with decreasing particle size and solid to liquid ratio and increased with stirring speed, acid concentration, and amount of acidic ion exchanger. The relationship between conversion and system parameters was determined with nonlinear estimation by using the statistical program Statistica 7.0. The activation energies (E) for classical and microwave heating methods were found as 24.40 and 22.98 kJmol–1, respectively.

Use of Aspergillus niger in the bioleaching of colemanite for the production of boric acid

Colemanite is one of the most important underground riches of Turkey, having approximately 60% of the world boron deposits, and it has a large portion in the deposits. In this study, chemical leaching and biological leaching methods were used for production of boric acid from colemanite (2CaO · 3B 3 O 3 · 5H 2 O) (Emet-Kütahya, Turkey). Oxalic acid concentration, temperature, stirring time and solid-to-liquid ratio were taken as parameters in the chemical leaching process. It was found that the dissolution rate increases with increasing oxalic acid concentration and temperature but it decreases at higher solid-to-liquid ratios in the chemical leaching process. Using optimum conditions (d 100 = 0.075 mm; 5% solids by weight; 0.55 M oxalic acid; 80 ± 2ºC leaching temperature; 150 rpm stirring speed; 90 min leaching time) for colemanite sample (28.05% B 2 O 3 ) on chemical leaching with oxalic acid experiments, the calculated boric acid extraction efficiency from colemanite ore was 97.89%. Optimum conditions on bioleaching of Emet-Kütahya, Turkey colemanite ores using the fungus Aspergillus niger were found to be as follows: reaction temperature 25 ± 2 o C; solid-to-liquid ratio 5% solids by weight; d 100 = 0.075 mm; stirring speed 150 rpm; initial the fungus populations in the inocula about 3 x 10 7 cells/ml and reaction time 21 days. The calculated boric acid extraction efficiency from colemanite ore was 90.18% under the optimum conditions. Bioleachate contained 12.95 g/l B 2 O 3 , 6.60 g/l Ca and 0.087 g/l Mg. Compared with chemical leaching at 5% pulp density, the fungus was less efficient in the extraction of B 2 O 3 from colemanite but the difference in the extraction yields between the two processes was less than 10%. Although bioleaching generally requires a longer period of operation compared to chemical leaching, these results suggest that bioleaching by A. niger may be an alternative or adjunct to conventional physicochemical treatment processes of colemanite to produce boric acid.

Design parameters of boric acid production process from colemanite ore in the presence of propionic acid

In this study, three different boric acid production process alternatives which can be performed in the presence of propionic acid and/or calcium propionate were evaluated. The process in which calcium propionate is the recycling component was selected as the best alternative and modeled. Some of the design parameters were determined for the selected process. These parameters are solubility change of boric acid in the presence of calcium propionate at 25 °C, 35 °C and 75 °C, precipitation risk of calcium borate components in concentrated boric acid solutions containing calcium propionate, and the effect of calcium propionate on the solution pH with respect to free sulfuric acid concentration. According to the determined parameters, principal reactions occurred in the process, and other process parameters obtained by industrial practice, mass balances were conducted and all flow rates were calculated. In the process, calcium propionate concentration in production liquor must be kept lower than 3% and the reaction must be carried out without any free sulfuric acid in order to perform the process according to the model.