Zircon Sand Research Articles

Structural and optical characterizations of zircon and zirconia nanopowders derived from zircon sands

This study explores the structural and optical properties of zircon (ZrSiO4) and zirconia (ZrO2) nanopowders using two types of natural Indonesian zircon sands. The former powders were synthesized through dissolution and non-dissolution methods, while the latter powders were synthesized using alkali fusion and co-precipitation techniques. x-ray fluorescence (XRF) analysis revealed a reduction in impurities post-synthesis. X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM) analyses indicated that the dissolution process yielded pure zircon, whereas the non-dissolution method resulted in the presence of minor additional phases. For zirconia, all samples exhibited a tetragonal phase, albeit with varying structures. Optical properties were investigated using UV–vis spectroscopy, which showed that both materials exhibit high absorption in the ultraviolet region, with slight differences in wavelengths peak. Consequently, zircon and zirconia demonstrated similar band gap energies ranging from 3.76 to 3.95 eV and 3.99 to 4.06 eV, respectively. Photoluminescence testing further revealed identical emission peaks 350 nm for both materials, highlighting their comparable optical characteristics. This study provides valuable understandings into the synthesis and optical properties of zircon and zirconia nanopowders derived from Indonesian zircon sands, emphasizing their potential applications in various optical and electronic fields.

POTENSI ANCAMAN HILANGNYA KANDUNGAN MINERAL ALAMI (TENORM) DI WILAYAH PENGHASIL TAMBANG KABUPATEN BANGKA TENGAH

The community in Central Bangka Regency carried out an increase in illegal mining in 2021, which could potentially threaten the loss of strategic natural resources. Rocking table miners in Central Bangka Regency produce zircon sand, tin sand, monazite, ilmenite, and tailings, which are potential natural resources containing rare earth metal elements. This research aims to analyze the radioactive content of the minerals zircon sand, tin sand, monazite, ilmenite, and tailings as a threat to human health. The research showed that monazite samples from all villages still had a lot of rare earth metals in them, like yttrium (Y), lanthanum (La), cerium (Ce), samarium (Sm), neodymium (Nd), and gadolinium (Gd). The test results showed that monazite had the highest average concentrations of Rare Earth Elements (REEs), with values of 10.27±3% for La, 12.15±3% for Ce, 24.40±3% for Sm, 7.37±3% for Nd, and 0.69±3% for Gd. For tin samples, the average (Ce) was 2.79±3%, zircon samples had an average (Ce) of 4.33±3%, and (Nd) 1.04±3%. In the ilmenite samples, the average value (Y) was 6.64 ± 3%. Monazite has the most rare earth metal elements, but it has a very low selling price. Monazite plays a crucial role in safeguarding and preventing the loss of strategic natural resources and health threats. It provides policy advice to related institutions through various roles and functions, including investigation, early prevention, and forecasting of these threats.

Effect of Temperature on Zirconia Powder Synthesized from Amang Zirconium Oxychloride Precursor

Polymorphic zirconia is economically attractive in various applications due to its low reactivity, high strength, and stability. Zirconia can be synthesized from locally available Amang zircon sand as an inexpensive green alternative as it has a high zirconium content as reported by previous report. Unfortunately, the study was only focused on the formation of zirconium oxychloride despite of high zirconium content from the improved alkali fusion method proposed. Therefore, a further study on zirconia powder calcined in varied temperatures from Amang zirconium oxychloride precursor was done. Amang zirconia powder was then characterized in order to study the effect of temperature on Amang zirconia powder. Elemental analysis showed that zirconium composition was affected by temperature and increased as the temperature increased with the highest zirconium content of 81.28 wt.% with low impurities after calcined at 800 °C for 4 hours. The phase analysis satisfied monoclinic zirconia with minor tetragonal and cubic phase with sharper peaks as calcined temperature increased. Increased tetragonal and cubic phase was observed as the temperature was increased. Morphology analysis showed zirconia powder was angular and pyramidal with large crystal size which led to high tendency of monoclinic phase. Calcination temperature of 800 °C was determined to be the most suitable temperature to calcine high purity zirconia powder using Amang zirconium oxychloride precursor.

Thermal stability of light transmission on tapered plastic optical fibre coated with PMMA/zircon composites

Abstract A study on thermal stability of light transmission on tapered plastic optical fibre (TPOF) due to PMMA/zircon composites coating has been performed. The zircon filler was obtained from purified local zircon sand. The PMMA/zircon composites were produced utilizing acetone at a temperature of 50°C. The TPOF was subjected to a dip coating procedure to apply composite coatings at varying zircon of 0, 0.5, and 1 wt.%. The characterization of light transmission on coated the TPOF, investigated at an environmental temperature range of 30 to 60°C, was conducted using an optical power meter (OPM) and a spectrometer. Based on the OPM measurements, it is known that the output power of the composite coated TPOF exhibits a high degree of linearity, even when subjected to varying environmental temperatures. The coated composite material also exhibits the capability to withstand wavelength peak shift. Therefore, it can be inferred that the composites could resist fluctuations in external temperatures. To fulfil additional objectives, the composite material can be employed as a protective layer for TPOF applications, particularly while operated at temperatures exceeding the ambient conditions.

Activation energy and crystal growth coefficient determination of t-ZrO2 using high-temperature synchrotron X-ray diffraction

Abstract Activation energy and crystal growth coefficient of t-ZrO2 (tetragonal zirconia) were determined through an in-situ synchrotron radiation X-ray diffraction (SR-XRD) experiment. The t-ZrO2 precursor was synthesized through (a) purification of zircon sand from Kereng Pangi, Kalimantan to zircon powder, (b) alkali fusion, and (c) co-precipitation. High-temperature SR-XRD experiments were carried out with varying holding times of 1, 2, and 3 hours at 900, 950, and 1000 °C, respectively, where the formation and crystal growth of t-ZrO2 were observed. The diffraction patterns show that t-ZrO2 has formed at 900°C for 1 hour and it grows accordingly. The effect of the heating temperature and holding time on the crystal growth shows that the size of hot crystals increases with increasing temperature and holding time. It is found that the activation energy of t-ZrO2, in general, decreases with holding time, i.e. from 75.3 kJ/mol (3 h) to 57.3 (1h). Meanwhile, Beck’s crystal growth coefficient value is between 0.3 at 900 °C and 0.2 at 1000 °C.

Synthesis of Environmentally Friendly Oxide Zirconium from Zircon Sand

Synthesis of Environmentally Friendly Oxide Zirconium from Zircon Sand

Characterization and Stability of ZrO2-SiO2 Nanofluids from Local Minerals Indonesia as Green Nanofluids to Application Radiator Cooling System

In the last few years, there has not been much research on green nanofluids that come from material resources such as parts of palm oil and natural zircon sand. Green nanofluids need to be developed to improve heat transfer performance. The characterization of nanoparticles made from the synthesis process and the stability of ZrO2-SiO2 Nanofluids-W/EG, different volume concentrations were investigated. The experiments carried out were characterization of nanoparticles using SEM and FTIR, the stability of green nanofluid was investigated for a volume concentration of 0.1-0.3%, using UV-Vis, Zeta potential and sedimentation observation. The results show that the size of Nano-Zircon particles of 32.984-38.465 nm and Silicate nanoparticles with of 44.002-50.444 nm. The stability of ZrO2-SiO2 Nanofluids-W/EG made with the UV-Vis method is stable up to 30 days after preparation with a sonication time of 2 hours with a value of 70-80%. The zeta potential evaluation performed for green ZrO2-SiO2 Nanofluids-W/EG obtained a value of 45.37 mV with good stability classification. Sedimentation from this visual observation obtained the absence of agglomeration after 30 days.

Sol-gel synthesis of zirconia-based nanoparticles from the side product of tin mining

Indonesia has been one of the world’s primary source of tin since the early of 19th century. Bangka island has the largest tin abundant with a side product is zircon sand (ZrSiO4). The existence of zircon (ZrSiO4) is mostly associated with some of the valuable oxide compounds (VOC) and rare earth oxides (REO). The zirconia powders were synthesized from the zircon sand of PT. Timah Tbk by caustic fusion method followed by sol-gel method. The raw material zircon sand and as-synthesized zirconia were characterized through x-ray fluorescence (XRF), x-ray diffraction (XRD), surface area analysis and porositymeter, thermogravimetric and differential scanning calorimetry analysis (TG-DSC), fourier transform infra-red (FTIR) and scanning electron microscopy (SEM) techniques. The results show that zircon sand from PT Timah Tbk contains some of VOCs, such as ZrSiO4, ZrO2, HfO2, SiO2, Al2O3, TiO2, Fe2O3 and some REOs, such as La2O3, Y2O3, Nb2O5. The fusion temperatures varied from 600 to 800 °C which resulted in an increase of the purity of ZrO2 to 76% based on the XRF analysis. The surface area analysis and porositymeter results showed the significant change in specific surface area, pore size and pore volume of as-synthesized zirconia. The specific surface area increased dramatically from 0.28 m2/g to 173.97, 125.18, and 102.14 m2/g, at fusion temperatures of 600, 700, and 800 °C, respectively. The average particle size of as-synthesized zirconia showed the significant change from 21.31μm to 34.48 nm. The results of this work open new opportunities for the development of zirconia-based nanoparticles from the side product of tin mining.

EXPERIMENTAL SYNTHESIS OF ZIRCONIA NANOPARTICLES USING VARIOUS CAUSTIC FUSION TEMPERATURES DERIVED FROM NATURAL MATERIAL ZIRCON SAND IN INDONESIA

The purpose of this research was to analyze the effect of caustic fusion temperature on the size, and impurity of Nano-zircon produced from zircon sand. Caustic fusion of zircon sand using NaOH was conducted with varied temperatures of 400-600 °C, followed by water leaching, acid leaching, precipitation, and calcination to produce zirconia nanoparticle powder. The synthesized zirconia nanoparticle was analyzed using FT-IR and SEM. The yield of the product was also determined and the correlation between varied caustic fusion temperature and yield and diameter product was determined using the least square equation. From the FT-IR spectrum, it is shown that the presence of -OH hydroxyl groups at a wavelength of 3417.725 cm-1 indicates the presence of ≡Si-OH groups. At wave 2258.504 cm-1 indicate the presence of a Si-H group in the form of ≡Si-O-OH groups. The correlation between the temperature of caustic fusion and yield follows the equation y = -0.00184x + 1.244 and R2 = 0.9888 indicating that the higher the temperature of caustic fusion the higher the yield of zirconia nanoparticle product. The optimum temperature was found at 450 °C with a yield of 0.42% and a size of 32.984 nm.

THE DEVELOPMENT OF A PROTOTYPE OF LOW-TENORM ZIRCONIUM OXYNITRATE HYDRATE PRODUCTS FROM LOCAL ZIRCON, WEST KALIMANTAN

Zirconium Oxynitrate Hydrate (ZrO(NO3)2·xH2O) prototype product from Kalimantan zircon sand, or hereafter we mention it as ZON, has been successfully synthesized. The ZrO2 content of 38.62 wt.% in the ZON analysis was higher than that of several commercial products. TENORM (Technologically Enhanced Naturally Occurring Radioactive Material) reduction was obtained from zircon raw materials containing ThO2 and U3O8 of 619.9 and 728.8 ppm, respectively, to become 121.1 and 0 ppm in the ZON. The ZON formation was indicated by the XRD and FTIR characterization.

The Effect of Leaching Time on ZrO<sub>2</sub> Synthesis through Alkali Fusion and Acid Leaching

Zircon (ZrSiO4) is one of Indonesia's most abundant mineral reserves that have yet to be fully utilized since zircon mine production in Indonesia is only 110.000 tons/year while Australia produces zircon up to 500.000 tons/year. Indonesia has 167 million tons of zircon sand reserves, especially in West Kalimantan. One of the most efficient methods of zircon sand processing in terms of energy use and environmental pollution is the alkali fusion of NaOH. This study used zircon sand with NaOH, a stoichiometric ratio of 1:4 (excess 1.5), to be roasted in a muffle furnace at 600°C for 120 min. The following process is washing the frit with water, and the frit is dissolved with aquades with ratio frit: H2O=1g:10 ml at 30°C and stirring 300 rpm for 60 min. The frit leaching solution is filtered to obtain Na2ZrO3. The water-wash product is leached using HNO3 as the leaching agent with the ratio of water-wash product: HNO3=1:5, the acid concentration is 6 M, at 90°C, agitation use 260 rpm with the variation of time 60, 120, 180, 240, and 300 minutes. The pregnant leach solution is deposited with NH4OH and calcinated. According to the results of this experiment, the optimum time to obtain high Zr extraction is 240 minutes. This research produced single-phase zirconia with a cubic crystal structure containing 91.23% ZrO2 and 1.18% SiO2.

Analysis of the thermal shock and fouling resistance of the Kalimantan zircon based hybrid composite ceramic coating in boiler environment

Power plant boilers operate at relatively high temperatures and pressures. As they are prone to material degradation, fouling and scaling, the materials used must have good thermal and chemical resistance. Coating material is one of the solutions to problems that exist in boilers. In this study, the basic coating material used came from local mineral resources, namely Kalimantan zircon sand and zirconia that had been purified from zircon sand. And there is the addition of filler as a coating reinforcement so that the coating properties become better. The variables of this study are variations of filler materials that have lubricating properties such as hBN, MoS2, graphite and a mixture of the three fillers (hybrid). The coating method used is slurry spray coating and then sintering at 600 °C. The main coating parameter tests carried out were thermal shock and anti-fouling resistance. From the research results, it was found that the purification of Zircon Sand resulted in an increase in Zirconia content from 59 % to 68 %. From the results of the thermal shock resistance and anti-fouling tests, it was found that the coating with purified zircon has better thermal shock resistance while the fouling resistance is not significantly different from unrefined zircon sand, so it is necessary to develop a zircon purification process to obtain a higher ZrO2 content. For filler variations, the hybrid filler produces a coating with better thermal shock and anti-fouling resistance so that it can be used for optimizing ceramic composite coatings

Physical properties of zircon‐filled poly(methyl methacrylate) composites following heating around its glass transition temperature

AbstractZircon‐filled poly(methyl methacrylate) (PMMA) composites were synthesized, and their physical properties after ambient heat treatments were investigated. The sub‐micron zircon filler was obtained by purifying local zircon sand. The heat treatments were at 25°C (untreated), 55°C, and 70°C, around the glass transition temperature of PMMA. The crystal and molecular structures of the samples were investigated using X‐ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. The thermomechanical, optical, and thermal (between RT and 550°C) properties of all composites were examined using dynamic mechanical analysis (DMA), UV–Vis spectroscopy, and differential thermal/thermogravimetric analysis (DT/TGA) instruments. XRD patterns showed that there were no crystal structure changes. FTIR peaks were reduced due to the heat treatment indicating the presence of PMMA molecular degradation in the heat‐treated samples. Meanwhile, DMA data showed that the heat‐treated samples exhibit a much lower room temperature storage modulus, that is, up to half as compared to the untreated ones. Furthermore, the heat treatment also affects the optical properties, including a slight drop of transmittance in UV‐A and visible regions but a slight increase of transmittance in UV‐B and UV‐C regions. Finally, the differential scanning calorimetry/thermogravimetry (DSC/TG) data show that the heat‐treated pure PMMAs become more challenging to undergo thermal degradation (i.e., mass drop).

Temperature and Molarity Effects on the Synthesized Zircon Crystal Cells

A study was carried out on the effect of hydrochloric acid (HCl) temperature and molarity during the dissolution process on the crystal cell of ZrSiO4 of zircon powders derived from zircon sand mined in Kereng Pangi, Central Kalimantan. The study is a continuation of the previous work and is aimed at associating the process and structural parameters of the zircon phase in the product. The synthesis was started with a well-established route in our laboratory, i.e., magnetic separation and milling for 2 hours, but the subsequent leaching using the HCl step was carried out at varying temperatures and concentrations. The temperature variations used were 80°C, 90°C, and 100°C, while the molar variations of HCl were 0.5 and 2 M. Then, the various products were further leached using 7 M sodium hydroxide (NaOH) to yield zircon powders subjected to X-ray diffraction (XRD) investigation. The XRD data analysis using Rietica software found that at the concentration of 0.5 M, the increasing temperature decreased in zircon cell volume but increased the tetragonality parameter c/a. However, opposite results occurred at the concentration of 2 M HCl. In general, we found that the impurity levels in the zircon powders may be associated with its cell volume and tetragonality parameters, i.e., the more the quartz content in the zircon powder, the smaller the zircon cell volume and tetragonality.

Characterization of Nigerian Zircon Sand and Its Suitability for Different Industrial Applications

This paper describes the potential industrial use of zircon from Nigeria (Plateau, Nasarawa, Kano, Kaduna, Bauchi, and Adamawa states). Different techniques, equipment, and indices such as scanning electron microscope, energy dispersive X-ray fluorescence, X-ray diffraction, Fourier transform infrared spectroscopy, specific gravity, refractive index, pH, and hardness were used to examine the samples. The X-ray diffraction showed predominantly quartz, zirconium oxide, and other heavy minerals. All twelve samples showed the presence of Zr-O, SiO42−, Zr-OH, and OH, with pH values ranging from 7.3 to 7.8. Six of the zircon samples had a refractive index between 1.4 and 12.5. The hardness values ranged from 0.0021 to 0.0703 GPa, while the elastic moduli were between 0.00558 and 0.9593 GPa. Four of the twelve untreated zircon samples with specific gravities above 4.2 g/cm3, which is the United States Geological Survey minimum recommended standard for zircon sand, needed to be upgraded to increase the ZrO2 weight percentages and purity toward improving their suitability for zircon-reinforced composites applications in aerospace and also for ceramic, foundry, building and construction, and refractory industries. The study’s findings can be incorporated by the industries into their businesses for the development of novel industrial materials as well as the processing methods and procedures for beneficiation of the mineral for value-addition.

Understanding the effect of metamictization on the efficiency of zircon milling

Six commercially available zircon sands were characterised by XRD, SEM, BET and helium pycnometry to determine their degree of metamictization. These sands were categorized into pairs denoted as high, medium or low levels of metamictization. The six samples were subsequently dry milled under identical conditions and their milling behaviour was tracked by measuring the particle size distribution at regular intervals. Samples with low levels of metamictization were found to achieve a marginally smaller particle size than samples with high levels of metamictization after prolonged milling. This was attributed to two potential mechanisms during breakdown – brittle fracture in the former due to retained hardness, in comparison to a more ductile resistance to fracture in the latter due to reduced hardness. However, no clear trend between specific metamictization characteristics and milling behaviour was found. The results reveal a poorer overall milling efficiency for high metamict samples, which has implications such as increased energy costs, poor quality product and a need for further processing of samples exhibiting high levels of metamictization. This study creates a novel link between the milling behaviour of zircon and its level of metamictization. The knowledge gained holds strong importance for industrial entities wishing to carry out and maintain an efficient milling process, with feed material quality likely to become more variable in future years.

Experimental study on RPC containing zircon sand and sillimanite at elevated temperatures

The main purpose of this project involves investigation of Reactive Powder concrete (RPC), known for its ultra-high strength and improved durability properties and the influence of elevated temperatures compared with that of standard water cured samples in RPC. The process of binding is taken care by high alumina cement. The various material propositions of RPC includes Quartz sand, zircon sand, sillimanite and alccofine were used to achieve low level porosity with dense concrete matrix, thereby eliminating the addition of coarse aggregates. Micro steel fiber were used to improve the tensile property in concrete composite. The workability of concrete is improved based on poly carboxylate based super plasticizer. The experimental investigation comprises of eighteen specimens were cast and its compressive strength was observed. The samples are said to the replacement of cement with that of HAC and Alccofine in a constant ratio. The fine aggregate are being replaced completely by quartz sand, zircon sand and sillimanite with varying ratio. The samples undergone standard water curing and heat treatment at temperatures 150 °C, 300 °C, 450 °C and 600 °C. The comparative results between the standard water curing and heat treatment is observed for varying ratio of fine aggregate along with micro steel fiber and super plasticizer and the results are recorded.

Propiedades del concreto de nano-alúmina con arena de circón como finos bajo variadas temperaturas elevadas

Los materiales de construcción de hormigón ahora se juzgan no solo por sus características económicas sino también por su capacidad de servicio. Los avances en la producción de hormigón ahora también se centran en mejorar el comportamiento resistente al fuego del hormigón. La sustitución de los áridos finos es mucho más deseable cuando estos poseen adecuadas características de resistencia al fuego. El presente trabajo de investigación comprende la urgente necesidad de prestar atención al comportamiento resistente al fuego del concreto minimizando al mismo tiempo el uso del agregado Natural River. Además del reemplazo de agregados finos, la nanoalúmina se usa como aditivo de cemento para respaldar de manera beneficiosa la durabilidad del concreto a través de sus características nanométricas. La arena de circón se usa hasta en un 50 % del agregado de arena de río natural y la nanoalúmina se usa en un 2 % en peso del aglomerante de cemento. Este trabajo de investigación se enfoca en la utilización de arena de zircón como agregado fino para producir concreto.

Structures and electric properties of PANI/polymorphic-ZrO2 composites.

A polyaniline/zirconia (PANI/ZrO2) composite has been successfully synthesized using an in situ method with HCl used as a doping agent, SDBS as a surfactant and APS as an oxidant. The filler variations were comprised of various phases, which are amorphous, tetragonal, monoclinic and a mixture of tetragonal-monoclinic and varied volumes of 0, 2.5, 5.0, 7.5 and 10%. Amorphous, tetragonal and a mixture of tetragonal-monoclinic ZrO2 were obtained from purifying natural zircon sand (ZrSiO4), while monoclinic ZrO2 was obtained from commercial materials. The structure characterisation was performed using X-ray diffraction and Fourier Transform Infrared (FTIR). The morphology was observed using a Scanning Electron Microscope (SEM). The electrical properties of impedance, dielectric constant and dielectric losses, and electrical conductivity were characterised using Electrochemical Impedance Spectroscopy (EIS). The research results showed that the filler phase had an effect towards the electrical properties of PANI/ZrO2. The impedance of PANI as well as PANI/ZrO2 showed a constant phase element (CPE) behaviour with impedance values of 9.87, 9.16, 13.31, and 79.59 kΩ for the composites with amorphous filler, monoclinic filler, tetragonal filler, and tetragonal-monoclinic filler, respectively. The dielectric constant and dielectric losses decreased with the increasing amount of ZrO2 filler. The AC conductivity of PANI/ZrO2 was found to be lower when compared to PANI for all of the filler phases and volume fractions.

Influence on Ratio of NaOH/ZrSiO4 in Alkali Fusion for Amang Zircon Sand

Amang Zircon Sand from Amang Onn Sdn. Bhd. mineral company has a high composition of zirconium at 61.63 wt% and low silicon composition at 4.90 wt%. The high composition of zirconium in Amang zircon sand indicates the possibility to synthesise it into a zirconia. Zirconium was synthesised using alkali fusion method with different ratio of NaOH/ZrSiO4 to determine the optimum ratio based on the zirconium yield. Alkali fusion method is coupled with thermal treatment as it will produce a higher yield of zirconium with lower impurities. Then it will be leached with deionised water and hydrochloric acid (HCl). The synthesised zirconium was characterised through X-Ray fluorescence (XRF) spectroscopy, X-Ray diffraction (XRD) and particle size distribution (PSD) analysis. The XRF analysis after the fusion and thermal treatment shows a high composition of zirconium as well as great reduction of silicon. 1.2NaOH/ZrSiO4 is determined to be the optimum ratio as it has the lowest silicon impurity of 2.11 wt% and high yield of zirconium at 71.40 wt%. The low impurities will reduce the chance of cracking and maximising the efficiency of zirconia. It is supported by XRD patterns that are dominated by high zirconium peaks. The zirconium oxychloride obtained after acid leaching has a high zirconium composition. This shows that it is possible to use Amang zircon sand as a precursor to synthesis a zirconia using alkali fusion method with sodium hydroxide.