Certified reference material for gold-loaded activated carbon analyses

Abstract

The invention relates to a certified reference material (SRM) developed for use in chemical analysis laboratories in order to determine the amount of gold contained in gold-loaded activated carbon. The invention aims to increase analysis accuracy, reproducibility and the reliability of quality control processes by producing an SRM having a specific gold concentration and reflecting the porous structure of activated carbon. The invention provides economic and operational efficiency by optimising gold analysis processes in mining, metallurgy and chemistry laboratories.

Description

[0001] CERTIFIED REFERENCE MATERIAL FOR GOLD-LOADED ACTIVATED CARBON ANALYSES

[0002] Technical Field

[0003] The invention relates to the development of certified reference materials used in gold analysis. Especially, by being a reference material that accurately reflects the chemical and physical properties of a gold-loaded activated carbon matrix, it reduces the error rate in analyses. The invention provides a reliable solution in processes such as laboratory calibration, quality control and method development by increasing the accuracy and reproducibility of gold analysis methods. Thus, optimisation of gold recovery processes and industrial efficiency are achieved.

[0004] State of the Art

[0005] Gold analysis is the name given to chemical and physical analysis processes carried out for the purpose of determining the amount of gold present in a sample. Thess analyses are carried out for critical purposes such as the evaluation of gold ores in the mining sector, optimisation of gold production processes and measurement of recovery rates. At the same time, it is of great importance for determining the accuracy of ores having economic value and for ensuring quality control processes. In gold analysis, devices such as atomic absorption spectroscopy (AAS), inductively coupled plasma - optical emission spectroscopy (ICP-OES) and gravimetric methods are widely used. For example, while the AAS method is based on the principle that gold ions in solution absorb light at a specific wavelength; ICP-OES determines the concentration of gold by measuring the light emitted when it is excited in a plasma environment. The gravimetric method, on the other hand, is based on precipitation and weighing steps.

[0006] Certified Reference Materials (SRM) are materials produced and tested in accordance with international standards in order to accurately represent the amount or concentration of a specific component. SRMs are used for calibration, verification and quality control in analyses, thereby ensuring the accuracy, reproducibility and reliability of laboratory tests.These materials are produced and certified especially according to international standards such as ISO 17034. SRMs are used in many fields such as chemistry, biology, mining, environment and metallurgy. Activated carbon reference materials are SRMs that simulate the concentration of a specific component (for example gold) by taking into account the surface chemistry and porous structure of activated carbon. These materials are used especially to increase the accuracy of gold recovery and adsorption analyses on carbon. In metal analyses, SRMs provide correct calibration and optimise laboratory performance by eliminating measurement uncertainties.

[0007] The lack of certified reference materials (SRM) seriously affects the accuracy and reproducibility of analysis results. SRMs used especially in chemical analyses form the basis of calibration and quality control processes. In analyses carried out without SRM, deviations may occur in the calibration of devices and the results obtained may be erroneous or inconsistent. This situation reduces reliability in inter-laboratory comparisons and prevents the standardisation of methodologies. Especially in special matrices such as gold-loaded activated carbon, the absence of standard reference materials causes incorrect calculation of gold concentrations, which in turn leads to the inability to accurately determine recovery rates. In such a case, economic losses increase and efficiency cannot be achieved in industrial processes. In addition, performance evaluations of laboratories become unreliable and analysis results contain significant uncertainties.

[0008] The absence in the literature of a certified reference material (SRM) specifically developed for use in gold-loaded activated carbon analyses leads to significant technical and economic problems. Existing SRMs may affect the accuracy of analysis results as they cannot adequately represent the porous structure and surface chemistry of activated carbon. The lack of such a reference material in the literature leads, especially in gold recovery processes, to inter-laboratory inconsistencies, methodological errors and incorrect decision-making. In addition, due to the unique structure of activated carbon, the behaviour of gold ions in solution differs, and this situation seriously reduces the quality of analyses. The absence of such a reference material threatens the economic efficiency of the sector by reducing reliability in quality control processes. Thelack of gold-loaded activated carbon SRM not only prevents the optimisation of analysis processes but also makes it difficult for the sector to comply with international standards. The limitations and insufficiencies of the solutions in the current art, the absence of SRMs in analyses in the state of the art, the fact that analysis results differ between laboratories, the reduction of reliability in quality control processes due to the lack of SRMs and the inability to adequately represent the porous structure and surface properties of activated carbon have necessitated a development in this field.

[0009] The Aim of the Invention

[0010] The invention describes a certified reference material used in gold analyses. Especially, a reference material that accurately reflects the chemical and physical properties of a gold-loaded activated carbon matrix is produced. Existing reference materials lead to misleading results in analyses since they cannot represent the porous structure of activated carbon. The invention provides reliability in processes such as laboratory calibration, quality control and method development by increasing the accuracy and reproducibility of analysis methods, and contributes to industrial efficiency by optimising gold recovery processes.

[0011] The main aim of the invention is to provide a certified reference material in order to obtain reliable and accurate results in the analysis of gold-loaded activated carbon. Reference materials in the existing art cannot represent the unique physical and chemical properties of activated carbon. The porous structure, surface chemistry and the dynamics of gold ions in solution are of great importance in these analyses. These deficiencies lead to misleading results and inter-laboratory inconsistencies. The invention eliminates this problem by developing a certified reference material (SRM) that reflects the matrix properties of activated carbon exactly in order to accurately determine the gold content. Thus, the performance of chemistry laboratories in terms of accuracy, reliability and calibration is improved. Ensuring standardisation in analysis methods is of critical importance especially for quality control processes. The fact that existing reference materials lead to different results in gold analyses causes seriousinconsistencies between laboratories. The certified reference material that is the subject of the invention ensures that comparable and consistent results are obtained between different laboratories since it provides a solution specific to the activated carbon matrix in gold analyses. Thus, inter-laboratory performance evaluations and methodology comparisons become reliable. This situation facilitates the compliance of analyses with international standards and has a positive effect on the sector in general. In addition, incorrect analysis results lead to a decrease in gold recovery rates and to economic losses. The use of a correct and reliable certified reference material for gold-loaded activated carbon enables the gold amount to be measured in a more precise and consistent manner. This accuracy makes it possible to optimise recovery processes and to recover gold with maximum efficiency. By means of correct analysis results, incorrect decisions are prevented and the costs of enterprises are reduced. The invention provides a sustainable solution by reducing economic losses especially in the mining and metallurgy sectors. Reference materials used in existing methods may affect the accuracy of analysis results and cause errors in gold recovery rates. The certified reference material developed by the invention accurately represents the gold loading and dissolution dynamics of activated carbon. Thus, reliable results are obtained in analysis processes and recovery systems can be operated more efficiently. These optimised processes both prevent time loss and increase industrial efficiency by reducing gold production costs. Device calibrations, method development and validation studies are of great importance in order to increase the reliability of gold analyses. The developed gold-loaded activated carbon SRM increases device performance by providing a stable and accurate reference material for calibration. At the same time, it forms a basis for the development of analytical methods and the improvement of existing methods. By means of these processes, reproducible results are obtained in laboratories and measurement uncertainties are minimised. The use of this material especially in quality control studies enables laboratories to perform performance evaluations in a reliable manner. In addition to being a reliable reference material specifically for gold-loaded activated carbon analyses, the invention also has the characteristic of being a reliable reference material for all general-purpose gold analyses by means of the gold in the ash formed after the carbon content is removed by burning.Detailed Description of the Invention

[0012] The invention relates to a certified reference material (SRM) for gold-loaded activated carbon. The SRM that is the subject of the invention increases the accuracy and reproducibility of analyses and provides reliability to calibration, quality control and method development processes. Thus, industrial efficiency is achieved by increasing the effectiveness of gold recovery processes.

[0013] It is a gold-loaded activated carbon certified reference material comprising a gold-loaded activated carbon matrix with gold (Au) in a range between 1500 ppm and 2500 ppm, to be used during the determination of gold. The certified reference material that is the subject of the invention is used in gold analyses, in gold-loaded activated carbon analyses, in the calibration of laboratory devices, in quality control tests, in methodology development processes, in the mining sector, in the metallurgy sector, and in processes for the determination of gold content or optimisation of recovery.

[0014] The production method of the gold-loaded activated carbon certified reference material that is the subject of the invention comprises the process steps of

[0015] i. washing the activated carbon with a cyanide solution not containing gold, ii. subjecting the activated carbon to an adsorption process for a sufficient period of time in a cyanide solution containing gold ions until a specific concentration value is reached,

[0016] iii. subjecting the gold-loaded carbon to solid-liquid separation processes in order to separate it from the cyanide solution by filtration and drying it,

[0017] iv. applying a grinding process in order to reduce the particle size of the loaded carbon to below 150 microns,

[0018] v. homogenising the ground loaded activated carbon, and

[0019] vi. dividing the obtained homogeneous material into portions of 150 g and filling and storing it in packages in accordance with certified reference material (SRM) standards.The homogeneity properties required by the production standards of the gold-loaded activated carbon certified reference material produced by the mentioned method are controlled. Homogeneity control is carried out as specified in the ISO 17034 standard. The analysis study set designed under repeatability conditions is used for determining homogeneity. The data obtained from the study are evaluated statistically. When a non-homogeneous condition is detected, re-homogenisation and division processes are carried out in order to ensure homogeneity. This process is continued until homogeneity is achieved.

[0020] A certified reference material (SRM) is a reference material produced and tested in accordance with international standards in order to accurately represent the amount or concentration of a specific component. SRMs are used for calibration, verification and quality control purposes in various scientific, industrial and technical analyses. SRMs play a critical role in ensuring that laboratory tests and measurements are reliable and reproducible. SRMs have a standardised composition. SRMs are standardised with respect to a specific component (for example, a metal, an organic compound or a chemical element). SRMs ensure that high reliability is obtained in the analyses in which they are involved. SRMs are produced using internationally accepted methods and are analytically tested. These SRMs guarantee accuracy in laboratory analyses. SRMs are mainly used for calibration during analyses. SRMs are used in the calibration of measurement devices. Devices used in analyses are adjusted by being compared with the known values in the SRM in order to provide accurate results. SRMs are also used for quality control and verification purposes. SRMs are used in quality control processes in order to ensure the accuracy and reproducibility of analytical results. SRMs are an important tool for monitoring and verifying the performance of laboratories. By means of SRMs, compliance with international standards is achieved in laboratories. SRMs are generally produced in accordance with standards approved by ISO (International Organization for Standardization) or other international organisations (such as ISO 17034, ISO 17025, ISO 17043).

[0021] The production of a certified reference material (SRM) is a highly meticulous and standardised process. Production is carried out in accordance with internationallyaccepted standards (for example ISO 17034) and passes through various steps in order to ensure the reliability of the SRM. This process consists of the stages of material selection, homogenisation, stability tests, characterisation and analysis, certification, packaging and storage, quality assurance and traceability, and compliance with international standards. The first step in SRM production is the selection of a material that accurately represents the specific component to be analysed. This material may be a natural substance (for example soil, water, biological tissue) or a compound synthesised in a laboratory environment (for example a metal alloy or a chemical solution). The selection of the material is determined according to the type of analysis and the industry in which the SRM will be used. The selected material must contain the target components (for this reason, in the invention, the component is gold to be loaded onto activated carbon) and these components must exhibit good homogeneity and stability. After the material is selected, it is homogenised in order to ensure that all samples are analysed at an equivalent concentration. The homogenisation process ensures that the components of the material are distributed equally among the samples. This process may be carried out by grinding, mixing and dissolving or combining methods. Homogeneity is of key importance in the production of SRM, because differences between samples may adversely affect the analysis results. Stability tests are carried out in order to ensure the long-term usability of SRMs. Stability means that the material is preserved under storage conditions without undergoing chemical or physical changes. Various analyses are carried out during and after production in order to test whether the SRM remains stable over a long period of time, these tests examine the response of the material to environmental factors such as temperature, humidity and light and verify whether the samples maintain their composition over time. The target components of the SRM are determined by measurement with high accuracy. At this stage, the elements or chemical compounds in the composition of the SRM are meticulously analysed by using various laboratory methods. Characterisation generally includes the stages of multi-laboratory analysis and calibration and measurement accuracy. For multi-laboratory analysis, analyses are generally carried out by more than one independent laboratory in order to determine the correct values of the SRM. These analyses are carried out using various methodologies used by different laboratories. Forcalibration and measurement accuracy, the amount or concentration of the target components of the SRM is determined by extremely precise measurements. These measurements are of great importance in order to ensure that the SRM is used within a specific value range. After the characterisation process is completed, the SRM is subjected to a specific certification process. The certificate shows the exact amounts of the substances in the composition of the SRM and the measurement uncertainties. The certificate generally includes information on the amounts of the substances in the composition of the SRM (for example, 5 ppm gold, 3% carbon, etc.), uncertainty values and tolerance ranges, conditions of use and storage instructions, and test results related to analytical accuracy. Certification ensures that the SRM can be officially used and guarantees its reliability. SRMs must be packaged and stored under appropriate conditions in order to remain stable for a long time and not to be affected by external factors. At this stage, the samples are placed in appropriate packaging and are stored in a closed environment suitable for storage conditions. Subsequently, SRMs are generally stored in dry and cool environments, thus preventing deterioration or chemical changes over time. Quality assurance is a critical factor in SRM production. Each stage of the production process of the SRM is carefully monitored and documented. The manufacturer provides traceability and calibration reports for each batch of the SRM. These reports ensure that users can use the SRM safely. SRMs must be produced in accordance with international standards such as ISO 17034. These standards ensure the quality, accuracy and reliability of the SRM. SRM manufacturers act in accordance with these standards at every stage of the certification process.

[0022] In the report prepared in the light of this information, it is clearly seen that the 6 materials provided are not certified reference materials, but only have the property of an adsorbent material.

[0023] By means of the certified reference material (SRM) that is the subject of the invention, which is an activated carbon certified reference material loaded with a certain amount of gold, many important advantages are obtained compared to existing applications. Firstly, while the mentioned SRM fully reflects the physical and chemical properties of activated carbon, it helps to obtain reliable and accurate results in analytical processes. Whilegeneral gold SRMs may lead to misleading results since they cannot adequately represent the surface chemistry and adsorption dynamics of the activated carbon matrix, the SRMs that are the subject of the invention accurately simulate the behaviour of gold on activated carbon. In this way, consistency is ensured in analyses, reliability is increased in inter-laboratory comparisons and methodological studies are facilitated. In addition, considering the unique porous structure and surface chemistry of activated carbon, the SRM that is the subject of the invention, which reflects these properties, better imitates the physical and chemical interactions in the process of gold passing into the solution. This situation prevents incorrect interpretations in analyses and increases the reliability of processes. The use of the SRM that is the subject of the invention in gold analyses ensures that gold recovery processes are carried out more effectively and optimised. The minimisation of incorrect analysis results by the invention provides economic advantages by contributing to the increase of recovery rates and the reduction of operating costs.

[0024] The use of the SRMs that are the subject of the invention supports standardisation in the sector by improving quality control processes. The development of reference materials specific to the activated carbon matrix increases the reliability of analytical methods and reinforces the reliability of laboratory applications. In addition, these SRMs provide a solid infrastructure for the development of new analytical techniques and the improvement of existing methods. The invention makes significant contributions both to the improvement of industrial processes and to the advancement of academic research. The SRM that is the subject of the invention is suitable for use in mining production, export, import and metallurgy sectors; in all chemistry laboratories providing ore or metal analyses and quality control services, for the purpose of determining gold contents. In addition, this SRM plays an important role in processes such as quality control studies, calibration, method development, method validation and ensuring metrological traceability. Furthermore, it may also be used for various purposes such as measuring the performance of analysts or devices. It provides a wide range of applications by ensuring reliable results at different stages of gold analyses.

Claims

CLAIMS1. A reference material for use during the determination of gold, comprising a gold-loaded activated carbon matrix with gold (Au) in a range between 1500 ppm and 2500 ppm.

2. A reference material according to claim 1, for use in gold analyses, in gold-loaded activated carbon analyses, in the calibration of laboratory devices, in quality control tests, in methodology development processes, in the mining sector, in the metallurgy sector, and in processes for the determination of gold content or optimisation of recovery.

3. A method for producing a reference material according to claim 1 or 2 for use during the determination of gold, comprising the process steps of:i. washing the activated carbon with a cyanide solution not containing gold, ii. subjecting the activated carbon to an adsorption process for a sufficient period of time in a cyanide solution containing gold ions until a specific concentration value is reached,iii. subjecting the gold-loaded carbon to solid-liquid separation processes in order to separate it from the cyanide solution by filtration and drying it,iv. applying a grinding process in order to reduce the particle size of the loaded carbon to below 150 microns,v. homogenising the ground loaded activated carbon, andvi. dividing the obtained homogeneous material into portions of 150 g and filling and storing it in packages in accordance with certified reference material (SRM) standards.