Recovery of Synthetic Diamonds from Fines of Natural Stones Processing
At a Glance
Section titled âAt a Glanceâ| Metadata | Details |
|---|---|
| Publication Date | 2024-06-26 |
| Journal | Revista de GestĂŁo Social e Ambiental |
| Authors | Victor Moza Ponciano, Alexandre Vianna Bahiense, Phillipe Fernandes de Almeida, Mateus Valentim Simmer Sopeletto, Viviana Possamai Della Sagrillo |
| Citations | 1 |
| Analysis | Full AI Review Included |
Technical Documentation & Analysis: Recovery of Synthetic Diamonds
Section titled âTechnical Documentation & Analysis: Recovery of Synthetic DiamondsâExecutive Summary
Section titled âExecutive SummaryâThis research validates the high intrinsic value and durability of synthetic diamond materials by demonstrating the technical feasibility of recovering diamond micro-particles from industrial waste (Fibro) generated during natural stone processing.
- Core Achievement: Successful recovery of synthetic diamond micro-grains (0.15 mm to 0.40 mm) from rock cutting fines using a flotation methodology.
- Material Validation: The recovered diamond particles maintained an intact octahedral cube shape, confirming their high wear resistance and suitability for reuse in high-value industrial applications.
- Process Optimization: Optimal recovery rates (up to 2.91%) were achieved using specific solid concentrations (35% conditioning, 25% flotation), demonstrating process sensitivity to pulp density.
- Key Material Property: The flotation process relies heavily on the diamondâs high natural hydrophobicity, minimizing the required concentration of chemical collectors.
- Economic Impact: The study supports the circular economy model by transforming industrial waste into a high-value co-product, opening new markets for the mining and tooling sectors.
- 6CCVD Relevance: This research underscores the critical demand for high-quality synthetic diamond precursors, a market directly served by 6CCVDâs custom MPCVD Single Crystal (SCD) and Polycrystalline (PCD) materials for next-generation tooling and sensing applications.
Technical Specifications
Section titled âTechnical Specificationsâ| Parameter | Value | Unit | Context |
|---|---|---|---|
| Optimal Solids (Conditioning) | 35 | % | Percentage of solids in pulp during conditioning phase |
| Optimal Solids (Flotation) | 25 | % | Percentage of solids in pulp during flotation phase |
| Average Recovery Rate (Group 1) | 2.62 | % | Highest average recovery achieved via flotation |
| Diamond Particle Size Range | 0.15 - 0.40 | mm | Size of recovered synthetic diamond grains |
| Granulometric Classification (Mesh) | 28 - 65 | Mesh (Tyler Scale) | Material size range used for flotation (approx. 600 ”m down to 210 ”m) |
| Previous Concentration (Density/Magnetic) | 44.86 | g/t | Concentration achieved in earlier studies (Souza & Vidal, 2013) |
| Improved Concentration (Table/Density) | 60.6 | g/t | Concentration achieved with added concentrator table (Egramphonte et al., 2019) |
| Flotation Tank Volume | 2 | L | Laboratory scale flotation cell volume |
| Confidence Level (Statistical Analysis) | 90 | % | Confidence level for Pareto graph analysis |
Key Methodologies
Section titled âKey MethodologiesâThe recovery process utilized a combination of physical classification and chemical flotation, following an experimental design (Design of Experiments - DOE) to model reagent influence.
- Material Collection and Sampling: Fibro (fines from natural stone processing) was collected directly from the effluent treatment box of a granite processing plant (100% granite materials).
- Preparation and Homogenization: Over 500 kg of Fibro was collected, deposited in piles, and homogenized using standard mining demonstration methods.
- Granulometric Classification: Material was classified using a suspended vibrating penetrator (in accordance with NBR 7181/2:2018). The fraction between 28 mesh and 65 mesh was selected, corresponding to the typical diamond grain sizes used in rock cutting tools.
- Sample Preparation: Samples (400 g for Group 1, 500 g for Group 2) were dried, homogenized using a Jones type quartet, and prepared according to the 32 factorial experimental plan.
- Flotation Equipment: A bench flotation equipment (Engendrar model CFB 1000N) with a 2 L tank was used, featuring a motor, pulley, and rotor/stator for pulp agitation and air insertion.
- Reagent Testing: Two variables were tested at three levels (-1, 0, 1): Collector (Kerosene) and Foaming Agent (Methyl Isobutyl Carbinol - MIBC).
- Operational Conditions: Two groups of solid percentages were tested: Group 1 (35% solids conditioning, 25% flotation) and Group 2 (40% solids conditioning, 30% flotation).
- Data Analysis: Statistical analysis, including regression models and Response Surface Methodology (MSR), was applied using Statistica 10.1 software to determine optimal parameters.
6CCVD Solutions & Capabilities
Section titled â6CCVD Solutions & CapabilitiesâThe successful recovery of synthetic diamond micro-grains highlights the materialâs extreme durability and high economic value in industrial tooling. 6CCVD provides the foundational, high-specification MPCVD diamond materials necessary to manufacture the next generation of high-performance cutting and polishing tools, or to develop advanced sensing technologies for process control.
Applicable Materials for Tooling and Research Extension
Section titled âApplicable Materials for Tooling and Research Extensionâ| Application Focus | 6CCVD Material Recommendation | Key Capability Match |
|---|---|---|
| High-Performance Tooling | Polycrystalline Diamond (PCD) Wafers/Plates | Custom dimensions up to 125mm for large tool inserts. Superior thermal stability and toughness for sawing/polishing matrices. |
| Precision Wear Parts | Single Crystal Diamond (SCD) Plates | SCD offers unmatched hardness and purity for critical wear surfaces or micro-tooling components. Available in thicknesses 0.1”m - 500”m. |
| Electrochemical Sensing | Boron-Doped Diamond (BDD) Films/Wafers | BDD electrodes are ideal for monitoring reagent concentrations (collector/foaming agent) or analyzing mineral content in the Fibro waste stream, enabling real-time process optimization. |
| Optical/Thermal Management | Optical Grade SCD | For advanced tools requiring integrated thermal management or high-power laser processing (e.g., laser-assisted cutting). |
Customization Potential for Industrial Integration
Section titled âCustomization Potential for Industrial IntegrationâThe study confirms that synthetic diamond is typically integrated into metal matrices (sintered tools). 6CCVD offers specialized services to facilitate the integration of high-purity CVD diamond into new tool designs:
- Custom Dimensions: We provide PCD plates up to 125mm in diameter, allowing manufacturers to design larger, more efficient cutting segments than those using recovered micro-grains.
- Advanced Metalization: 6CCVD offers in-house metalization services (Au, Pt, Pd, Ti, W, Cu) crucial for creating robust, high-strength bonds between the diamond material and the metallic matrix used in sawing and polishing tools.
- Surface Finish: For high-precision polishing applications, 6CCVD guarantees ultra-low roughness (Ra < 1nm for SCD, Ra < 5nm for inch-size PCD), ensuring optimal performance and longevity of the finished tool.
Engineering Support
Section titled âEngineering SupportâThe successful flotation methodology relies on precise material characterization and understanding surface chemistry (hydrophobicity). 6CCVDâs in-house PhD team specializes in the physical and chemical properties of CVD diamond.
- Material Selection Consultation: We assist engineers in selecting the optimal SCD or PCD grade based on specific application requirements (e.g., impact resistance, thermal conductivity, or chemical inertness) for new rock cutting and polishing projects.
- Process Optimization: Our experts can provide guidance on integrating CVD diamond into complex manufacturing processes, including advising on metalization layers for optimal sintering or brazing into tool bodies.
- Global Logistics: 6CCVD ensures reliable global shipping (DDU default, DDP available) of high-value diamond materials, supporting international research and industrial supply chains.
For custom specifications or material consultation, visit 6ccvd.com or contact our engineering team directly.
View Original Abstract
Objective: The objective of this study is to investigate the flotation process of the fines from the processing of natural stones - Fibro, and to propose a methodology to recovery synthetic diamonds present in it. For this, this research analyzes the influence of the amount of solid mass in the pulp and the amount of reagents used in the process. Theoretical Framework: The productive chain of natural stones generates millions of tons of Fibro annually, which can cause environmental damage if not disposed of or treated properly. Considering that the principles of circular economy are relevant in the pursuit of sustainable development of the sector, it is emphasized that Fibro contains several mineral resources that can be used in other productive chains. In addition to the rock powders resulting from processing, there are other particles of interest such as synthetic diamond. The synthetic diamonds present in Fibro come from the diamond tools used in rock sawing and polishing. These diamond particles have a high added value, and some recovery methods have been implemented to capture these grains for reuse. Among the methods used for this purpose, flotation has obtained the best results in previous studies. Method: The methodology adopted for this research begins with the collection and sampling of the Fibro in the natural stone production industries. Then, this material was classified granulometrically through sieving, and the samples were then subjected to the flotation process. In flotation, the percentage of solids in the pulp and the amounts of collector and frother used in the process were tested. All untested parameters were kept constant, and only the variables under investigation were modified at different levels. The methodology followed an experimental design and it was applied regression models and response surfaces for data modeling. Results and Discussion: The results show that the most efficient solid percentage was 35% in conditioning and 25% in flotation. Regarding the quantities of reagents tested, the model generated by the response surface indicates which levels obtained the best results in terms of concentrate recovery rate. It was also noted that the amount of collector had little influence on the process, which can be inferred by the natural hydrophobicity of the diamond. Implications of the Research: The implications of this research include economic benefits for the natural stones industry from the possibility of entering a new market in the sector. As well as advances in circular economy by reusing industrial waste and developing new technologies for the use of these materials. These results have the potential to impact industrial sustainability and can expand the mining and metallurgy sector. Originality/Value: This study contributes to the mining industry by proposing an innovative flotation methodology to recover synthetic diamonds from the fines of processing of natural stones. The relevance and value of this research are evidenced by its ability to provide a practical and efficient solution, with potential positive impact on circular economy and industrial sustainability.