Abstract
Zircon is always found in association with Ti-rich minerals; therefore, it is produced mainly as a co-product in the production of ilmenite and rutile from placer mining operations. In Cox’s Bazar beach sands, they contain at 2.8, 12.1 and 2.7 wt% (average) respectively in the heavies. In order to scrutinize mineralogical and geochemical variability among Zr- and Ti- rich minerals, XRF, XRD, SEM and EPMA were implemented. Petrogenesis manifests the nature of impurities in mineral concentrates where they included through cationic substitution during alteration and metamictization, whereas their coating and pore filling occurred by hydraulic action in fluvial process. The impurities of oxides, silicates and phosphates gangue mineral phases degrade the quality of zircon concentrate (ZrO2 + HfO2 = 63.73 wt%) in achieving premium grade. Although the process of hot acid leaching (HAL) upgrades the quality enhancing ZrO2 + HfO2 (69.10 wt%) content, yet to be eliminated Fe and U to reach premium grade. Thermal annealing and calcining treatment is suggested to fully recover the zircon prior to industrial use. Similar to zircon, ilmenite and rutile they both contain trace levels of gangue mineral phases. The content of TiO2 and Ti/(Ti + Fe) (48.1 wt% and 0.5 respectively) indicates unaltered ilmenite. Therefore, upgrading the unaltered low grade ilmenite concentrate to chlorination feedstock, ilmenite smelting and the synthetic rutile routes are suggested. In addition, the TiO2 (83.84 wt%) content in the bulk rutile concentrate shows as much as the high grade ilmenite display due to contaminants. Mentioning, two of the major impurities such as tin and zirconium occurred as mineral grain cassiterite and zircon and as substitutions for titanium (Ti ⇌ Sn, Zr) in crystal lattice. The way of acid leaching can be instrumental not only for upgrading rutile but also for extracting Sn and Zr as byproduct of Ti metal/ TiO2 pigment.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
