Abstract

When unsintered hydroxyapatite (HA) is dissolved in acidic solution (pH less than 3), the calcium salt dissolves readily and may be re-precipitated at neutral pH values by neutralization with base. Maturation of this precipitate eventually leads to the neo-formation of calcium phosphates similar to HA. HA is a stable solid under neutral or basic conditions and has interesting adsorption properties. Particularly, textile dyes can be adsorbed on HA particles. Thermal treatment below 800°C degrades adsorbed organic matter and generates mineral HA. Such HA can be recovered and reused by re-dissolution in acidic water. We have experimented with such recycled HA the co-precipitation of textile dyes and found that HA can be reused several times. For most textile dyes, a very high level of color removal was observed (above 98%), with a small loss of HA during the recycling process (12%). This makes the treatment of textile dye polluted waters by HA co-precipitation feasible and sustainable.

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 call

Disclaimer: 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.