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Updated: Jun 21, 2026
05:41
Rapid Mix Preparation of Bioinspired Nanoscale Hydroxyapatite for Biomedical Applications
Published on: February 23, 2017
Ion adsorption behaviour of hydroxyapatite with different crystallinities
C Stötzel1, F A Müller, F Reinert
1Department for Functional Materials in Medicine and Dentistry, University of Würzburg, Pleicherwall 2, D-97070 Würzburg, Germany.
Colloids and Surfaces. B, Biointerfaces
|July 31, 2009
Summary
Hydroxyapatite (HA) with low crystallinity and high surface area effectively removes heavy metal ions. Higher crystallinity HA shows reduced ion adsorption capacity, forming pyromorphite and hopeite phases upon lead and zinc adsorption.
Area of Science:
- Materials Science
- Environmental Science
- Chemistry
Background:
- Hydroxyapatite (HA) is a key material in various applications, including environmental remediation.
- Understanding the relationship between HA's physical properties and its ion adsorption behavior is crucial for optimizing its use.
Purpose of the Study:
- To investigate the correlation between the crystallinity of hydroxyapatite (HA) and its ion adsorption capabilities.
- To evaluate the efficiency of HA with varying crystallinities and specific surface areas (SSA) in removing diverse ions from aqueous solutions.
Main Methods:
- Preparation of HA powders with controlled crystallinities (X(c)) and SSAs via precipitation and heat treatment.
- Adsorption experiments using multi-component ion solutions and single-element solutions (Pb, Zn) up to 250 ppm.
- Analysis of ion removal efficiency, adsorption isotherms, and post-adsorption material characterization using X-ray Diffraction (XRD).
Main Results:
- As-prepared HA (X(c)=0%, SSA=170 m²/g) quantitatively removed a wide range of divalent ions (Pb, Zn, Be, U, Bi, V, Al, Cu, Ga).
- Calcined HA (X(c)=65-95%, SSA=5-30 m²/g) showed quantitative removal for fewer elements (Pb, Bi, Ga).
- Rapid quantitative removal of Pb²⁺ and Zn²⁺ by as-prepared HA was observed within 10 minutes, forming pyromorphite and hopeite phases.
Conclusions:
- HA crystallinity significantly impacts its ion adsorption behavior, with low crystallinity and high SSA being optimal for broad-spectrum heavy metal removal.
- The formation of stable mineral phases like pyromorphite and hopeite indicates effective lead and zinc sequestration by HA.
- This study highlights the potential of tailored hydroxyapatite materials for efficient wastewater treatment and heavy metal remediation.
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