@article{ADAMS_Essien_Aiyeloro_Oseyomon_Makanjuola_2021, place={Bangkok, Thailand}, title={Facile purification of locally mined gypsum and its use for preparing nano-hemihydrates}, volume={31}, url={https://jmmm.material.chula.ac.th/index.php/jmmm/article/view/1119}, DOI={10.55713/jmmm.v31i3.1119}, abstractNote={<p><span style="font-weight: 400;">Gypsum has a wide range of applications, in interior decorations, building construction, supplements or implants in orthopaedics to mention a few. However, in many developing countries including Nigeria, there is still a large-scale importation despite huge available natural deposits. In this study, a facile method to purify locally-mined gypsum has been explored based on the mineral retrograde solubility in water. The purified gypsum was investigated for its elemental composition in comparison to the crude sample and a commercially obtained medical-grade gypsum using X-ray fluorescence (XRF). The results showed that the purified gypsum contained 94.05% CaSO</span><span style="font-weight: 400;">4</span><span style="font-weight: 400;"> compared with the crude which had a CaSO</span><span style="font-weight: 400;">4</span><span style="font-weight: 400;"> content of 58.10%. Hemihydrates obtained by the treatments of the purified gypsum in an oven, autoclave and microwave gave different morphologies when observed under a scanning electron microscope (SEM). Transmission electron microscopy (TEM) showed that particle sizes of all the hemihydrates were within the range 9 nm to 32 nm, but the microwave-derived sample exhibited the most desirable morphological characteristics which could impart high mechanical performance. We have reported here a new facile method for purifying gypsum ore that can have huge commercial benefits.</span></p>}, number={3}, journal={Journal of Metals, Materials and Minerals}, author={ADAMS, Luqman Ayodeji and Essien, Enobong and Aiyeloro, Taiwo and Oseyomon, Stella and Makanjuola, John}, year={2021}, month={Sep.}, pages={106–110} }