@article{Lan_Duong_Anh_Man_2019, title={Research on fabrication of non-calcined geopolymer ceramics from kaolin Tung Ba, Vi Xuyen, Ha Giang}, volume={41}, url={https://vjs.ac.vn/index.php/jse/article/view/14371}, DOI={10.15625/0866-7187/41/4/14371}, abstractNote={<p>The mineral component of kaolin clay in Tung Ba commune analyzed by X-ray diffraction is composed mainly of kaolinite (24–27%), illite (26–30%) and quartz (40–44%). Chemical composition (wt%) of Tung Ba kaolin determined by X-ray fluorescence (XRF) shows SiO<sub>2</sub> at 59.92–64.98, Al<sub>2</sub>O<sub>3</sub>: 18.95–20.82, Fe<sub>2</sub>O<sub>3</sub>: 2.28–3.95, SO<sub>3</sub>: 2.47–4.66, CaO: 0.12–0.36, MgO: 1.72–2.13 and TiO<sub>2</sub> at 0.75–1,08. To fabricate geopolymer ceramic, kaolin clay was transformed into metakaolin with the optimal parameters of calcination: the temperature at 750°C and heating time of 120 min. Obtained metakaolin is mixed with mixtures of NaOH/Na<sub>2</sub>SiO<sub>3</sub> (40%wt) with ratios of 0.2, 0.25, 0.33, 0.5 and NaOH molarities are 10M, 12M, 14M. Testing geopolymer ceramics after 28 days had a compressive strength of 40–196 KG/cm<sup>2</sup>, water absorption of 15.25–17.98% and density of 1.54–1.69 g/cm<sup>3</sup>, totally satisfied the Vietnamese standard for construction bricks and ceramics.</p>}, number={4}, journal={Vietnam Journal of Earth Sciences}, author={Lan, Tran Thi and Duong, Nguyen Anh and Anh, Phan Luu and Man, Tran Thi}, year={2019}, month={Aug.}, pages={388–402} }