TY - JOUR
T1 - Mining tailings as raw materials for reaction-sintered aluminosilicate ceramics
T2 - Effect of mineralogical composition on microstructure and properties
AU - Karhu, Marjaana
AU - Lagerbom, Juha
AU - Solismaa, Soili
AU - Honkanen, Mari
AU - Ismailov, Arnold
AU - Räisänen, Marja Liisa
AU - Huttunen-Saarivirta, Elina
AU - Levänen, Erkki
AU - Kivikytö-Reponen, Päivi
PY - 2019/3/1
Y1 - 2019/3/1
N2 - This paper presents studies on the utilization of aluminosilicate-based mining tailings as raw materials for mullite-based ceramics. Based on the 3:2 stoichiometric composition, mullite was synthesised by reactive sintering with a series of powder mixtures with alumina additions. X-ray diffractometry and scanning electron microscopy analyses revealed that, at the specific mineralogical composition, mullite structure formed surrounded by an amorphous glass phase in reaction-sintered powder mixtures. Results demonstrated that the chemical and mineralogical composition of mining tailings do have an effect on mullite formation possibilities and, only with the particular mineralogical composition, the mullite formation is possible regardless of the correct Al:Si ratio in tailings. Physical and mechanical properties of the formed ceramics were defined, showing comparable values to 3:2 mullite reference. Mullite structure formation enables a better thermal resistance up to above 1450 °C of the formed tailings-based ceramics compared to other aluminosilicates, reflecting their utilization potential for refractory ceramic applications.
AB - This paper presents studies on the utilization of aluminosilicate-based mining tailings as raw materials for mullite-based ceramics. Based on the 3:2 stoichiometric composition, mullite was synthesised by reactive sintering with a series of powder mixtures with alumina additions. X-ray diffractometry and scanning electron microscopy analyses revealed that, at the specific mineralogical composition, mullite structure formed surrounded by an amorphous glass phase in reaction-sintered powder mixtures. Results demonstrated that the chemical and mineralogical composition of mining tailings do have an effect on mullite formation possibilities and, only with the particular mineralogical composition, the mullite formation is possible regardless of the correct Al:Si ratio in tailings. Physical and mechanical properties of the formed ceramics were defined, showing comparable values to 3:2 mullite reference. Mullite structure formation enables a better thermal resistance up to above 1450 °C of the formed tailings-based ceramics compared to other aluminosilicates, reflecting their utilization potential for refractory ceramic applications.
KW - Mining tailings
KW - Mullite
KW - Reaction sintering
KW - Refractory ceramics
KW - Utilization
UR - http://www.scopus.com/inward/record.url?scp=85057276435&partnerID=8YFLogxK
U2 - 10.1016/j.ceramint.2018.11.180
DO - 10.1016/j.ceramint.2018.11.180
M3 - Article
AN - SCOPUS:85057276435
VL - 45
SP - 4840
EP - 4848
JO - Ceramics International
JF - Ceramics International
SN - 0272-8842
IS - 4
ER -