Evolution of the porosity and characterization of alumina matrix proppants from bauxite, ball clay and natural manganese ore

A series of alumina matrix proppants based on the composition of bauxite and ball clay were studied. In order to improve the sinterability and mechanical properties, natural manganese ore (NMO) was used as a doping additive. The phase formation was estimated by XRD, the crush strength under 52 MPa closing pressure was measured, and as well the densification process was evaluated by the apparent density, real density, pore size distribution and microstructure. The results show that NMO doping leads to achieving a good crush strength in a wide temperature range of 1150-1350 degrees C. Open porosity decreased significantly at a high temperature of 1350 degrees C by doping with NMO, whereas closed porosity increases because of the existence of a considerable Fe2O3 content and excessive grain growth. The proppant obtained with a high crush strength and low apparent density, prepared by doping with 5 wt.% NMO and sintering at 1350 degrees C is beneficial to its utilization in the petroleum or gas industries.