Statistical design for recycling kaolin processing waste in the manufacturing of mullite-based ceramics

Abstract

Mineral extraction and processing industries have been cited as sources of environmental contamination and pollution. However, waste recycling represents an alternative recovery option, which is interesting from an environmental and economic standpoint. In this work, recycling of kaolin processing waste in the manufacture of mullite-based ceramics was investigated based on the statistical design of mixture experiments methodology. Ten formulations using kaolin processing waste, alumina and ball clay were used in the experiment design. Test specimens were fired and characterized to determine their water absorption and modulus of rupture. Regression models were calculated, relating the properties with the composition. The significance and validity of the models were confirmed through statistical analysis and verification experiments. The regression models were used to analyze the influence of waste content on the properties of the fired bodies. The results indicated that the statistical design of mixture experiments methodology can be successfully used to optimize formulations containing large amount of wastes.

Experimental statistic design applied for obtaining Zn:xCe by microwave-assisted hydrothermal method with photocatalytic property

“…These values are shown in Table 6. From the table, we can see that with the dopant, there is a reduction in the energy band gap, because the impurity or dopant causes irregularity in the crystal lattice, affecting energy levels and providing new current carriers [15]. The ZnO doped with Ce shifts the absorption edge to the visible range and reduces the range of the band gap.…”

“…The design of experiments (DOE) approach can be used. Within the scope of DOE, factorial design and response surface methodology are important tools to determine the effects of process parameters and their interactions, as well as to optimize the process conditions [15][16][17][18][19].…”

The Kaolin Residue and Its Use for Production of Mullite Bodies

“…Studies conducted by our research group (Menezes et al, 2009a(Menezes et al, , 2009bBrasileiro et al 2006Brasileiro et al , 2008Santana et al, 2007) aimed at recycling the waste from the processing of kaolin, showed that the kaolin residue has high levels of SiO 2 and Al 2 O 3 , especially as a material of great potential for obtaining bodies that have properties for use in advanced ceramics, can be incorporated in ceramic formulations to obtain mullite.…”

Low-valued raw materials challenge the common eligibility criteria for triaxial ceramics

“…Thus, the ceramic industry, particularly the sector dealing with construction materials, can be regarded as a potentially high consumer of wastes from other industrial sources. This also brought to light the need to re-evaluate the large quantities of minerals formerly rejected due to incomplete fulfilment of standard requirements [7][8][9][10][11].…”