Aluminium copper pillared clay membrane: application for dyestuff filtration

Abstract

Membrane production from Al-Cu pillared clay has been carried out. Al-Cu pillared clay was made by mixing Al-Cu pillared solution in clay suspension with Al3+ and Cu2+ molar ratio of 8: 2 while molar ratio of [OH−]/[Cu2++ Al3+] was 2.2. The clay suspension was dried at 60°C for 5 hours to remove water molecules in the clay structure and then calcined for 4 hours at 200°C, 300°C and 400°C with a heating rate of 1°C/minute. The pillared clay obtained was then characterized by XRD and GSA. Further, the pillared clay was moulded into a membrane to further test its performance for dye filtration. The X-Ray Diffraction (XRD) results showed that the natural clay had a basal spacing (d001) of 15.08 Å. While, the pillared clay had dooi of 17.34 Å, 16.05 Å, 16.37 Å and 15.62 Å for the heating temperature of 60°C, 200°C, 300°C and 400°C respectively. The diameter of the Al-Cu pillared clay (38 Å) was greater than that of the natural clay (34 Å). Meanwhile, the membrane surface area was 50.48 m2/g, which was almost the same with natural clay (52.45 m2/g). The methylene blue filtration process displayed the clear-colour filtration results in all concentrations. Meanwhile, the measurements using the UV-Vis spectrophotometer produced a colour rejection of up to 99.92% and this increased as the methylene blue concentration was augmented. Whilst, the water flux was up to 3.51 × 10−6 kg min−1 m−2 Pa−1 and decreased with the increasing of concentration.