Microwave Effect on Clay Pillaring

Microwave-Assisted Pillaring of a Montmorillonite with Al-Polycations in Concentrated Media

“…Microwave-hydrothermal treatment has been widely used in recent years in materials science, making the preparation reactions faster than using traditional methods. In clay science, microwave-assisted methods have been used for the preparation of clay minerals, mainly saponite [ 10 ], and of Layered Double Hydroxides (LDH) [ 11 ], and also for the preparation of PILC [ 6 , 12 ].…”

Synthesis and application of pillared clay heterogeneous catalysts for wastewater treatment: a review

“…As reported by numerous studies water consumption can be significantly reduced by using concentrated clay suspensions and dry clay. 14,37,43 It has been reported that starting with dry clay generated the highest degree of modification. This could be attributed to strong interaction of vibrating molecules due to microwave radiation and generation of higher resistance in the medium, which also results in higher dielectric heating than in a diluted system.…”

“… 13 This method involves long periods of time and large amount of water, and such requirements represent a considerable shortcoming when trying to scale-up the pillaring method to industrial scale. 14 Therefore, the use of PILCs as heterogeneous solids catalysts has not been escalated to commercial levels, due to the fact that it has been challenging to perform the conventional laboratory synthesis method at industrial scale. 15 In order to reduce the large volume of water required, currently the pillaring method is focused on application of concentrated clay suspension, dry clay and concentrated pillaring agent solution.…”

The Synthesis of Organoclays Based on Clay Minerals with Different Structural Expansion Capacities

“…All minerals of the montmorillonite group have a low charge (0.2-0.6 units per elementary cell) due to a low degree of isomorphous ion replacement in the tetrahedral or octahedral sites, resulting in a weak electrostatic interaction between layers. The outer specific surface of smectite clays is as much as 40-70 m 2 /g, the total specific surface is 450-850 m 2 /g [50,51], and the porosity is about 0.006-0.010 cm 3 /g [52]. The cation exchange capacity determined by the traditional methods for smectites from different deposits is 65-135 cmol equiv/kg [53].…”