Synthesis of cationic organoclay and applications to environmental areas

Abstract

The concept of ‘self-assembly of organoclay nanotechnology’ is of significant importance for constructing hybrid nano-objects in equilibrium and non-equilibrium and the environment for practical applications, which have been extended to the nanotechnology due to the unique, remarkable physicochemical properties and multi-functions. The main objective of this research is to realize cationic organoclay nanotechnology by functionalized magnesium phyllosilicate (Mg clay) and its derivatives. We have developed organoclay nanotechnology based on positively charged organo-building blocks, i.e. self-assembly process to fabricate functional nanomaterials, to wrap anionic and heavy metal contaminants, and to selectively interact with microalgae e.g. red tid as an algicidal agent. In detail, high-density amine groups of Mg clay functioned as template sheathed materials of J-aggregate rod structure by self-assembly of TPPS (porphyrin monomers). Furthermore, the gallery of nanomaterials composed of organoclay and anionic contaminants was reassembled for water treatment. This novel application of cationic organoclay into environmental area opens a new window to treat for a variety of negatively charged toxic chemical from water. Furthermore, binding affinity of protonated exfoliated dispersion of Mg clay with cadmium and lead was applied with an inexpensive and environmental friendly soil flushing agent. In respect to microoalgae with this organoclay, ammonium property of cationic organoclay showed selectively algicidal activity, resulting in inhibition of algal bloom while little affecting other living microorganisms in sea water, which experiments were conducted batch, microcosm, and mesocosm. As synthesis of organoclay described herein was simple technology to prepare diverse functionalized side chains and various backbone metal ions such as $Mg^{2+}$, $Al^{3+}$, $Fe^{3+}$, $Cu^{2+} etc. in ambient condition via sol-gel reaction: hydrolysis and condensation. In particul...