Notice of RetractionResearch on preparation and characterization of an inorganic ion-exchange material

Notice of Retraction

After careful and considered review of the content of this paper by a duly constituted expert committee, this paper has been found to be in violation of IEEE´s Publication Principles.

We hereby retract the content of this paper. Reasonable effort should be made to remove all past references to this paper.

The presenting author of this paper has the option to appeal this decision by contacting TPII@ieee.org.

In this research, kaolin is used as the raw material and modified to prepare an inorganic ion-exchange material through different modification methods. In this paper, several surface feature evaluation methods (SEM, NMR, IR) are used to discuss and analyze the modification process of kaolin. According to CEC measurement, the obtained inorganic ion exchange material has an ammonium ion exchange capacity greater than 76.31mgNH₄⁺-N/g. SEM graphs provide the most direct view of the changes in the exterior topography due to the changes in the internal structure of the samples after the modification of kaolin. The ²⁷Al NMR indicates that ²⁷Al is mainly converted from hexa-coordinated Al to tetra-coordinated Al during the modification. Compared with that of the original kaolin, the ²⁹Si in the modified kaolin does not have any significant change in the average chemical environment except that a small part of the laminated and dendritic silicon-oxygen tetrahedrons are turned into inter-chain silicon-oxygen tetrahedrons.