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Ananion-dopedaluminiumchlorofluoride AlCl0.1F2.8(OTeF5)0.1(ACF-teflate) was synthesized.The material contains pentafluor-oorthotellurate(teflate)groups, which mimic fluoride ions electronically, but are sterically more demanding. They are embedded into the amorphous structure. The latter was studied by PDF analysis, EXAFS data and MAS NMR spectroscopy. The mesoporous powder is a Lewis superacid, and ATR-IR spectra of adsorbed CD3CN reveal a blue-shift of the adsorption band by73 cm-1, which is larger than the shift for SbF5. Remarkably,ACF-teflate catalyzes dehydrofluorination reactions of mono-fluoroalkanes to yield olefins in C6D6. In these cases,no Friedel-Crafts products were formed.
This paper is a case study of complete substitution of sodium-metasilicate in zeolite Na-A synthesis by an electrostatic filterash (FA) arising in high amounts during silane waste incineration process.The silicate abundant FA is a suitable material for reinsertion in zeolite chemistry. This is shown in the presented investigation by the development of a model reaction process at low temperatures (50–60 °C) and short times (1.5–4 h). The experiments were performed under addition of NaAlO2 and variation of the alkalinity and the reaction period. Characterization and fine tuning of the process was mainly done by studying the kinetics of FA digestion and zeolite crystallization by XRD and chemical analyses (ICP-OES) of solutions and solids. It could be shown that pure FA was mostly dissolved (98%) in 8 m NaOH already after 1 h. Addition of NaAlO2 and crystallization for further 60 min under optimized conditions at 50 °C yielded to a suitable product. It consists of zeolite Na-A (92% by mass) beside some hydrosodalite (8% by mass). According to this low temperature short time process this study is a contribution for the development of energy efficient recycling solutions.