Ultrafast and continuous synthesis of an aluminophosphate type zeolite in microchannel and the hydrogenation of α-pinene

Abstract

A highly efficient method was proposed for fast and continuous synthesis of LTA-type aluminophosphate (AlPO4-LTA) molecular sieves. The precursor was first synthesized in batch methods, then the precursor and tetramethyllamine hydroxide were coordinated to direct the synthesis of molecular sieves in a reaction system containing a poly (tetrafluoroethylene) (PTFE) microchannel reactor, which reduced the energy costs associated with mixing and cooling of reactant solutions. The reaction conditions, including molar ratio of reagents, temperature and flow rate, have also been rapidly optimized. The AlPO4-LTA have high crystallinity, high thermal stability, granule size (ca. 150 nm) and large surface area (679 m2/g). In addition, the hydrogenation of α-pinene catalyzed by Ni/AlPO4 nanocomposites was achieved with α-pinene conversion rate of 95.1% and cis-pinane selectivity of 95.9%, the catalyst had high activity during five cycles.

Keywords

• Continuous synthesis
• Aluminophosphate molecular sieve
• Microchannel
• Hydrogenation
• α-pinene