Facile synthesis of the DD3R zeolite: performance in the adsorptive separation of buta-1,3-diene and but-2-ene isomers

Abstract

Small pore size and hydrophobic nature of DD3R make this material a unique zeolite with high potential in industrial separation applications. However, the reproducible rapid synthesis of this zeolite is still a problem. In this work, a thorough assessment of different synthetic methods revealed that synthesis reproducibility relies on two main pillars: the use of properly cleaned autoclave liners and the synthesis composition. High quality DD3R crystals are obtained when KOH is used as a cleaning agent, eliminating memory effects, and when KF is used in the synthesis as a mineralizing agent. H NMR reveals that template molecules accommodated within the cages are sticking to these 8-ring windows through their amine group. High quality DD3R crystals are applied in the adsorptive separation of buta-1,3-diene and but-2-ene isomers, one of the most energy intensive separations in chemical industry. Mixture separation experiments revealed that the 8-ring apertures of the DD3R cages are only accessible to trans-but-2-ene and buta-1,3-diene, while excluding but-1-ene and cis-but-2-ene molecules, resulting in shape-selective separation in the presence of C4 mixtures.

Multi-scale crystal engineering of metal organic frameworks

“…Solids with well-defined porosity, the so-called molecular sieves, allow the manipulation of molecules with an exquisite level of control. Today it is possible to separate molecules which differ in size even a few tenths of an Ångstrøm by using the adequate molecular sieve [3,4], and to confine catalytic reactions in pores of similar size as that of reactants and products allowing the selective production of commodity chemicals at affordable prizes and minimized waste [5]. Indeed, it would not be controversial to state that materials such as zeolites have, to a large extent, shaped our current lifestyle.…”

Sustainable Separations of C4‐Hydrocarbons by Using Microporous Materials

“…[13] This can give advantages in terms of product recovery andp urity,a s well as energy costs. [7,14,15] Herein, we look at the state of the art of C 4 separation by using microporous materials, with recommendations for possible industrial applications…”

Synthesis and characterization of all-silica DDR zeolite by microwave heating

“…The use of KF as mineralizing agent increased the solubility of silica, which enhanced the nucleation, thus led to shorter synthesis time and smaller crystals (~5 mm) [26]. Gucuyener et al found the proper cleaning of Teflon liner eliminates the memory effect (or the interference of other phase) and thus improves the reproducibility [27]. Yang et al prepared DDR with the aid of ballmilled Sigma-1 seeds, an aluminum-containing structural analog of DDR.…”