Reverse ADOR: reconstruction of UTL zeolite from layered IPC-1P

Abstract

The Assembly-Disassembly-Organisation-Reassembly (ADOR) process has led to the discovery of numerous zeolite structures, albeit limited to materials with decreased pore size in relation to the parent germanosilicate zeolite. This limitation...

Modified reverse ADOR assembles Al-rich UTL zeolite from IPC-1P layers

“…TBA cations increase the interlayer distance and produce an IPC-1TBA precursor with a d -spacing similar to that of the parent UTL zeolite (1.44 nm). 18 This intercalation requires a basic environment for the deprotonation of the silanol groups on IPC-1P and for the separation of its layers. However, IPC-1P layers gradually deteriorate under basic conditions, which promotes the formation of defects, mesopores, and eventually causes the dissolution of the layers, thus accounting for the poor yields of the intercalated material, IPC-1TBA.…”

“…The only exception to this rule is IPC-7 in which some D4R units are preserved during the treatment and the recently developed Reverse ADOR approach. 16,18…”

“…Furthermore, the intercalation and reconstruction treatments partially dissolved the precursor resulting in poor yields of final zeolites. 18…”

An Extra-Large Pore Zeolite Enabled by 1D-to-3D Topotactic Condensation

“…S3). The cations are occluded intact, as demonstrated by 13 C and 31 P NMR (Fig. S4) and amount to 8.85 OSDA/uc according to C analysis (25.0%).…”

“…For pure silica zeolites, this kind of unit is strained and up to now was believed to need a fluoride anion close to its centre to be accessible for crystallization 12 since it has never been seen before in a silica zeolite synthesized without the use of fluoride anions. Only the "reverse ADOR" process, a postsynthetic modification that breaks Ge-containing D4R to then restore them as silica D4R, can also possibly produce these units, although no conclusive proof of the complete silica restoration ( 29 Si MAS NMR, FTIR in the OH stretching region, structural refinement) has been provided so far 13 .…”