The influence of swelling (i.e. the size of tetraalkylammonium surfactant molecule, the presence of tetrapropylammonium hydroxide (TPAOH), pH) and pillaring (i.e. the ratio between the swollen precursor IPC-1P and tetraethyl orthosilicate) conditions on the structure and textural properties of the resulting materials was studied in detail for IPC-1P, which is the layered precursor of zeolite PCR. The swelling of IPC-1P proceeds efficiently under basic conditions both in mixed C(n)H(2n+1)N(CH3)3Cl/TPAOH systems and in C(n)H(2n+1)N(CH3)3OH (n = 8, 10, 12, 14, 16, 18) solutions at pH = 13-14. The intercalation of C(n)H(2n+1)N(+)(CH3)3 in IPC-1P resulted in the formation of expanded materials with interlayer distances growing with increasing length of the alkyl chain in C(n)H(2n+1)N(CH3)3(+): 1.59-1.86 (n = 8) < 1.89-2.11 (10) < 2.05-2.26 (12) = 2.08-2.26 (14) < 2.37-2.43 (16) < 2.57-2.71 (18) Å. IPC-2 zeolite was formed during calcination of IPC-1P samples swollen in C(n)H(2n+1)N(CH3)3OH solution, while PCR zeolite can be obtained by calcination of IPC-1P treated with either C(n)H(2n+1)N(CH3)3Cl/TPAOH or C(n)H(2n+1)N(CH3)3Cl. The pillaring of IPC-1P samples swollen with C(n)H(2n+1)N(CH3)3OH provided mesoporous materials with narrow pore size distribution in the range 2.5-3.5 nm. Pillared materials derived from the samples swollen in the presence of TPAOH were characterized by a broader pore size distribution. The optimal TEOS/IPC-1PSW ratio being sufficient for the formation of well-ordered pillared derivatives characterized by improved textural properties (S(BET) = 878 m(2) g(-1), V(total) = 0.599 cm(3) g(-1)) was found to be 1 : 1.5.

J Heyrovský Institute of Physical Chemistry Academy of Sciences of the Czech Republic v v i Dolejškova 3 CZ 182 23 Prague 8 Czech Republic

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