Hydrothermal Synthesis and Growth of Zeolites - Hydrothermal Technology - page 272

where R is an amine or quaternary ammonium ion. This organic species seems
to exert a unique structure-directing influence during the crystallization of zeolites.
Actually, when the first atlas of zeolite structure types was published in 1970,
some 27 zeolite structure types were reported [16] . During 1978, the structure com-
mission of International Zeolite Association (IZA) published about 38 entries in the
Atlas of Zeolite Structure Types by Meier and Olson [17] . Later, in 1987, the sec-
ond edition of the Atlas, comprising 64 structure types, was published [18] . The
third edition of the Atlas in 1992, compiled by Meier and Olson [19] , covers up to
1991 and carries about 85 entries of zeolite structure types. The Atlas has become a
frequently quoted work of reference and such a publication has to be frequently
updated. The current sixth edition of the Atlas published in 2007 has come out with
many more new entries of zeolite structure types, and a further new feature of this
edition is that characteristic building units are listed for each of the framework
types [20] . The list is expanding, and since the publication of the sixth revised
edition, several more entries have been added by the Zeolites Structure
Commission http://www.iza-structure.org/data-bases/ .
There are several zeolites' structure types reported from phosphates, and they
apparently constitute two distinctive categories of microporous materials. The
microporous zeolite-type materials are listed in Table 6.3 .
The primary building block of the zeolite structure is a tetrahedron of four oxy-
gen atoms surrounding a central Si atom (SiO 4 ). These are connected through their
corners of shared oxygen atoms to form a wide range of small secondary building
units (SBUs). They are interconnected to form a wide range of polyhedra, which in

Table 6.3 Microporous Zeolite-Type Materials a

ABW ACO AEI AEL AEN AET AFG AFI AFN AFO AFR AFS
AFT AFX AFY AHT ANA APC APD AST ASV ATN ATO ATS
ATT ATV AWO AWW BCT BEA BEC BIK BOF BOG BPH BRE
BSV CAN CAS CDO CFI CGF CGS CHA -CHI -CLO CON CZP
DAC DDR DFO DFT DOH DON EAB EDI EMT EON EPI ERI
ESV ETR EUO EZT FAR FAU FER FRA GIS GIU GME GON
GOO HEU IFR IHW IMF IRR ISV ITE ITH ITR -ITV ITW
IWR IWS IWV IWW JBW JRY JST KFI LAU LEV LIO -LIT
LOS LOV LTA LTF LTJ LTL LTN MAR MAZ MEI MEL MEP
MER MFI MFS MON MOR MOZ MRE MSE MSO MTF MTN MTT
MTW MVY MWW NAB NAT NES NON NPO NPT NSI OBW OFF

OSI OSO OWE -PAR PAU PHI PON PUN RHO -RON RRO RSN

RTE RTH RUT RWR RWY SAF SAO SAS SAT SAV SBE SBN

SBS SBT SFE SFF SFG SFH SFN SFO SFS SFV SGT SIV

SOD SOF SOS SSF SSY STF STI STO STT STW -SVR SZR

TER THO TOL TON TSC TUN UEI UFI UOS UOZ USI UTL

UWY VET VFI VNI VSV WEI -WEN YUG ZON

a Database of zeolite structures, by Structure Commission of the International Zeolite Association (IZA-SC) 2012.