LIU Xuguang, CHEN Shengbo, ZHANG Baoquan. Influence of temperature ramp rate and crystallization mode on synthesis of SAPO-5 via solid-phase transformation[J]. CIESC Journal, 2013, (2): 735-741.
LIU Xuguang, CHEN Shengbo, ZHANG Baoquan. Influence of temperature ramp rate and crystallization mode on synthesis of SAPO-5 via solid-phase transformation[J]. CIESC Journal, 2013, (2): 735-741.DOI: 10.3969/j.issn.0438-1157.2013.02.045.
Solid-phase transformation is a favorable method for preparation of Si substituted aluminophosphate molecular sieves (SAPO-5).The influence of temperature ramp rate and crystallization mode on the structure of SAPO-5 crystals was investigated by using XRD
SEM and EDS.Pure SAPO-5 phase could be synthesized with high (140℃·h-1) and low (5.8℃·h-1) temperature ramp rates.But SAPO-5 as well as SAPO-34 would be obtained with medium temperature ramp rates (17.5—70℃·h-1).Crystallization mode affected obviously the morphology of SAPO-5.With medium temperature ramp rates
sphere-shaped and hexagonal plate-like SAPO-5 crystals were prepared under dynamic and static crystallization modes respectively.But the substitution mechanism of Si might be SM3 under both crystallization modes.However
crystallization mode did not influence the morphology of SAPO-5 prepared at high and low temperature ramp rates.Substitution mechanism of Si might be SM2 and SM3 under dynamic and static crystallization mode respectively.