Synthesis of SAPO‐34 Zeolite from Laponite and Its Application in the MTO Reaction

Abstract

In this work, SAPO‐34 zeolite with high catalytic activity was successfully synthesized by hydrothermal method from laponite as the single Si source. Compared with the traditional method of synthesizing zeolites from clay, the laponite after swelling can be directly used in the synthesis process of zeolite. The crystallization behavior of SAPO‐34 synthesized from laponite was investigated by XRD, FTIR, N2 adsorption–desorption, SEM‐EDX, ICP‐MS, and DR‐UV/Vis. The process can be summarized as follows: the Si and Mg elements were produced by the depolymerization of laponite, then the primary building units of SAPO‐34 zeolite were formed under hydrothermal conditions; finally, the crystal nucleus began to form, and crystallization was triggered. Compared with the conventional SAPO‐34 synthesized from TEOS, the SAPO‐34 synthesized from laponite exhibited higher selectivity to light olefins and longer lifetime, which can be attributed to the suitable strength of acidity. This work points to a straightforward route to the synthesis of SAPO‐34 from laponite.

Facile Synthesis of an Mg‐incorporated ZSM‐5 Zeolite from Dual Silicon Sources and Its Application for Conversion of Methanol to Olefins

“…Based on the above results, the crystallization mechanism of ZSM‐5 zeolite synthesized from dual silicon sources could be briefly divided into three phases. Firstly, laponite was depolymerized by the attraction of TPA + and OH −1 under hydrothermal synthesis conditions [36,37] . Meanwhile, TEOS can be rapidly hydrolyzed into silicate species and thus provide nutrition for crystallization reaction.…”

“…Firstly, laponite was depolymerized by the attraction of TPA + and OH À 1 under hydrothermal synthesis conditions. [36,37] Meanwhile, TEOS can be rapidly hydrolyzed into silicate species and thus provide nutrition for crystallization reaction. Then, the depolymerized laponite containing highly reactive Si and Mg species could be converted in situ into zeolitic precursors and acted as crystalline seeds during the crystallization process, which is beneficial to form a large amount of nuclei in the synthesis system and thus the Mg species are incorporated in situ into the zeolite framework.…”

Lifetime‐Based Responsive Probes: Design and Applications in Biological Analysis

“…The pH of the microenvironment in the human body is usually maintained within a certain range. [33] Abnormal changes in the pH value of biological environments are usually closely related to the occurrence and development of diseases. [34] The gastric juice in the human body is generally acidic, which is conducive to the sterilization and digestion of food, but excessive acidity can cause damage to the gastric mucosa.…”

Synthesis and Applications of SAPO‐34 Molecular Sieves

“…The methanol to olefins (MTO) process has received considerable interest due to its importance in transforming abundant resources such as coal, natural gas, and biomass to widely demanded light olefins [1] . MTO is a crucial new C 1 chemical process, which refers to the chemical technology of producing low‐carbon olefins with methanol synthesized from coal or natural gas as raw material by the fluidized‐bed reaction.…”

“…[6] The SAPO-34 molecular sieves' narrow eight-ring windows limit its inherent diffusion bottleneck, leading to increased carbon deposition and rapid deactivation. Equation (1), below, shows that the relationship between catalyst activity and coke content is nonlinear. [7] ; ¼…”