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Te atoms were loaded into nanochannels of zeolite AFI single crystals. The polarized absorption and Raman scattering spectra were measured. The absorption spectra of Te loaded AFI showed large anisotropic properties. The absorption spectra of E//c deeply depended on the loading density of Te atoms. In low Te loading density, Te was adsorbed into the nanochannels in a dimer form whose absorption peak appeared at ca. 3.5 eV. In high loading density, Te form one dimensional nanowires inside the channels. Nanowire formation causes large anisotropic absorption and changes in the spectral shape.

Calcined Na-ZSM-5 zeolite was directly reacted with the chloroauric acid solution in different concentrations and pH for gold loading process. The synthesized Au/ZSM-5 catalyst was then characterized using XRD, BET, SEM, TEM and EDS techniques. In order to evaluate its catalytic activity, effect of temperature on CO conversion was investigated.

Zeolites with unique framework structure have wide applications, such as ions’ exchangers, molecular sieves and catalysts. This work focused on the synthesis and characterization of zeolite by recycling coal fly ash as the starting material via hydrothermal method. The intermediate phases and final products were characterized by XRF, XRD, FT-IR, SEM and BET techniques. The effects of aging time on the crystallization/transformation of zeolite were discussed. The results showed that the alkali-activated coal fly ash after hydrothermal process could lead to the formation of zeolite Na-P1. Furthermore, the aging treatment benefited the formation of homogenous zeolite Na-P1 with smaller particle size, larger specific surface area, total pore volume and pore size.

Perovskite LaFeO₃/ZSM-5 is synthesized via citrate route for H₂S removal at high temperatures. It shows good thermal stability after heat treatment at 500–700^∘C with respect to slight changes in crystallographic phase and textural property. It presents the optimal desulfurization performance at 600^∘C with sulfur capacity of 1017$\mu$molS/g and products of S, LaS₂, and Fe₇S₈. Sulfidation at 500^∘C yields the same products as sulfidation at 600^∘C but displays the lowest sulfur capacity of 408$\mu$molS/g. Sulfidation at 700^∘C produces La₂O₂S, Fe₃S₄, and unreacted LaFeO₃. The activation energy of the sulfidation reaction over LaFeO₃/ZSM-5 is 109.6kJ/mol.

Here we present a systematical investigation on the effect of high-level layer selection in our own N-layered integrated molecular orbital + molecular mechanics (ONIOM) method. We used the adsorption of Na⁺ in the M7 site of ZSM-5 as an instructive example. We embedded n tetrahedral sites (nT= 7, 19, 22, 33) for high-level layer into a low-level layer represented by 75T (denoted as nT@75T). Our calculations showed that 7T@75T behaved poorly in both structure optimization and interaction energy calculation. Hence only including the first coordination circle of the ion (i.e. 7T), as commonly used in literature, is not sufficiently good. However, for n ≥ 19, both structure optimization and interaction energy calculation by ONIOM are in good agreement with the full 75T model calculation. Such a reliable ONIOM calculation needs only 1/10 to 1/5 computational time for each self-consistent field (SCF) iteration as compared to the full 75T model calculation, highlighting its pivotal role in zeolite simulation.

Thin-film zeolite-filled silicone/PVDF composite membranes were fabricated by incorporating zeolite particles into PDMS (poly(dimethylsiloxane)) membranes. The morphology of zeolite particles and zeolite filled silicone composite membranes were characterized by SEM. The zeolite-filled PDMS/PVDF composite membranes were applied for the pervaporation of ethanol/water mixtures and showed higher flux compared with that reported in literatures. The effect of zeolite loading and Si/Al ratio of zeolite particles on pervaporation performance of ethanol/water mixtures was investigated. With the increase of zeolite loading from 10% to 30%, the total flux increased significantly from 265.0 g/(m²h) to 820.7 g/(m²h) with 5 wt% ethanol feed concentration at 50°C, and the separation factor increased from 11.3 to 13.7. The effects of operation temperature and ethanol feed concentration on pervaporation performance were also studied. As the temperature increased from 40°C to 80°C, the separation factor varied from 12.1 to 13.7 which maintained the maximum value at 50°C, and the total flux increased exponentially from 435.5 g/(m²h) to 2993.8 g/(m²h) with 30% zeolite loading. Besides, the zeolite filled PDMS/PVDF composite membrane with 30% zeolite loading was ethanol perm-selective over a wide range of ethanol feed concentration (5 wt%–90 wt%), and especially showed excellent pervaporation performance in the low concentration range.

In recent years, considerable interest has increased on the use of chemical and biomedical sensor arrays in conjunction with pattern recognition analysis for the identification of gases, liquid system or the determination of antigen-antibody interaction. Some sensor arrays technologies based on work carried out at Fudan University (China) are presented including (1) microcantilevers in resonating mode (2) polymer-based sensor arrays (3) capacitive immunosensor arrays.

ZSM-5 zeolites were hydrothermally synthesized in three different seeding pathways under the direction of tetrapropylammonium bromide (TPABr) template. In order to investigate the seeding effect in ZSM-5 crystallization process, ZSM-5 crystals and pre-fabricated MFI-type nanoseeds were added into the original self-induction system, respectively. The final ZSM-5 zeolites were systematically investigated based on XRD (X-ray diffraction), SEM (scanning electron micrograph), TEM (transmission electron micrograph), nitrogen adsorption characterizations and NH₃-TPD (ammonia-temperature programmed desorption). The self-induction system produced ca. 20 μm ZSM-5 zeolite displaying hexagonally uniform prisms. After the addition of ZSM-5 crystal seeds, the crystal sizes were decreased greatly to ca. 5 μm. When MFI-type nanoseeds were adopted, irregular aggregate particles consisting of 20–50 nm primary particles were rapidly synthesized. The varied hydrothermal crystallization kinetics of the three synthesis system was also explored. Adjusting the seed agents alone, ZSM-5 crystals with diverse structural, morphological, textural and hydrothermal behaviors could be fabricated conveniently. The three ZSM-5 zeolites loaded by 0.05 wt.% Pt were assessed for the xylene isomerization reaction to investigate the particle size effect on the catalytic properties.

Sulfated TiO₂ nanoparticles were successfully immobilized on zeolite through improving hydrolysis-deposition method. Microstructure, crystallization, surface state and surface area of composite catalysts were characterized by SEM, XRD, FTIR spectra, XPS and BET and the photocatalytic activity was evaluated by degradation of methyl orange under UV irradiation. We optimized these factors (SO${}_4^{2-}$ ions, calcination temperature and loading amount of sulfated TiO${}_2)$ on photocatalytic activity and crystallization of composite photocatalysts. The results indicated that the SO${}_4^{2-}$ ions are successfully immobilized on the surface of TiO₂, and sulfated TiO₂/zeolite show the highest photocatalytic activity for methyl orange at the [SO${}_4^{2-}$]/[Ti${}^{4+}$] molar rate of 1:1, calcination temperature of 600${}^{\circ }$C for 2h, and sulfated TiO₂ loading amount of 40%, respectively.

For the radio frequency-based catalyst state monitoring of SCR catalysts, the dielectric properties of the used SCR catalyst materials are essential to design the measurement system and to adjust it to the given conditions. This work focuses on the experimental determination of the effective complex dielectric properties of zeolite coatings on cordierite substrates and the approximation of the latter to describe and transfer these systems in an easier manner. Therefore, different influences were investigated to approximate the real and the imaginary part of the complex permittivity of zeolite coatings on cordierite substrates.

Today, fossil carbon provides us with fuels (energy), polymers (packaging, insulating and building materials, household utensils, glues, coatings, textiles, 3D-printing inks, furnitures, vehicle parts, toys, electronic and medical devices, etc.) and biologically active substances (drugs (Chapter 9), flavorings, fragrances, food additives, plant protection products, etc.). In this chapter we discover the modern materials of our civilization which are very often polymers derived from oil. They are referred to as “plastics” (annual world production: 380 × 10⁶ tons). Their production consumes 8% of the crude oil extracted (ca. 5 billion tons per year). An increasing part of the plastics originates from renewable resources (less than 10% today, see Section 11.10, bio-sourced plastics). Plastics make life easy for us, but at the underestimated cost of damage to our environment (Figure 8.1) and our health. They contaminate the hydrosphere and the agricultural soil. The atmosphere is also contaminated by microplastics…

Modern humans are heavily dependent on chemicals and have constantly looked for improved molecular designs with better efficiency and simple ways to get them. This is why catalysis, the method of getting upgraded chemicals through modern processes using a suitable catalyst, is an important area of research. At least one catalytic step is involved in 90% of the manufacturing of chemical products nowadays. Since chemical processes are always associated with a potential environmental hazard, the behavior of the catalyst used is of specific significance concerning environmental resistance. Therefore, the used catalysts should be explored for complete restoration even in the case of 100% efficiency. Zeolites are a group of materials with the characteristics of thermal and chemical stability and can be regenerated by calcination. Because of these crucial features, these types of materials have been widely used in various catalytic reactions and large-scale petrochemical procedures. The gas-phase reactions in zeolite have been intensively studied to develop zeolite as acid–base and redox catalysts to generate fine chemicals. Furthermore, the encapsulation of different metal complexes within the zeolite pores makes them attractive catalytic materials to contribute as a potential component for various industrial organic transformation processes.

The potential applications for heterogeneous catalysts (supported metallic complexes, metal–organic frameworks (MOFs) or polynuclear complexes) in C–H and C–OH activation are tantalizing. In response to the opportunity, novel strategies have been recently developed, which present a critical step toward harnessing the experimental factors, such as yield and selectivity, by enabling new techniques and hence real-world applications. This chapter provides an up-to-date survey (from the past five years) of the most promising novel routes by summarizing the progress made in the use of unconventional activation methods for performing oxidation reactions, highlighting the synergy of these technologies with heterogeneous catalysis. Focus is centered on both usual catalysts activation methods and less usual ones, such as ultrasounds, microwaves, grinding (mechanochemistry), as well as their combined use.

The adsorption behavior of acetic acid on zeolite 13X was studied at 25°C, 35°C and 45°C in a batch experiment. Experimental data were applied to pseudo-first-order and pseudo-second-order adsorption kinetic models, and tested against Langmuir and Freundlich isotherms. Thermodynamic parameters (ΔG, ΔH and ΔS) of adsorption were also calculated. The data fit the pseudo-second-order kinetic model and Freundlich isotherm well. The calculated values of ΔG, ΔH and ΔS indicate that the adsorption is spontaneous and endothermic; it causes an increased extent of randomness at the solid-solution interface.