Effect of Modified Silica Materials on Polyvinyl Chloride (PVC) Substrates to Obtain Transparent and Hydrophobic Hybrid Coatings

In this research, we report a simple and inexpensive way to prepare transparent and hydrophobic hybrid coatings through deposition of different silica materials on polyvinyl chloride (PVC) substrates. The silica materials were prepared using an acid-catalyzed sol–gel method at room temperature (25 ± 2 °C), using alkoxysilanes: tetraethoxysilane (TEOS), as the silica source, and ethoxydimethylvinylsilane (DMVES), triethoxyoctylsilane (OTES), and trimethoxyhexadecylsilane (HDTMES), as modifier agents. The obtained materials were characterized (either as powders or as thin films) by Fourier-transform infrared spectroscopy (FTIR), UV/Vis spectroscopy, transmission electron microscopy (TEM), thermogravimetric analysis (TGA), atomic force microscopy (AFM), spectroscopic ellipsometry (SE), and water contact-angle measurements. UV/Vis spectra showed that the PVC substrate coated with the silica material containing TEOS/DMVES/OTES had a transmittance of about 90% in the wavelength range of 650–780 nm. The water contact angles increased from 83° for uncoated PVC substrate to ~94° for PVC substrates coated with the sol–gel silica materials. These PVC films with hybrid silica coatings can be used as the materials for outdoor applications, such as energy-generating solar panel window blinds or PVC clear Windmaster outdoor blinds.

Solid-state NMR studies of non-ionic surfactants confined in mesoporous silica

This review gives an overview of current trends in the investigation of confined molecules such as higher alcohols, ethylene glycol and polyethylene glycol as guest molecules in neat and functionalized mesoporous silica materials. All these molecules have both hydrophobic and hydrophilic parts. They are characteristic role-models for the investigation of confined surfactants. Their properties are studied by a combination of solid-state NMR and relaxometry with other physicochemical techniques and molecular dynamics techniques. It is shown that this combination delivers unique insights into the structure, arrangement, dynamical properties and the guest-host interactions inside the confinement.

Advanced Sample Preparation Techniques for Surface Spectroscopy Analysis of Organic: Inorganic Hybrid Silica Particles

Silica due to its large inorganic amorphous wall and hydrophilic surface properties renders its suitability for designing different varieties of organic–inorganic silica-based materials. Characterization of such hybrid silica-based materials is one of the fascinating as well as challenging topics to be covered. Surface analysis of these hybrid materials can be done utilizing various techniques, out of which X-ray photoelectron spectroscopy (XPS), 29Si Solid-state Nuclear magnetic resonance (NMR) spectroscopy, and Fourier-transform infrared spectroscopy (FTIR) is the most ideal ones. Thus, before analyzing these silica materials, it requires a massive study on its sample preparation for appropriate characterization of the organic molecules present in the inorganic network. Hence, this chapter will give a brief elucidation of the sample preparation techniques for analyzing the hybrid materials utilizing the above instrumentation techniques.

Cu(I) removal using mesoporous silica (UGM-triamin)

This paper shows the syntheses and use of hybrid porous silica materials (UGM-triamin) in the adsorption of Cu (I) of the cyanidation effluents of gold and silver. Studies of adsorption of Cu (I) in synthetic solutions of Cu-CN a pH of 11 and at a concentration ratio of 1: 5 Cu: CN, simulating the effluents of cyanide process gold and silver ores, showed maximum adsorption capacity of 7.54 mg of Cu (I) per gram of material and favorable adsorption according to the Langmuir model (RL of 0.31 to 0.41). The evaluation of the adsorption capacity of the material with real solutions of cyanide, showed 95% removal of copper in the effluent cyanide and 68.5% selectivity for the adsorption of copper. It has been observed free cyanide destruction in the system during adsorption of copper, so that the oxidation of free cyanide may be linked to the mechanism of adsorption of copper.

Recovering Nutrients from Waste Black Water Through Multi-Functional Mesoporous Silica

In order to prevent the harmful effects in water phase such as eutrophication, industrial and urban sewages must be treated before discharging into the aquatic environment. In this work, amine grafted magnetic nanoporous silica materials are synthesized and applied as an adsorbent for the recovery of nutrients from waste black water. The magnetic force could separate the surface func-tionalized nanoporous silica materials from aqueous medium after treatment, and showed the higher adsorption capacity of nutrients than that of the original mesoporous silica. The multi-functional nanoporous silica adsorbents were effectively removed phosphate and nitrate at 20 °C with the maximum adsorption capacities of 42.5 and 34.9 mg/g, respectively. The overall results indicated that the synthesized multi-functional nanoporous silica sorbents can be a candidate material for the nutrient recovery in wastewater treatment system.

A Review on the Application of Zeolites and Mesoporous Silica Materials in the Removal of Non-Steroidal Anti-Inflammatory Drugs and Antibiotics from Water

Zeolites and mesoporous silica materials are effective adsorbents that can be useful for the removal of various pharmaceuticals including non-steroidal anti-inflammatory drugs and antibiotics from low-quality water. This paper summarizes the properties and basic characteristics of zeolites and mesoporous silica materials and reviews the recent studies on the efficacy of the adsorption of selected non-steroidal medicinal products and antibiotics by these adsorbents to assess the potential opportunities and challenges of using them in water treatment. It was found that the adsorption capacity of sorbents with high silica content is related to their surface hydrophobicity (hydrophilicity) and structural features, such as micropore volume and pore size, as well as the properties of the studied medicinal products. This review can be of help to scientists to develop an effective strategy for reducing the amount of these two groups of pharmaceuticals in wastewater.