Adsorption of reactive yellow BF-3R dye by CTABr modified zeolite NaY

Textile industries generate effluents composed of organic salts and complexes from dyes not fixed on fabrics, or not degraded by the inefficiency of conventional treatment processes, which represents a high potential for environmental impact due to inadequate disposal of the generated effluent. Zeolites are porous materials that have a three-dimensional structure containing tetrahedrals of AlO4 e SiO4 which can be modified to improve its properties. The adsorption process using zeolites as adsorbents can be considered an excellent economic physical treatment to solve or minimize such a problem. This work presents an experimental study focusing on the preparation and characterization of zeolite NaY and modified with organic surfactant cetyltrimethylammonium bromide (CTABr) intended to be used as adsorbent in the process of removing yellow dye BF-3R in dye-water system batch system. The samples were characterized by X-ray diffraction (XRD), Infrared spectroscopy (IR) and thermogravimetry (TG). The effect of process parameter such as pH was studied. Results revealed that even though the modified cetyltrimethylammonium bromide organic surfactant (CTABr) did not cause alterations on the zeolite NaY structure. The IR results revealed that CTABr was successfully incorporated to zeolite NaY structure. The best conditions were established with respect to pH to saturate the available sites located on the zeolite NaY and NaY_CTABr surface. The maximum adsorption capacities were 3.35 and mg/g for dye 5.35 using as-synthesized zeolite NaY and CTABr modified zeolite NaY. Modified zeolites are excellent adsorbents for removing reactive dyes from industrial wastewater.

Synthesis, Characterization, and Photocatalytic Activity of N-Doped TiO2/Zeolite-NaY for Methylene Blue Removal

Dye is an important compound in textile industry. The famous dye for coloring of textile is methylene blue. Methylene blue degradation has been difficult when carried out naturally by microorganisms. The advanced oxidative process is a promising method to degrade methylene blue using semiconductor material TiO2 and its modification. The modification catalyst of TiO2 such as TiO2-N, TiO2/zeolite-NaY and TiO2-N/zeolite-NaY. These materials were synthesized by mixing TiO2 and urea, then followed by impregnation of the mixture to zeolite-NaY as support material. The materials have been synthesized then characterized by XRD, and FTIR. Degradation of methylene blue on the synthesized materials was tested under UV light for 5, 20, 30, 40, and 50 minutes. The results showed that the diffractogram of TiO-N/zeolite-NaY and TiO2/zeolite-Y has a similar spesific peak with TiO2 and zeolite-NaY. It indicates that the impregnation process was sucessfully. TiO2/zeolite-NaY and TiO2-N/zeolite-NaY also showed the excellent activity for degrading methylene blue, which reached up to 99% for 3 hours of reaction.

Photocatalytic Activity and Kinetic Study of Methylene Blue Degradation using N-Doped TiO2 with Zeolite-NaY

<p class="E-JOURNALAbstractBodyEnglish">Methylene blue is the most widely used dye in the industry and it is difficult to be degraded by the microorganism. This research aims to investigate the photocatalytic activity and effects of contact time on the photocatalytic degradation rate of methylene blue by TiO₂/Zeolite-NaY and TiO₂-N/Zeolite-NaY material based on the kinetic study. The Advanced Oxidative Process (AOP) method was used to degrade methylene blue. Furthermore, the AOP is a degradation process that uses semiconductor material such as TiO₂ or modification catalyst of TiO₂to be TiO₂/Zeolite-NaY and TiO₂-N/Zeolite-NaY. The degradation of methylene blue with catalyst TiO₂/Zeolite-NaY and TiO₂-N/Zeolite-NaY were tested under UV light for 5, 20, 30, 40, and 50 minutes. The result showed that TiO₂/Zeolite-NaY and TiO₂-N/Zeolite-NaY had an excellent activity for degrading the dye, which reached up to 99% after 20 and 30 minutes reaction, respectively. Also, a kinetic study of methylene blue degradation on TiO₂/Zeolite-NaY and TiO₂-N/Zeolite-NaY showed the kinetic models were according to pseudo-second-order.</p>

Zeolite NaY-Copper Composites Produced by Sintering Processes for Adsorption Heat Transformation—Technology, Structure and Performance

In adsorption heat pumps, the adsorbent is typically combined with heat conducting structures in order to ensure high power output. A new approach for the direct integration of zeolite granules into a copper structure made of short copper fibers is presented here. Zeolite NaY granules with two different grain sizes are coated with copper fibers and powder and sintered to larger structures. The sorption dynamics of these structures were measured and evaluated in terms of heat and mass transfer resistances and compared to the loose grain configuration of the same material. We found that the thermal conductivity of such a composite structure is approximately 10 times higher than the thermal conductivity of an adsorbent bed with NaY granules. Sorption equilibrium measurements with a volumetric method indicate that the maximum uptake is not altered by the manufacturing process. Furthermore, the impact of the adsorbent–metal structure on the total thermal mass of an adsorption heat exchanger is evaluated. The price of the superior thermal conductivity is a 40% higher thermal mass of the adsorption heat exchanger compared to the loose grain configuration.

Antimicrobial and Hemostatic Activities of Cotton-Based Dressings Designed to Address Prolonged Field Care Applications

ABSTRACT Introduction Developing affordable and effective hemostatic and antimicrobial wound dressings for prolonged field care (PFC) of open wounds is of interest to prevent infection, to prevent sepsis, and to conserve tissue viability. The need for an effective hemostatic dressing that is also antimicrobial is required of a hemostatic dressing that can be left in place for extended periods (days). This is particularly important in light of the existence of pathogens that have coagulopathy properties. Thus, dressings that provide effective hemostasis and reduction in the frequency of dressing changes, whereas exerting robust antimicrobial activity are of interest for PFC. Highly cleaned and sterile unbleached cotton has constituents not found in bleached cotton that are beneficial to the hemostatic and inflammatory stages of wound healing. Here, we demonstrate two approaches to cotton-based antimicrobial dressings that utilize the unique components of the cotton fiber with simple modification to confer a high degree of hemostatic and antimicrobial efficacy. Methods Spun bond nonwoven unbleached cotton was treated using traditional pad dry cure methods to add ascorbic acid, zeolite (NaY) with pectin, calcium chloride, and sodium carbonate/calcium chloride. Similarly, nanosilver-embedded cotton fiber was blended with pristine cotton fibers at various weight ratios to produce hydroentangled nonwoven fabrics. The resulting treated fabrics were assessed for hemostasis using thromboelastographic clotting assays and antimicrobial activity utilizing American Association of Textile Chemists and Colorists 100. Results Zeolite-containing dressings possessed significant hemostatic activity, whereas ascorbic acid- and silver-containing dressings reduced Gram-positive and Gram-negative organism numbers by several logs. Conclusion Based on this study, a multilayered hemostatic dressing with antimicrobial properties is envisioned. This dressing would be safe, would be economical, and have a stable shelf-life that would be conducive for using PFC.

Separating a linear C5 hydrocarbon from a branched C6 hydrocarbon: n-pentane from 2,2-dimethyl butane using levitation and blow torch effects

A mixture of n-pentane and 2,2-dimethyl butane can be separated to a very high purity using zeolite NaY. This can be achieved by a judicious combination of levitation and blow torch effects. The separation uses very little energy.

OXIDATIVE CONVERSION OF LOWER OLEFINS AND PARAFFINS OVER THE MODIFIED ZEOLITE CATALYSTS

With the purpose of development of high efficiency catalysts for reactions of the oxidative conversion of lower olefins and paraffins into the desired products of petrochemical industry it has been synthesized by ion exchange method a range of the metalzeolite catalysts on the basis of synthetic (NaY) and natural (pure and dealuminated clinoptilolite and mordenite) zeolites and the cations of different metals. It has been established that the metalzeolite catalysts prepared on the basis of synthetic zeolite NaY shows relatively high activity in the oxidative conversion of ethylene and propylene into acetaldehyde and acetone accordingly. It has been also synthesized a highly effective metalzeolite catalysts for the processes: oxidative conversion of methane into ethylene; oxidative conversion of propane into acetaldehyde and formaldehyde; oxidative conversion of methane to ethylene and acetylene; oxidative conversion of methane to 1,4-butanediol