Colloidal Stabilization of Submicron-Sized Zeolite NaA in Ethanol-Water Mixtures for Nanostructuring into Thin Films and Nanofibers

2023-01-10
Gözcü, Oğuz
Kayacı, H. Utkucan
Dou, Yibo
Zhang, Wenjing
Hedin, Niklas
Jasso-Salcedo, Alma B.
Kaiser, Andreas
Çınar, Simge
Despite the growing use of organic or mixed solvents in zeolite processing, most studies focus only on aqueous suspension systems. We investigated the colloidal characteristics of submicron-sized zeolite NaA in mixed ethanol-water solvents. The effects of the mixing ratio of solvents and various additives on the dispersion of the zeolite powders were studied. The zeolite NaA particles were destabilized in solvent mixtures at a high ethanol-to-water ratio, a reduction in the zeta potential was observed, and the destabilization was rationalized by the Derjaguin, Landau, Verwey, Overbeek (DLVO) theory. An improved stabilization of the zeolite NaA suspensions was achieved in ethanol-rich solvent mixtures using nonionic low molecular weight organic additives, but not with their ionic counterparts such as anionic, cationic surfactants or inorganic acids or bases. Polyethylene glycol (PEG)-400 was found to be a good dispersant for the submicron-sized zeolite NaA particles in the ethanol-water mixtures, which was attributed to its interaction with the zeolite surface, leading to an increased zeta potential. The PEG-stabilized zeolite suspensions led to low suspension viscosities as well as uniform and consistent spin-coated films.

Suggestions

HYGRIC PERFORMANCE ASSESSMENT OF AUTOCLAVED AERATED CONCRETE TREATED WITH NANO DISPERSIVE CALCIUM HYDROXIDE SOLUTION
Tanideh, Gelareh; Tavukçuoğlu, Ayşe; Saltık, Emine Nevin; Department of Architecture (2022-2)
The focus of the study is to uncover whether the treatment of autoclaved aerated concrete (AAC) surface with alcohol dispersion of calcium hydroxide Ca(OH)2 nanoparticles controls its high water absorption properties to some extent or not. AAC as a lightweight and porous concrete material, is well-known for its high breathing and thermal resistivity features while it suffers from high water absorption and capillary suction in exposed conditions. Laboratory analyses were conducted on four types of AAC, used ...
Electrochemical behaviour and electrochemical polymerization of fluoro-substituted anilines
Cihaner, A; Önal, Ahmet Muhtar (2002-08-01)
The electrochemical behaviour of three fluoro-substituted aniline monomers, 2-fluoroaniline (2FAN), 3-fluoroaniline (3FAN) and 4-fluoroaniline (4FAN), was investigated in aqueous acidic and organic media by means of cyclic voltammetry (CV) studies. Constant potential electrolysis (CPE) of the monomers in acetonitrile-water mixture (1: 1 by volume) using NaClO4 as supporting electrolyte yielded soluble polymers. The mechanism of electrochemical polymerization was investigated using in situ electron spin reso...
Phase transition of chemically synthesized FePt nanoparticles under high pressure
ŞİMŞEK, TELEM; Karci, Ozgur; ÖZCAN, ŞADAN (The Scientific and Technological Research Council of Turkey, 2018-01-01)
We present the results of a study related to phase transformation of chemically synthesized FePt nanoparticles under high pressure from face-centered cubic into face-centered tetragonal structure. As-synthesized nanoparticles are around 4.5 nm and show superparamagnetic behavior at 300 K. After annealing under 60 bar pressure of hydrogen at 400 degrees C for 2 h, nanoparticles exhibit strong ferromagnetic behavior with 5391 Oe coercivity. Results show that high-pressure annealing lowers the decomposition te...
Pervaporation of ethanol/water mixtures by zeolite A membranes synthesized in batch and flow systems
Arıcan Yüksel, Berna; Çulfaz, Ali; Kalıpçılar, Halil; Department of Chemical Engineering (2011)
Zeolite A membranes have great potential in pervaporation separation of ethanol/water mixtures with high flux and selectivity. Zeolite membranes usually synthesized from hydrogels in batch systems. In recent years, zeolite membranes are prepared in semicontinuous, continuous and recirculating flow systems to allow the synthesis of zeolite membranes with enlarged surface areas and to overcome the limitations of batch system at industrial level production. The purpose of this study is to develop a synthesis m...
Design rules for suspending concentrated mixtures of solids in stirred tanks
Ayrancı Tansık, İnci (2011-10-01)
This study examines complete off-bottom suspension conditions for slurries containing mixtures of solids at a wide range of concentrations. Binary combinations of five different particles; bronze, two sizes of glass beads, ion exchange resin, and nickel were tested with two impellers: the Lightnin A310 and the down pumping 45 degrees PBT. The effect of particle size ratio and density ratio of the two solid phases on N(js) was investigated. Solids loadings were varied from 3 to 56 wt% (weight percent) with w...
Citation Formats
O. Gözcü et al., “Colloidal Stabilization of Submicron-Sized Zeolite NaA in Ethanol-Water Mixtures for Nanostructuring into Thin Films and Nanofibers,” Langmuir, vol. 39, no. 1, pp. 192–203, 2023, Accessed: 00, 2023. [Online]. Available: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85144417821&origin=inward.