ВЫДЕЛЕНИЕ КОНЦЕНТРАТА ЛАНТАНА И ЦЕРИЯ ИЗ ОТРАБОТАННОГО КАТАЛИЗАТОРА КРЕКИНГА ФТОРИДНЫМ СПОСОБОМ

В работе рассматриваются факторы, влиющие на максимальное выделение концентрата лантана и церия из отработанного катализатора крекинга по фторидной технологии. Их содержание в отработанном катализаторе крекинга сопоставимо в содержанием в промышленно перерабатываемых рудах. Используются в качестве вскрывающих агентов серной кислоты и фторида аммония. Использованы такие методы, как ИК-спектроскопия, рентгенофлуоресцентный анализ, сканирующая электронная микроскопия. В результате получен концентрат лантаноидов, которые содержатся в виде фторидов. Концентрация лантаноидов возрастает в несколько раз. The article discusses the factors influencing the maximum release of lanthanum and cerium concentrate from a spent cracking catalyst using fluoride technology. Their content in the spent cracking catalyst is comparable to the content in industrially processed ores. They are used as the opening agents of sulfuric acid and ammonium fluoride. Methods such as IR spectroscopy, X-ray fluorescence analysis, scanning electron microscopy were used. As a result, a concentrate of lanthanides was obtained, which are contained in the form of fluorides. The concentration of lanthanides increases several times.

Morphological and Optical Characterization of Colored Nanotubular Anodic Titanium Oxide Made in an Ethanol-Based Electrolyte

In this paper, the possibility of color controlling anodic titanium oxide by changing anodizing conditions of titanium in an ethanol-based electrolyte is demonstrated. Colored anodic titanium oxide was fabricated in an ethanol-based electrolyte containing 0.3 M ammonium fluoride and various amounts of deionized water (2, 3.5, 5, or 10 vol%), at voltages that varied from 30 to 60 V and at a constant anodization temperature of 20 °C. Morphological characterization of oxide layers was established with the use of a scanning electron microscope. Optical characterization was determined by measuring diffusion reflectance and calculating theoretical colors. The resulting anodic oxides in all tested conditions had nanotubular morphology and a thickness of up to hundreds of nanometers. For electrolytes with 3.5, 5, and 10 vol% water content, the anodic oxide layer thickness increased with the applied potential increase. The anodic titanium oxide nanotube diameters and the oxide thickness of samples produced in an electrolyte with 2 vol% water content were independent of applied voltage and remained constant within the error range of all tested potentials. Moreover, the color of anodic titanium oxide produced in an electrolyte with 2 vol% of water was blue and was independent from applied voltage, while the color of samples from other electrolyte compositions changed with applied voltage. For samples produced in selected conditions, iridescence was observed. It was proposed that the observed structural color of anodic titanium oxide results from the synergy effect of nanotube diameter and oxide thickness.

Electrochemical Anodization and Characterization of Titanium Oxide Nanotubes for Photo Electrochemical Cells

Due to its multitude of applications, titanium oxide is one of the most coveted and most sought-after materials. The above experiment demonstrated that TiO2 nanotube arrays might be formed by electrochemical anodization of titanium foil. The 0.25 wt% ammonium fluoride (NH4F) was added to a solution of 99% ethylene glycol. Anodization is carried out at a constant DC voltage of 12V for 1 hour. Then, the annealing process is carried out for 1 hour at 4800C, which is known as an annealing. FE-SEM were utilized to evaluate the surface morphology of the nanotube arrays that were made. At the wavelength of 405 nm, sharply peaked photoluminescence intensity was observed, which corresponded tothe band gap energy (3.2 eV) of the anatase TiO2 phase. Since free excitations appear at 391 and 496 nm, and since oxygen vacancies are developed on the surface of titania nanotube arrays, it is reasonable to conclude that free excitations and oxygen vacancies are the causes of humps at 391 and 496 nm, and that they may also be present at 412 and 450 nm. FESEM results showed uniformly aligned TiO2 nanotube arrays with an inner diameter of 100 nm and a wall thickness of 50 nm