Titanium dioxide analysis

The second form consists of Pt metal but the iridium is present as iridium dioxide. Iridium metal may or may not be present, depending on the baking temperature (14). Titanium dioxide is present in amounts of only a few weight percent. The analysis of these coatings suggests that the platinum metal acts as a binder for the iridium oxide, which in turn acts as the electrocatalyst for chlorine discharge (14). In the case of thermally deposited platinum—iridium metal coatings, these may actually form an intermetallic. Both the electrocatalytic properties and wear rates are expected to differ for these two forms of platinum—iridium-coated anodes. 

The analytical chemistry of titanium has been reviewed (179—181). Titanium ores can be dissolved by fusion with potassium pyrosulfate, followed by dissolution of the cooled melt in dilute sulfuric acid. For some ores, even if all of the titanium is dissolved, a small amount of residue may still remain. If a hiU analysis is required, the residue may be treated by moistening with sulfuric and hydrofluoric acids and evaporating, to remove siUca, and then fused in a sodium carbonate—borate mixture. Alternatively, fusion in sodium carbonate—borate mixture can be used for ores and a boiling mixture of concentrated sulfuric acid and ammonium sulfate for titanium dioxide pigments. For trace-element deterrninations, the preferred method is dissolution in a mixture of hydrofluoric and hydrochloric acids. 

The reduction of gun erosion by the use of additives to the gun powder has been studied at the US Naval Ordnance Station (NOS), Indian Head, Md. During the investigation of one of the additives, namely titanium dioxide (Ti02) or Swedish additive, it was necessary to determine small amts of Ti in gun powder residues taken from the gun after firing. As only very small amts of Ti were expected in the samples, the very sensitive technique of NAA was used for the analysis (Ref 2)... 

We have developed a compact photocatalytic reactor [1], which enables efficient decomposition of organic carbons in a gas or a liquid phase, incorporating a flexible and light-dispersive wire-net coated with titanium dioxide. Ethylene was selected as a model compound which would rot plants in sealed space when emitted. Effects of the titanium dioxide loading, the ethylene concentration, and the humidity were examined in batches. Kinetic analysis elucidated that the surface reaction of adsorbed ethylene could be regarded as a controlling step under the experimental conditions studied, assuming the competitive adsorption of ethylene and water molecules on the same active site. 

The near-UV illuminated titanium dioxide (anatase) powder flow reactor, as well as the gas chromatographic methods for analysis of effluents, has been described in detail earlier [2]. The procedvu-es followed were substantially those of Luo and OUis [1], and Sauer et al. [2]. 

Almost all fiber and partial titanium dioxide can be recovered from white water by DAF under full flow pressurization mode43 with chemical addition. On June 10, 1982, at Mead Corporation, pulp was prepared with 40% cotton fiber and 60% wood fiber. The loading of titanium dioxide was about 50% (i.e., 273 kg Ti02 per 600 kg total pulp). The white water from No. 2 machine was fed to a DAF cell (diameter = 3 m) at 15.8 L/s (250gal/min) under full flow pressurization mode. Turkey red oil (TRO) was dosed as a flotation aid at 80mL/min. The influent white water (before TRO addition), DAF effluent, and floated scum were sampled for analysis. The DAF influent had 98 mg/L of TSS, and 650 NTU of turbidity at pH 9.27. The DAF effluent had 15 mg/L TSS and 550 NTU of turbidity at pH 9.25. Although TSS (fiber and titanium dioxide) recovery rate was 85%, the ash content (titanium dioxide) of the recovered TSS was very low. Therefore, using a DAF clarifier under full flow pressurization mode and TREO, the majority of fibers in white water but only about half of titanium dioxide can be recovered. 

Metal Analysis of Commercial Titanium Dioxide Pigments... 

In conclusion, the paint sample was comprised of 63.3 wt% solids (polymers and fillers) and 36.7 wt% solvent. The solids were likely comprised of calcium carbonate and titanium dioxide at 12.6 and 17.7 wt%, respectively, of the total sample including solvent. The calcium carbonate and titanium dioxide were calculated based on the measured levels of calcium and titanium from the ICP analysis. Not counting the calcium and titanium levels there is 4.9 wt% of additional metals present. Based on the calcium carbonate level and titanium dioxide level along with the remaining percentage of metals present, 34.9 wt% of the total sample is accounted for. Therefore, the maximum level of alkyd in the sample is 28.4 wt%. TGA is recommended in order to quantify the level of alkyd and total level of mineral fillers in the dried paint sample. 

Bello J.M., Stokes D.L., Vo-Dinh T., Titanium-dioxide based substrate for optical monitors in surface-enhanced Raman-scattering analysis, Anal. Chem. 1989 61 1779-1783. 

Applying ion beams, surface-sensitive analysis and modification in atomic and electronic structures of inorganic materials have been developed. Ion beam modification of titanium dioxide (Ti02), carbon-based materials, and the analysis of Nb/Cu multilayers and VO2 using ion beam are described as follows. 

Majcen et al. [93] studied linear and nonlinear multivariate analysis in the quality control of industrial titanium dioxide white pigment using XRF spectrometry. 

Titanium was discovered in 1791 by William Gregor, an English clergyman and amateur chemist. He identified it in a black sand (now known to be ilmenite) sent to him for analysis from the Menacchan Valley in Cornwall. Four years later, the famous German chemist Klaproth rediscovered the element in the ore rutile, one form of titanium dioxide. He gave it the name titanium after the Titans who in Greek mythology were the sons of Earth. 

The crystal structure of the pigments is determined by X-ray analysis which is sensitive enough to determine 0.3-0.5% anatase in the presence of 99.7-99.5% rutile. For standards, see Table 1 (Titanium dioxide pigments Methods of analysis and Specification ). 

Following the guidelines established by Schechter s work, we dispersed titanium dioxide particles in 1% solutions of carboxylated styrene-butadiene block copolymers and stirred the dispersions at elevated temperatures in a nitrogen atmosphere. Typical data are shown in Table I. The dispersions (primary dispersions) in o-dichlorobenzene were quite stable. The titanium dioxide particles were isolated from these primary dispersions by centrifugation and were washed with toluene and finally with methanol. After drying in vacuo, samples of the block copolymer-titanium dioxide composites were submitted for carbon analysis. The... 

Liang, P. and Liu, R. (2007) Speciation analysis of inorganic arsenic in water samples by immobilized nanometer titanium dioxide separation and graphite furnace atomic absorption spectrometric determination. Analytica Chimica Acta, 602(1), 32-36. 

Clegg, I.M. Everall, N.J. King, B. Melvin, H. 8t Norton, C. On-Line Analysis Using Raman Spectroscopy for Process Control During the Manufacture of Titanium Dioxide Appl. Spectrosc. 2001, 55, 1138-1150. 

X-ray Diffraction Analysis. The inorganic components of paper are the most suitable ones for quantitative X-ray diffraction analysis. Most of these compounds are minerals and are present as fillers, coatings and pigments (often whiteners) which are added to improve the properties of the paper. Examples of compounds commonly added to paper are alumina, aluminum silicate, barium sulfate, calcium carbonate, calcium sulfate, calcium sul-foaluminate, iron oxide, magnesium silicate, silica, titanium dioxide, zinc oxide, and zinc sulfide (28). Some of these, e.g., calcium carbonate and titanium dioxide, may be present in any of... 

From the analysis of their experimental results of the investigation of the charge carrier recombination kinetics in titanium dioxide colloidal solutions and in dispersions Serpone et al. and Bowman and co-workers have also assumed the existence of two different traps [5,6]. 

XRD analysis of the xerogels obtained by drying pure titanium dioxide sol at 70°C showed the presence of the nanocrystalline anatase phase [109]. Thermal treatment of this xerogel resulted in the growth of anatase crystallites up to 400°C. The anatase-to-rutile transformation began to occur at 450-500°C. This process was practically completed at 700°C, and only rutile phase existed at rcaic > 700°C. This feature of Ti02 xerogels is typical and well known (see, for example, [109]). Thus, it can be concluded that anatase-rutile transition temperature of nanosized particles is considerably lower than that of the... 

XRD analysis could also provide interesting information regarding the inorganic materials formed during the carbonization process in complex formulations.28,36 As an example, in the case of intumescent coatings, the formation of titanium pyrophosphate resulting from the reaction between APP and titanium dioxide can be demonstrated (Figure 10.17). 

Harkins and Dahlstrom1 have carried out a very interesting analysis of the heat of wetting of titanium dioxide by various pure and mixed liquids. The heat evolved on immersion of the dry powder in dry benzene or other hydrocarbon is small if butyric acid, or alcohols, or water are present, in very small amounts, the heat evolved is about doubled esters produce an increase in the heat of wetting, but less than compounds with OH or COOH groups. The maximum heat appears to be evolved as soon as enough of these polar substances are present to form a layer one molecule thick on the surface of the powder. This seems to indicate that the affinity of the solid surface is practically completely satisfied when a layer one molecule thick of butyric acid is adsorbed, so that nearly all the heat of adsorption arises from the adhesion of this layer. 

Materials. The titanium dioxide powders were rutile in structure (obtained from the Titanium Division, National Lead Co., Amboy, N. J.), with nominal specific surface areas of 10 and of 100 sq. meters per gram. Chemical analysis by the supplier showed negligible impurities except for 0.8% sodium oxide in the Ti02-100 and traces of iron in both the TiO2-10 and the TiO2-100. The presence of iron was confirmed by the nature of the decay of the neutron irradiation—induced radioactivities. 

Many paints require vigorous pre-treatment before the matrix can be destroyed. Even after considerable oxidation it may be necessary to filter off titanium dioxide. Some paints are, however, more amenable to acid dissolution. Eider [147] reported that it was possible to determine barium, cadmium, calcium, cobalt, lead, magnesium, manganese, mercury, tin, zinc and zirconium in vinyl additives and paint (1 g) by dissolution in hot concentrated nitric acid (10 ml). The mixture was filtered and made up to 100 ml. Liquid samples were again dissolved in MIBK (lg in 100 ml). Air/ acetylene and nitrous oxide/acetylene flames were used to complete the analysis as appropriate. Porter [148] reported losses of lead during the dry ashing of alkyd and latex paints and therefore recommended dissolution in either nitric/perchloric acids or nitric acid alone. 

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