Titanium chloride, adsorption

Gold, chloride, adsorption, magnetite, goethite, alumina, titanium dioxide, hydrometallurgy... 

Kazarinov et al. have investigated the adsorption of CIO4, Cl, HSO4 and H2PO4 ions on titanium dioxide by means of the radioactive tracer method. These authors employed the Ti02 films prepared by thermal decomposition of titanium chloride (so, in principle, similar to those used in above mentioned XPS studies ). 

Due to its ability to withstand high pressure, its relative low cost, and inertness, stainless steel has become the standard material of columns and other chromatographic components. However, under certain circumstances, stainless steel has been shown to interact with the sample and the mobile phase [39]. The best known example is chloride salt corrosion of stainless steel. Data indicate that nearly all common eluents dissolve iron from stainless steel [39]. It appears that proteins also adsorb to stainless steel [39], The adsorption process is fast, whereas desorption is slow, a result which leads to variable protein recoveries. A number of manufacturers are offering alternatives to stainless components with Teflon -lined columns and Teflon frits. Titanium is being explored as an alternative to stainless steel. A cheaper and simpler procedure is to oxidize the surface of the stainless steel with 6N nitric acid. This procedure should be repeated about every 6 months. 

Surface concentration (Np), the ranges of particles Pd sizes (d) and average sizes of Pd particles (da) for Ti02-Pd films synthesized by combined pyrolysis of palladium chloride and titanium resinate (RTi) on air at 450°C (1 h) and then annealed in hydrogen at 500°C and 800°C for 1 h, by vacuum deposition of Pd and by adsorption of Pd2+ ions on TiOz film obtained by pyrolysis of titanium resinate... 

EC is a simple, efficient, and promising method to remove arsenic form water. Arsenic removal efficiencies with different electrode materials follow the sequence iron > titanium > aluminum. The process was able to remove more than 99% of arsenic from an As-contaminated water and met the drinking water standard of 10p,gL 1 with iron electrode. Compared with the iron electrodes, aluminum electrodes obtained lower removal efficiency. The plausible reason for less arsenic removal by aluminum in comparison to iron could be that the adsorption capacity of hydrous aluminum oxide for As(III) is much lower in comparison to hydrous ferric oxides. Comparative evaluation of As(III) and As(V) removal by chemical coagulation (with ferric chloride) and electrocoagulation has been done. The comparison revealed that EC has better removal efficiency for As(ni), whereas As(V) removal by both processes was nearly same (Kumar et al. 2004). 

SAFETY PROFILE A highly corrosive irritant to the eyes, skin, and mucous membranes. Mildly toxic by inhalation, Explosive reaction with alcohols + hydrogen cyanide, potassium permanganate, sodium (with aqueous HCl), tetraselenium tetranitride. Ignition on contact with aluminum-titanium alloys (with HCl vapor), fluorine, hexa-lithium disilicide, metal acetylides or carbides (e.g., cesium acetylide, rubidium ace-tylide). Violent reaction with 1,1-difluoro-ethylene. Vigorous reaction with aluminum, chlorine + dinitroanilines (evolves gas). Potentially dangerous reaction with sulfuric acid releases HCl gas. Adsorption of the acid onto silicon dioxide is exothermic. See also HYDROGEN CHLORIDE (AEROSOL) and HYDROCHLORIC ACID. 

Schering-Plough Corp, has used an oxazolidinone in its synthesis of the cholesterol adsorption inhibitor (+)-SCH 54016 (24) (Scheme 7) [51], Condensation of an acid chloride intermediate with the (7 )-phenylglycine-derived Evans auxiliary followed by reaction of the titanium enolate with -(4-methoxybenzyh-dene)anihne gave the intermediate 25. This was silylated and treated with TBAF, resulting in removal of the auxiliary and cyclization to form the 2-azetidinone ring. The stereochemistry was exclusively trans. The azetidinone was then converted to the bromide, followed by intramolecular alkylation to form SCH 50416 in > 99% ee. 

Iron-molybdenum-titanium oxides were prepared via the sol-gel method. Either (NH4)6Mo7024 4H20, and ferric nitrate (FeN), Fe(N03)3-9H20, or FeCb and MoOCL were used as precursors together with Ti-isopropoxide. These solids were characterised by chemical analysis and N2 adsorption. The sol-gel samples developed higher surface areas (c.a. 100 m g ), except for the sol-gel solid prepared with Fe and Mo chlorides as precursors, than those prepared by impregnation. 

Examples The roasting of ores, the chemical adsorption of hydrogen sulfide by metal oxides (forming sulfides), the conversion of a metal oxide with a volatile non-metal oxide into a salt (e.g., the chemical adsorption of sulfur dioxide and oxygen by calcium oxide), the reductive chlorination of ilmenite (iron titanate) whereby iron chloride and titanium oxide are formed. In some processes a second solid reactant is present (e.g., carbon) that also reacts with the gaseous reactant, forming another gaseous reactant (e.g., carbon monoxide). 

As another example, consider the dissociative adsorption of hydrogen chloride on titanium oxide. The gas molecule undergoes a heterolytic rupture to provide a chloride ion that is placed in the interstitial position and a hydrogen ion that is... 

Schindler, RW. (1967) Heterogeneous equilibria involving oxides, hydroxides, carbonates and hydroxide carbonates. Equilibria concepts in natural water systems. Adv. Chem. Sen, 67, 196-221. Schmidt, J. and Vogelsberger, W. (2009) Aqueous long-term solubility of tita-nia nanoparticles and titanium(IV) hydrolysis in a sodium chloride system studied by adsorptive stripping voltammetry. /. Solution Chem., 38, 1267-1282. Schuiling, R.D. and Vink, B.W. (1967)... 

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