Titanium electrode

The oxide coatings are porous and therefore the limitations on operating voltage for platinised titanium anodes apply as well to the oxide-coated titanium electrodes. It has been reported that breakdown of mixed metal oxide anodes may occur at 50-60 V in low-chloride concentration water but at only 10 V in chloride-rich environments . 

Lead sulfide, PbS, nanoparticulate thin films having pancake-like geometry and exhibiting ID quantum confinement, as controlled by the lowest dimension of the particles, have been synthesized by cathodic electrodeposition on TTO/glass and titanium electrodes from a pH 0.62 solution containing Pb(N03)2 and Na2S203 [162]. 

Rare, shiny, and lightest metal of the platinum group. Hardens platinum and palladium. The presence of 0.1 % of ruthenium in titanium improves its resistance to corrosion 100-fold. The spectacular catalytic properties of ruthenium are used on industrial scales (hydrogenations, sometimes enan-tioselective, and metathesis). Titanium electrodes coated with ruthenium oxide are applied in chlorine-alkaline electrolysis. Suitable for corrosion-resistant contacts and surgical instruments. 

The committee notes that the electrode damage may become more severe when feeds containing fluorine and chlorine are processed. In the fluoride transfer test discussed earlier, the titanium electrodes were severely corroded and the Pt coating was pitted or peeling off. This more severe damage would be unacceptable during full-scale plant operation. 

Excessive corrosion of platinum-plated titanium electrodes in the presence of fluorine-containing anolyte feed streams improvements in plating techniques are expected to solve this problem but have not yet been demonstrated. 

The oxidation of toluene to benzaldehyde (max. yield 98.8%) can be performed in a Ce(Cl04)3-HCl04-(Pt/Ti-Cu) system by using the in-cell method in an undivided cell [28]. Indirect electrooxidations of organic compounds with Ce(IV) are listed in Table 12 [221-230]. For the electrogeneration of Ce(IV), platinized titanium or platinum oxide-on-titanium electrodes are known to be suitable for continuous oxidation of Ce(III) in perchloric acid. 

The incident began during a normal mn when the operator noted an electrical short not long after the start of the melt. Standard shutdown procedures were initiated, and the titanium electrode was retracted at a rate of about 30 cm/min using a chain hoist. During shutdown, what proved later to be a water leak into the cmcible occurred with a concomitant pressure rise. Three mpture discs failed at about 4 bar. Some 2 min... 

Antonucci V, Giordano N, Bart JCJ (1982) Structure and photoelectrochemical efficiency of oxidized titanium electrodes. Int J Hydrogen Energy 7 769-774... 

Fig. 5.7 Time variation of titanium electrode etching current density for (a) Nitric acid/hydrofluoric acid electrolyte (b) Boric acid/nitric acid/hydrofluoric acid electrolyte.

The electrochemical reduction behavior of 1102 was also studied in a nitric acid-hydrazine solution at a titanium electrode because of its resistance to corrosion in nitric acid [59]. It was necessary to pretreat the titanium electrode, to remove surface oxide, through cathodic... 

The preparation of nickel oxide deposits with high surface area on steel, nickel, copper, graphite or titanium electrodes partly for anodic oxidation of organic compounds and the preparation of pressed nickel oxide powder electrodes mainly for application in storage batteries is described. The performance of nickel oxide anodes for batteries is improved by addition of cobaltflljhydroxide... 

FlG. 6. RuOi-coated extended melal titanium electrode for anodic chlorine evolution in the diaphragm and membrane process (courtesy of Heraeus Elektroden GmbH). 

C. Catalyst-Coated Titanium Electrodes for Oxygen Evolution from Acid Solutions... 

Most modern production uses a diaphragm cell, in which compartments containing steel and titanium electrodes are separated by porous diaphragms to isolate the products (Fig. 14.20). 

Into a freshly charged cell, as previously prepared, place 300 milliliters (10.1 fluid oz.) of ice-cold tap water into the anode compartment (clay pot), and then add and dissolve 50 grams (1.8 oz.) of sodium chlorate into this water. Thereafter, place 500 milliliters (17 fluid oz.) of ice-cold tap water into the cathode compartment, and then add and dissolve 50 grams (1.8 oz.) of sodium chlorate there into. Thereafter assemble the cell as illustrated below, and then place the cell into an ice bath, and then begin the electrolysis process. The desired dimensions of the titanium electrodes may vary, but it is recommended to use rectangular bars of 10 to 15 millimeters in width of surface area (0.39 inches by 0.59 inches), and the electrodes should be placed about 127 millimeters apart (5 inches). The current should be 1.5 to 2.7 volts DC current at about 50 amps. Over voltage should be minimum, and the cell temperature should be kept below 5 Celsius at all times. Electrolyze the solution for about 18 to 24 hours. 

Figure 29 Schematic showing the important electrochemical/chemical reactions occurring inside a creviced titanium electrode and on a Ti cathode coupled to the creviced electrode through a zero resistance ammeter.

Lapp, L. and Pletcher, D. (1997) Preparation and characterization of tin dioxide coated titanium electrodes. Electrochim. Acta 42, 1091-1099. 

Ribeiro, J. and De Andrade, A. R. (2004), Characterization of Ru02-Ta205 coated titanium electrode micro structure, morphology, and electrochemical investigation. J. Electrochem. Soc., 151(10) D106-D112. 

Chetty, R., Christensen, P.A., Golding, B.T. and Scott, K. (2004) Fundamental and applied studies on the electrochemical hydrodehalogenation of halogenated phenols at a palladised titanium electrode. Appl. Catal. A General 271, 185-194. 

Dow-Huron cell — Electrochemical cell for hydrogen peroxide production. A diaphragm-divided cell employing a carbon chips-PTFE composite as cathode material fed with air. At the anode oxygen is developed at, e.g., a platinized titanium electrode. 

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