Titanium platinized

DSA, lead, platinized titanium platinized titanium or niobium... 

In such cases basket anodes are frequently used. These have a relatively large surface and work at a low driving voltage due to their special construction. A cylinder of platinized titanium-expanded metal serves as the basket to which a titanium rod is welded. This serves as the current lead and carrier, and ends in a plastic foot that contains the cable lead and at the same time serves as the mounting plate. The expanded metal anode exhibits a very uniform anode current density distribution, even at large dimensions, in contrast to the plate anode. The reason is the many comers and edges of the metal that make the point effect only evident at the outer edges of the anode. 

A current with ripples can lead to a high consumption rate for platinized titanium anodes and their premature failure. The residual ripple should be limited to 5% (see Section 7.2.2) [7],... 

Galvanic or impressed current anodes are used to protect these components. The anode material is determined by the electrolyte zinc and aluminum for seawater, magnesium for freshwater circuits. Platinized titanium is used for the anode material in impressed current protection. Potential-regulating systems working independently of each other should be used for the inlet and outlet feeds of heat exchangers on account of the different temperature behavior. The protection current densities depend on the material and the medium. 

The internal cathodic protection of pipes is only economic for pipes with a nominal width greater than DIN 400 due to the limit on range. Internal protection can be achieved in individual cases by inserting local platinized titanium wire anodes (see Section 7.2.2). 

Partially platinized titanium impressed current anodes were chosen because contamination of the feed water by anodic decomposition products had to be avoided. Four pure zinc reference electrodes were installed in the tank to control and regulate the potential. The supports for the anodes were of polypropylene, which can operate for short periods up to 100°C, in contrast to the usual PVC supports used in cold water. 

Figure 21-1 shows the object to be protected and the arrangement of impressed current anodes and reference electrodes. A central anode and two ring anodes of platinized titanium wire 3 mm in diameter provided with additional copper wire conductors are installed here. It is worth noting that the central anode is suspended from a float, whereas the ring anode is mounted on plastic supports. The zinc reference electrodes are also on floats near the inner side of the bell, while the 17 reference electrodes are mounted on plastic rods on the bottom of the cup and in the ring... 

As anode material, smooth platinum in the form of a foil or net seems to be most universally applicable [32, 33]. In nonaqueous media, platinized titanium, gold, and nonporous graphite can also be used [56]. PbO -, MnOj- or FejO -anodes do not lead to Kolbe-dimers [57], except for PbO in acetic acid [58]. 

Spin trapping by PBN has also been employed to detect radical formation in a photo-Kolbe reaction in which acetic acid is irradiated (A > 360 nm) in the presence of platinized titanium dioxide powder (Kraeutler et al, 1978). The nitroxide observed was considered to be (PBN—Me ), but the published spectrum clearly shows the presence of a second species spectral overlap might therefore be an alternative to solvent polarity as an explanation of the discrepancy between the observed splitting parameters and those previously reported for this species. Where poor resolution obtains, it is important that... 

The anodes are platinized titanium (titanium plated with 5 microns of platinum) the cathodes are also titanium plated with 2.5 microns of platinum. All gaskets are Viton GF (peroxide grade), and the cell membranes are DuPont Nation 324. Flow through the cells is in parallel using manifolds with /4-inch fluid-flow inlet port orifices to provide equal flow to all cells. 

End plates and ports to be PVDF-lined ductile cast iron. Gaskets to be Viton for agent and Viton GF for energetics. Electrodes to be platinized titanium, pinhole-free, to a thickness of 5 micrometers for the anodes and 2.5 micrometers for the cathodes. 

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. 

Impedance diagram technique. The polarization cell consisted in a transparent plastic tube that was adhered to the paint surface by means of a silicone sealer. The tube contained distilled water and a 25 cm platinized titanium sheet, which was used as auxiliary electrode. Measurements were made with... 

SS = stainless steel Pt maybe platinized titanium or platinized niobium. 

Platinum, Platinum plating has found application in the production of platinized titanium, niobium, or tantalum anodes which are used as insoluble anodes in many other plating solutions (see Metalanodes). Plating solutions were often based on platinum "P" salt, which is diamminedinitroplatinum(II). A dinitroplatinite sulfate—sulfuric acid bath has been used to plate direcdy onto titanium (129). This bath contains 5 g/L of the platinum salt, pH adjusted to 2.0 with sulfuric acid. The bath is operated at 40°C at 10—100 A/m2. Other baths based on chloroplatinic acid have been used in both acid and alkaline formulations the acid bath uses 20 g/L of the platinum salt and 300 g/L hydrochloric acid at 65° C and 10—200 A/m2. The alkaline bath uses 10 g/L of the platinum salt, 60 g/L of ammonium phosphate and ammonium hydroxide to give a pH of 2.5—9.0. The alkaline bath can be plated direcdy onto nickel-base alloys acid baths require a gold strike on most metals. 

Since Bahnemann and co-workers have observed that a comparatively high amount of trapped holes are formed when partially platinized titanium dioxide particles are subjected to ultra band gap irradiation (cf. Fig. 7.6), they have chosen this system to study the dynamics of the photocatalytic oxidation of the model compounds dichloroacetate, DCA", and SCN- [7]. To explain their experimental observations these authors have used a model assuming two energetically different types of hole traps (see our detailed discussion above). 

Vorontsov A.V., Stoyanova I.V., Kozlov D.V. et al. (2000) Kinetics of the Photocatalytic Oxidation of Gaseous Acetone over Platinized Titanium Dioxide, J. Catal. 189(2), 360-369. 

The oxidation of a wide range of phenol and other biorefractory organic compounds (e.g., ethanol, aliphatic acids, naphthalene and anthraquinone sulfonic acids, aniline, nitrobenzene, etc.) on platinized titanium was also studied by Kotz et al. (Kotz et al. 1991 Stucki et al. 1991). The elimination of TOC was rather ineffective due to the leakage current for oxygen evolution, and the average EOI was about 0.05. 

Platinized titanium 8 x 1 0-6 Marine environments and potable water... 

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. 

Scott [11] compared three types of circulating particulate electrodes for copper recovery from dilute solutions (Fig. 1) spouted (circulating) beds, vortex beds, and moving beds. The beds contained 500— 700 pm spherical copper particles positioned on a stainless steel cathode feeder, and a platinized titanium anode. All electrodes performed similarly in terms of copper recovery current efficiencies. Recovery was found to be more efficient at low pH and high metal concentrations. The spouted bed electrode was preferred on the basis of scaleup. 

Yen and Yao [16] used a fin-type titanium cathodic current feeder (Fig. 2) in a fluidized-bed electrode to achieve enhanced copper recovery from dilute solutions. Copper particles served as the fluidized-bed cathode and platinized titanium screens were used as the anode, where oxygen evolution occurred. The feeder with the longer fin yielded higher current densities at increasing Reynolds numbers and larger bed expansions as compared with the short fin or the planar current feeder. The increased currents were due to the increased rate of copper deposition on the fluidized particles. 

The cathode material is usually stainless steel, a nickel alloy, or titanium. Graphite, lead dioxide, platinized titanium, and DSA are some of the materials that have been used as an anode. The cells are operated at a current density of between 0.1 and 0.5 A/cm. The majority of the cells used to produce hypochlorite have the parallel-plate type of geometry [81]. 

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