Nickel-plating bath

Many electroless coppers also have extended process Hves. Bailout, the process solution that is removed and periodically replaced by Hquid replenishment solution, must still be treated. Better waste treatment processes mean that removal of the copper from electroless copper complexes is easier. Methods have been developed to eliminate formaldehyde in wastewater, using hydrogen peroxide (qv) or other chemicals, or by electrochemical methods. Ion exchange (qv) and electro dialysis methods are available for bath life extension and waste minimi2ation of electroless nickel plating baths (see... 

Selenium and selenium compounds are also used in electroless nickel-plating baths, delayed-action blasting caps, lithium batteries, xeroradiography, cyanine- and noncyanine-type dyes, thin-film field effect transistors (FET), thin-film lasers, and fire-resistant functional fluids in aeronautics (see... 

Electrodeposition of Metals. Citric acid and its salts are used as sequestrants to control deposition rates in both electroplating and electroless plating of metals (153—171). The addition of citric acid to an electroless nickel plating bath results in a smooth, hard, nonporous metal finish. 

Fig. 12.3 Part of an anode from a nickel plating bath, showing dissolution by pitting corrosion...

Fig. 12.4 Corrosion diagram for a zinc diecasting in a nickel plating bath, pH 2-2. There are two possible cathodic reactions, hydrogen evolution (H) and nickel ion reduction (AO. The corrosion current is the sum of the partial cathode currents. Even with live entry the potential is still too high to suppress corrosion, though the rate is reduced to...

In Figure 12, LB monolayers of particles 2 on a glass substrate are shown after immersion in a nickel-plating bath for 15 and 40 sec. The metal coating of the particles is clearly recognizable. 

Tanaka, M. Kobayashi, M. Seki, T. Recovery of nickel from spent electroless nickel plating baths by solvent extraction. International Solvent Extraction Conference, Cape Town, South Africa, Mar. 17-21, 2002, 787-792. 

A. Spent Nickel Plating Bath (Hard Disk Manufacturer) - contains cobalt, nickel and zinc. 

Uses. The most important commercial use for benzonitrile is the synthesis of benzoguanamine, which is a derivative of melamine and is used in protective coatings and molding resins (see Amino RESINS Cyanamides). Other uses for benzonitrile are as an additive in nickel-plating baths, for separating naphthalene and alkylnaphthalenes from nonaromatics by azeotropic distillation (qv), as a jet-fuel additive, in cotton bleaching baths, as a drying additive for acrylic fibers, and in the removal of titanium tetrachloride and vanadium oxychloride from silicon tetrachloride. 

Nickel plating baths based on electroless deposition contain a reducing agent and a catalyst. The reducing agent acts as electron donor for the reduction of metal ions to the metal. Hypophosphite, formaldehyde, hydrazine, and boron hydride are suited for this. A colloidal Pd/Sn2+ solution usually serves as the catalyst. This solution is adsorbed to the material surface and catalyzes the deposition of a monolayer of the respective metal. Further plating occurs autocatalytically with the formation of hydride ions. 

Organic acids are usually separated by means of ion-exclusion chromatography and detected via their electrical conductivity. Applications are mainly in the field of copper and electroless nickel plating baths. 

Fig. 8-45. Determination of 2-imidazolidinthione in an electroless nickel plating bath. - Separator column IonPac NS1 eluent acetic acid/methanol/ water (1 5 94 v/v/v) flow rate 0.8 mL/min detection UV (254 nm) injection 50 pL sample with 3 ppm of the relevant substance.

Electrolytic technology (meto-nitrobenzoic acid in nickel plating baths). 

T. Tsuru, D. Zhou and M. Matsumura, Recovery of spent electroless nickel plating bath by electrodialysis, J. Membr. Sci., 1999, 157, 241... 

H. Kikuchi, S. Oka and C. Nakatsuka, Continuous regeneration method of electroless nickel plating bath, Jpn. Pat. JP 63-41983 (examined application) S. Izumi, S. Fujita, Y. Taniguchi and H. Kikuchi, Reliability of print circuit prepared by copper electroless plating, Denshi Zairyou (Electric Parts Mater.), 1986, 25, 27. 

Fig. 28. Determination of interfering nitrates in a nickel-plating bath. Leading (L) and terminating (T) anions chloride and glutamate, resp. Other components of the bath, namely hypophosphite (hypo P-ite), phosphite, (P-ite), phosphate (P-ate), and lactate (Lac) are also separated...

Application of ion-selective electrodes to determine copper by standard addition method in nickel plating bath was suggested by Frant. Later Hulanicki et al." using a copper ion-selective electrode proposed a method based on multiple standard addition in presence of a copper complexing agent to prevent a harmful influence of chloride ions. In this work a similar method is used to determine copper also in zinc and cobalt baths. 

Equation (17) enables the fast and direct determination of copper in the concentration range 10 - 10" M, in the presence of up to 3 M chlorides. The method described was successfully applied to the determination of copper in nickel plating baths and also proved to be a competitive method to the routinely used spectrophotometric one. ... 

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