Cadmium borates

CdO is used in connection with the stabilization of poly(vinyl chloride). This is discussed below in more detail. It also finds application in modifying the thermal properties of teflon and some rubbers. CdS is used in some smoke detectors, in lasers and in phosphors. The cadmium(II) halides are important as catalysts and are also used in pyrotechnics. Cadmium borates of the general type (Cd0)x(B203), are also used as phosphors. CdS04 is employed in the Weston cell, which is important as a voltage standard.137... 

Rabinovich D (2006) Poly(mercaptoimidazolyl)borate Complexes of Cadmium and Mercury 120 143-162... 

The most efficient system devised by Monsanto uses electrodes fabricated from carbon steel plate, electro-coated on one face with cadmium. These are stacked in parallel so that the electrolyte can be pumped through the gap between successive plates. Overall tire system forms a series of electrochemical cells with a cadmium cathode and a carbon steel anode. Each plate of metal forms the cathode of one cell and the anode of the next in the stack. Electric current is passed across the stack. The electrolyte contains phosphate and borate salts as corrosion inhibitors, EDTA to chelate any cadmium and iron ions generated by corrosion together with hex-amethylenebis(ethyldibutylammonium) phosphate to provide the necessary telraal-kylammonium ions. This electrolyte circulates through the cell from a reservoir and there is provision for the introduction of acjylonitrile and water as feedstock. The overall cell reaction is ... 

Lopez Garcia et al. [2] have described a rapid and sensitive spectrophotometric method for the determination of boron complex anions in plant extracts and waters which is based on the formation of a blue complex at pH 1 - 2 between the anionic complex of boric acid with 2,6-dihydroxybenzoic acid and crystal violet. The colour is stabilised with polyvinyl alcohol. At 600 nm the calibration graph is linear in the range 0.3-4.5 xg boron per 25 ml of final solution, with a relative standard deviation of 2.6% for xg/l of boron. In this procedure to determine borate in plant tissues, the dried tissue is treated with calcium hydroxide, then ashed at 400 °C. The ash is digested with 1N sulfuric acid and heated to 80 °C, neutralized with cadmium hydroxide and then treated with acidic 2,6-dihydroxybenzoic acid and crystal violet, and the colour evaluated spectrophotometrically at 600 nm. Most of the ions present in natural waters or plant extracts do not interfere in the determination of boron complex anions by this procedure. Recoveries of boron from water samples and plant extracts were in the range of 97 -102%. 

Instability constants for the formation of Al(BO )s, AlBO +, and Al(B02)i have been evaluated (374), although the reliability of the results is in question. Other metals that have been examined in borate solutions include lead (372), cobalt (270, 371), zinc, and cadmium (369), providing evidence for Pb(B02>3, PbB02, CoIBOa) , NilBO s, ZnlBO, and Cd(BO )S . Silver is believed to form a weak neutral complex AgB02 (177). 

Only a few borates of cadmium are known. Cadmium monoborate monohydrate CdO B203 H20 is formed in cadmium nitrate/borax solutions. The 1 2 5 borate precipitates from hot boric acid solutions containing cadmium acetate (206). Its dehydration occurs in three stages, with one water molecule lost at 100°C, three at 100-150°C, and the last at over 300°C. 

Amorphous products were obtained in the reaction between alkali metal borates and cadmium chloride, analyzed as the 2 3 7 compound (337). More recently, a patent claiming the formation of 6CdO 7B203 (3-3.8)H20 has appeared (264). 

Chelating agents such as triethanolamine borate also behave as latent catalysts at elevated temperatures. Other boron-containing compounds, cadmium or zinc bromide dieth-ylenetriamine, and salts of aluminum acetoacetic ester have also been suggested as curing agents for high-temperature epoxy adhesives. 

SYNS BORATE(l-),TETRAFLUORO-, CADMIUM (2 1) (9CI) CADMIUM FLUOROBORATE CADMIUM TETRAFLUOROBORATE (7CI) TL 1026... 

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