Stibine generator

Chen H, Brindle ID, and Zheng S (1992) Stibine generation combined with flow injection for the determination of antimony in metal samples by atomic emission spectrometry. Analyst 117 1603-1608. 

Lead—antimony or lead—arsenic ahoys must not be mixed with lead—calcium (aluminum) ahoys in the molten state. Addition of lead—calcium—aluminum ahoys to lead—antimony ahoys results in reaction of calcium or aluminum with the antimony and arsenic to form arsenides and antimonides. The dross containing the arsenides and antimonides floats to the surface of the molten lead ahoy and may generate poisonous arsine or stibine if it becomes wet. Care must be taken to prevent mixing of calcium and antimony ahoys and to ensure proper handling of drosses. 

It is reported that an aluminium cleaner containing low concentrations of hydrofluoric acid can generate stibine from antimony containing bearing-metal alloys, to the permanent detriment of the health of nearby workers. Presumably arsine could appear from arsenic containing alloys both are gases and extremely toxic. 

Sturgeon et al. [59] have described a hydride generation atomic absorption spectrometry method for the determination of antimony in seawater. The method uses formation of stibene using sodium borohydride. Stibine gas was trapped on the surface of a pyrolytic graphite coated tube at 250 °C and antimony determined by atomic absorption spectrometry. An absolute detection limit of 0.2 ng was obtained and a concentration detection limit of 0.04 pg/1 obtained for 5 ml sample volumes. 

Dernehl C, Stead FM, Nau CA Arsine, stibine and H2S Accidental generation in a metal refinery. Ind Med Surg 13 361, 1944... 

M. J. Cal-Prieto, M. Felipe-Sotelo, A. Carlosena and J. M. Andrade, Direct generation of stibine from slurries and its determination... 

Kusaka et al. [760] generated the gaseous hydrides of antimony(III), arsenic(III) and tin by sodium borohydride reduction. The hydrides were swept from solution onto a Porapak Q column where they were separated and detected at a gold gas-porous electrode by measurement of the respective electro-oxidation currents. Detection limits for 5ml samples were As(III) (0.2pg L ) Sn(II) (0.8pg L 1) Sb(III) (0.2pg L 1). The order of elution is hydrogen, arsine, stannane, stibine and mercury, ie the order of increasing molecular weight. 

In Situ Generator. Very reactive substances such as stibine must often be generated in situ. A method for preparing stibine, reported by Gunn et al. [J. Phys. Chem., 64, 1334 (I960)], was modified to permit continuous generation at a controlled rate. 

Although the reaction is not quantitative, it was found that reproducible concentrations of stibine could be generated, even at different syringe drive delivery rates. 

Stibine is generated if nascent hydrogen can react with antimony in an acid environment, e.g. in lead-acid batteries, where antimony may be a component of the battery plates. ... 

The more troublesome problem is the biotransformation of arsenic into arsine gas. Four common soil fungi, two anaerobic bacteria, and algae in surface water can generate a methylated version of arsine. It is unknown whether these same biological processes can convert antimony to stibine. 

Direet generation of stibine from slurries and its determination by ETAAS was studied using simplex multivariate optimisation (eoneentrations of HCl and NaBH4, and Ar flow rate). Previous experimental designs were made to select those variables. 

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