Nickel carbonyl, sampling

C05-0141. Many of the transition metals form complexes with CO these complexes are called metal carbonyls and have the general formula M (CO). A 0.500-g sample of gaseous nickel carbonyl in a 0.100-L bulb generates a pressure of 552 torr at 30 °C. What is the formula of nickel carbonyl ... 

Two final examples of the sensitivity and general applicability of the FTIR gas analysis technique are illustrated in Fig. 8. Trace (A) shows the spectrum obtained from an ultra-air filled 70 liter sampling bag into which had been injected, 18 hours previously, 4.8 microliters of TDI, toluene diisocyanate. On the basis of the single feature at 2273 cm l, it is estimated that 50 ppb TDI could be detected. The lower Trace (B), shows the spectrum of nickel carbonyl. This highly toxic but unstable gas was found to decay rapidly at ppm concentrations in ultra air (50% lifetime 15 minutes). Calibration of its spectrum was established by recording successive spectra at ten minute intervals and by attributing the increase in carbon monoxide concentration (calibration known) to an equivalent but four times slower decrease in nickel carbonyl concentration. The spectrum shown represents 0.6 ppm of the material. Note the extraordinary absorption strength. The detection limit is thus less than 10 ppb. 

If these catalysts are heated to 80° C. in a stream of CO, nickel is removed from the carrier as nickel carbonyl that volatilizes out of the heated sample (7). The amount of nickel eliminated can be determined by heating the gas stream after it has passed the catalyst sample. A nickel mirror is then deposited on the wall of the reaction vessel and can be weighed. After one day about 90-95 % of the nickel proves to be removed. The remaining residues have surface areas (Fr) that still are related to the original Ni content... 

U.S. Department of Labor, Occupational Safety and Health Administration (OSHA). 2004. Chemical sampling information Nickel carbonyl. Washington, D.C. OSHA. 

D. J. C. Yates (Esso Research Co., Linden, N. J. 07036) It is interesting that you find the same migration effect of nickel on NaX zeolites that I found some time ago on samples reduced under milder conditions than you used. Did you find less migration with nickel on Zeolon I am also concerned with the use of CO for area measurement with nickel, as it is easy to make nickel carbonyl with reduced nickel even at quite low CO pressures. Did you check your results with hydrogen chemisorption ... 

The gas phase reaction proceeds very much as described for nickel carbonyl, but the product does not contain the nitrite group (10). A smoke is formed immediately the gases come into contact, but the analysis and infrared spectrum of the solid formed show it to be the oxide-nitrate Fe0(N03). It seems likely that initial reaction involves the NO2 radical, and an iron nitrite such as Fe(N02)3 may be produced initially. The oxidation-reduction properties of the ferric and nitrite ions may render them incompatible Fe0(N03) would then be left as a decomposition product. So little is known about transition metal nitrites that this must remain conjecture at present, but it may be relevant to recall that it has not yet been possible to isolate pure samples of Fe(N03)3, A1(N03)3, or Cr(N03)3. 

XPS Spectrum of Surface. Figure 2 shows XPS spectra of CDC nickel-plated sheets with various pretreatment. Carbon, oxygen, chromium and nickel are observed in the surface of CDC nickel-plated sheets oiled with DOS and ATBC. The carbon spectra show ester carbonyl carbon and hydrocarbon species on both samples. The ester carbonyl carbon reflects the ester bond of DOS (C8Hi7C00C8Hi60C0C8Hi7) and ATBC ((C3H7COO)3C(CH2)OCOCH3). 

With plahnum and palladium catalysts, supported on siUca, alumina and active carbon, both H2, O2 and CO probe molecules are available for dispersion measurements. For rhodium, the various values are taken from the work of Ferretti et al. [102]. For ruthenium and iridium, O2 cannot be used as a probe molecule for dispersion measurements, because there is formahon of bulk oxides. With nickel, only H2 gives reUable results, O2 and CO cannot be used as probe molecules for dispersion measurements, because there is formation of bulk oxides with O2 and metal-carbonyls with CO, but the dispersion of the sample can be additionally measured by magnetic measurements. 

After microwave-assisted digestion of the sample with a mixture of nitric acid and hydrogen peroxide, during which equilibration with the isotopically enriched spikes added also took place, formic acid was used to convert the isotope-diluted elements into volatile compounds in a photo-reactor. In the case of iron and nickel, the corresponding volatile carbonyl compounds are most likely formed, whereas in the case of selenium, hydride compounds are obtained. A schematic representation of the UV-PVG-ICP-IDMS setup is shown in Figure 8.10. The good accuracy of results was demonstrated by the successful analysis of certified reference materials. Extremely low LODs of 0.18, 1.0, and 1.7 pgg were found for Ni, Fe, and Se, respectively, which are improvements of a factor of 30 for the two metals and 150 for Se compared with conventional pneumatic solution nebulization. 

Thus, as is the case for the st pincer derivatives with nickel, Moulton and Shaw also reported the first PCP pincer rhodium and iridium derivatives and studied their reactivity toward carbon monoxide [4]. Hence, the (PCP) rhodium derivative (38) affords complex (40), as a product of the decomposition of the unstable hydrido chloro carbonyl intermediate (39) via a hydrodechlorination process, although this compound is obtained impure. To favor the hydrodechlorination process, an alternative route was attempted employing EtONa as base. This approach afforded exclusively compound (40) (Scheme 2.21). It is noteworthy that analogous reactions with the iridium analogous to complex (38) only afford impure samples of the carbonyl species analogous to complex (40). 

Park, C. J., and Yim, S. A. (1999). Determination of nickel in water samples by isotope dilution inductively coupled plasma mass spectrometry with sample introduction by carbonyl vapor generotion.J. Anal. At. Spectrom. 14(7), 1061. 

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