J. M. Davidson, D. Glass
Jun 9, 2007
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Influential Citations
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Journal
Industrial & Engineering Chemistry Research
Abstract
Basic carbonates of nickel (Ni(CO3)x(OH)y·zH2O, abbreviated hereafter as NBC) are uniquely reactive in absorption with reaction of dilute hydrogen sulfide (H2S) in nitrogen gas (N2). The rate is fast at ambient temperature and the very high conversion is unusual, by comparison with other oxide and carbonate absorbents. Precipitated basic carbonates are amorphous but can be prepared in quite narrow composition ranges via partial precipitation in a narrow pH range. At the lowest pH (typically 5.4) and in a system saturated by CO2 at 1 atm, the CO32-:Ni(II) ratio is x ≈ 0.75 (LpH-NBC chosen for detailed study). At pH ∼11, with ambient CO2 level, the ratio is x ≈ 0.33. These solids are unstable in the atmosphere and undergo hydrolysis or carbonation, respectively. The sulfiding reactions have variable induction periods, after which the rate accelerates to a maximum (nucleation kinetics) at a Ni(II) conversion that is frequently in the range of 0.4−0.5. The maximum rate, its crest time and the conversion (Xm,N...