The diffractogram of corrosion products obtained after 96 h of exposure (Figure 7) shows peaks at approximately 18[degrees], 30[degrees], 35[degrees], 38[degrees], 50[degrees], and 54[degrees] which are the same as those of mackinawite
(M), that is, a tetragonal crystalline form of iron sulfide .
Abdel-Wahab, "Sorption of selenium(IV) and selenium(VI) to mackinawite
(FeS): effect of contact time, extent of removal, sorption envelopes," Journal of Hazardous Materials, vol.
Pyrite formation in nature requires two processes: (1) [Fe.sup.2+] first forms mackinawite
in Fe-rich solutions ([Fe.sup.2+.sub.aq] + [H.sub.2][S.sub.aq]/H[S.sub.aq.sup.-] [right arrow] FeS); (2) mackinawite
then dissolves and forms pyrite (FeS + [S.sup.2-.sub.n]/[H.sub.2]S [right arrow] Fe[S.sub.2]).
Equilibrium expressions related to the solubility of the sour corrosion product mackinawite
Ehrhardt, "Surface chemistry and structural properties of mackinawite
prepared by reaction of sulfide ions with metallic iron," Geochimica et Cosmochimica Acta, vol.
Modification of Mackinawite
with L-Cysteine: Synthesis, Characterization, and Implications to Mercury Immobilization in Sediment.
En presencia de BSR, se forma una pelicula superficial no protectora de sulfuro de hierro (mackinawite
) y se forman una cantidad importante de picaduras en toda la superficie del metal.
When exposed to sulphur species in bio-environments, iron and steel first develop a poorly protective film of mackinawite
(an iron sulfide rich in iron) that changes later, to a more stable iron sulfides through different chemical and electrochemical paths.
Corrosion rate of mild steel at extremely low [H.sub.2]S controls the corrosion rate even when present in minute amounts, [H.sub.2]S reduces the pure C[O.sub.2] ([H.sub.2]S-free) corrosion rate by 3-10 times due to formation of a thin mackinawite
Lennie AR, Redfern SAT, Champness PE, Stoddart CP, Schofield PF, Vanghan DJ (1997) Transformation of mackinawite
to greigite: An in-situ -ray powder diffraction and transmission electron microscope study.
[5, 6], the interaction of Fe with [H.sub.2]S in aqueous environments proceeds toward the formation of mackinawite
through the reaction paths shown in Figure 2.
Charnock et al., "Uranium uptake from aqueous solution by interaction with goethite, lepidocrocite, muscovite, and Mackinawite
: an x-ray absorption spectroscopy study," Environmental Science and Technology, vol.