Nanocap-shaped tin phthalocyanines: synthesis, characterization, and corrosion inhibition activity.
Thermal and microwave reactions between [PcSn(IV)Cl2] (1) and the potassium salts of eight fatty acids (2 a-h) led to cis-[(RCO2)2Sn(IV)Pc] compounds (3 a-h) in yields ranging from 54 to 90 %. Compounds 3 a-h were fully characterized by elemental analysis, spectroscopy (IR, UV/Vis, multinuclear NMR), and seven X-ray diffraction structures, whereby two different allotropes were observed in two cases. The two carboxylates in 3 have a cis anisobidentate binding mode, octacoordination of the tin atoms with square-antiprismatic geometry, and pi-electron-rich nanocap shapes. On account of the latter characteristics, 3 a-h compounds have anticorrosion properties. LPR and Tafel electrochemical methods were used to characterize the behavior of these derivatives in naturally aerated sour brine, which is a common environment in petroleum production and refinery operations. The measurement of the corrosion rate of carbon steel AISI 1018 in the presence of 3 a-h (500 ppm) gave efficiencies of 61-87 % for the inhibitor performance. Of the different derivatives examined, compounds 3 e and 3 h were the most effective corrosion inhibitor prototypes.
Beltrán
Hiram I
HI
PIM-IMP, Eje Central Lázaro Cárdenas 152, Col. San Bartolo Atepehuacan, C. P. 07730 Mexico D. F., Mexico. hbeltran@imp.mx
Esquivel
Raquel
R
Lozada-Cassou
Marcelo
M
Dominguez-Aguilar
Marco A
MA
Sosa-Sánchez
Arturo
A
Sosa-Sánchez
Jose L
JL
Höpfl
Herbert
H
Barba
Victor
V
Luna-García
Rolando
R
Farfán
Norberto
N
Zamudio-Rivera
Luis S
LS