Sodium orthovanadate was tested as a corrosion inhibitor of intermetallic Al2Cu in 1 M H3PO4. The Al2Cu – H3PO4 – Na3VO4 system was studied using the following methods: inductively coupled plasma optical emission spectrometry, scanning electron microscopy with energy dispersive x-ray spectroscopy, x-ray diffraction, electrochemical impedance spectroscopy, polarisation and open circuit potential. It was found that the corrosion rate decreased as the inhibitor concentration increased. The highest inhibition efficiency 99% was obtained when sodium orthovanadate initial concentration was equal to 100 mM, pH = 1.11, due to precipitation of a protective layer of insoluble salt, containing vanadium, phosphorus, sodium and oxygen, on the surface. At pH = 0.76 the protective layer was not formed and inhibition efficiency decreased to 76%. Selective corrosion of the intermetallic phase caused a significant increase of an electric double layer capacitance and decrease of a charge transfer resistance.

The chemical fundamentals of one variant of the chelate method of combined removal of sulfur and nitrogen oxides from flue gases were described. Special attention was paid for chemical reactions responsible for production of solid wastes. A flow sheet of the technology was presented and the operation of industrial installation of SO2, NOx and dust from combustion gases of two 29 MW, grate boilers each was described. The material balance of the process was made and the quantity of solid wastes produced during 3 weeks test of the technology was presented.