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               These  results  make  methodological  adjustments  for  experiments  conducting  with

               varying rates of scan potential. Thus, for metals hydrogenation, the dependencies are

               obtained starting from the potential of zero current without cathode polarization.

                      In  the solution of sodium  sulphide  the process of  Armco  iron  passivation is

               characterized by lower currents than in sodium hydroxide solution. According to the

               anodic  polarization  deepening  the  anode  current  increases  due  to  the  sulphides

               transformation and degradation of their protective properties, indicating the formation

               of  hydrogen  sulphide  in  sulphide  containing  environments  with  different

               electrochemical properties. They can have a different impact on the hydrogen release

               process, which is very sensitive to the state of the surface which it flows.

                      The hydrogen sulphide influence on cathode and anode processes, which occur

               in chloride and acetate-containing environments on Armco iron is estimated. It was

               shown,  that  this  influence  has  a  stronger  impact  on  the  rate  of  cathode  reactions,

               which increase in 2.7 ... 6.0 times. The formation of pyrite, troilite and kansite on

               Armco iron increases the volume of allocated hydrogen due to cathode polarization.

               Sulphides,  with  the  exception  of  pyrite,  reduce  cathode  overvoltage.  All  of  them


               contribute to increasing of allocated hydrogen volume, but this is not accompanied by
               symbiotic increasing process. On the basis of results analysis, it was concluded that


               sulphides  preferentially  slow  down  the  catalytic  reaction  of  hydrogen  atoms
               recombination.


                      An addition, to the generalized scheme based on literature data, the mechanism
               of  hydrogen  sulphide  influence  on  corrosion  rate  and  hydrogenation  of  steels  is


               proposed. This generalized scheme does not take into account the sparingly soluble

               sulphides as corrosion formation on steels surface. Their composition is determined

               mainly by the concentration of hydrogen sulphide in the media. On the basis of the

               results  obtained  in  the  work,  this  scheme  is  expanded  by  taken  into  account  the

               reactions  on  the  steels  surface  of  iron  sulphides  (pyrite,  troilite  and  kansite)

               formation. These iron sulphides influence on the hydrogen over-voltage and the rate

               of hydrogen atoms recombination reactions, which is a prerequisite for the absorption

               of hydrogen by metals.
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