The authors wish to make the following corrections to this paper : We worked at a temperature of 60◦C for all the tests carried out in which FeS2 was added as a reducing agent, whereas in the other experiments, other added Fe reducing agents were worked at room temperature (25 ◦C). This aﬀects the results presented in Table 5 (results when working with FeS2), Figures 4a and 6a. By accident and through carelessness, we did not indicate this important detail in the work methodology. For this reason, we must correct it for the readers, otherwise the reproduction of the results of our experiments will not be possible due to incorrect working parameters. However, we conﬁrm that this error does not aﬀect the conclusions of the manuscript. We must indicate that it is unlikely that the following series of reactions that were presented in the document could occur at room temperature: 3FeS2 + 4H2SO4 = 3FeSO4 + 4H2O + 7S (1) 6FeSO4 + 4H2SO2 = 3Fe2(SO4)3 + 4H2O + S (2) 2FeS2 + 4H2SO4 = Fe2(SO4)3 + 4H2O + 5S (3) 15MnO2 + 2FeS2 + 14H2SO4 = Fe2(SO4)3 + 15MnSO4 + 14H2O (4) We will update the article and the original version will remain available on the article webpage.