Neutral reagents are easier to dispose of nowadays and do not attack the underlying material.

When inorganic mineral acids are used for derouging, waste water disposal is an important factor and involves considerable expenditure, depending on the prevailing circumstances. In addition, when acid solutions are employed, an attack on the underlying material cannot always be ruled out, at least on a microscopic scale. Research was therefore conducted into neutral reagents which are much easier to dispose of and do not attack the underlying material even when the specified temperature is exceeded or very long action times allowed, not even at the microscopic level. We therefore had to develop chemical substances which are able to reduce iron oxides and hold the iron ions from the oxides in solution in an appropriate way; for this purpose, a reduction agent and a complex former are needed. From these considerations, various chemical combinations can be derived which either reduce the iron oxides or have a complexing effect on iron ions. Suitable combinations of active substances have now been developed which permit both a reduction of the iron oxides and complexing of the iron ions without the need for N2 superimposition. Very good derouging results can be achieved in this way, but depending on the extent of the rouging coating a reaction temperature of between 60 and 80°C is needed. We are therefore able to offer you highly efficient, pH-neutral derouging to suit your particular application.