This study aims to appraisal the qualification of (NALCO 23214) which is used as added substance to Cooling Water Tower in General Company for Chemical Fertilizers Industry / North Region-Baiji. Already the results which we are obtained show the corrosion rates in (C.W.) system, and measuring this substance efficiency in corrosion inhibition. The results showed the substance qualification in reduction of corrosion rates when control on the special conditions in system, so the inhibitor qualification and corrosion rate were calculated.

The preparation of azo dye derivative  from " p- amino Salicylic acid " through preparation diazonium salt from aromatic amine followed by coupling reaction with (2,2,4,4-tetrahydroxybenzophenonto) was carried out to give (salicylic acid azo 2,2,4,4  tetrahydroxybenzophenon) using Dowex in the acidic form as a catalyst. The structure of azo dye produced by this reaction was assigned on the bases of spectral data (FT-IR) and (C.H.N.) analysis and the results obtained indicated the occurrence of the coupling reaction by the novel acidic catalyst.