The problem?
A deposit is an accumulation of substances or particles that can come from various sources, such as the precipitation of insoluble chemical components, the aggregation of suspended particles, corrosion, or contamination by foreign matter.
The customer called on FILAB, a laboratory specializing in material characterization and chemical analysis, to determine the nature of a deposit found at the bottom of an autoclave tank. The customer wanted to ensure the integrity of its equipment so as not to affect its performance.
Initial analysis performed by SEM-EDX
SEM-FEG observations and EDX analysis provided the following information. The deposit found in the tank is mainly composed of carbon (C), oxygen (O), calcium (Ca), and sodium (Na), with smaller amounts of magnesium (Mg) and silicon (Si), as well as traces of nitrogen (N), sulfur (S), chlorine (Cl), iron (Fe), and copper (Cu).
Additional analysis using FTIR
With FTIR analysis, the characteristic absorption bands observed are as follows:
- A broad band around 1403 cm-1 characteristic of the elongation vibration mode of carbonate bonds;
- Two narrow peaks around 871 and 712 cm-1 characteristic of the deformation vibration mode of carbonate bonds.
Based on these results, the spectrum of the observed deposit appears to correspond to the spectrum of a reference compound of the calcium carbonate type.
The results obtained...
The analysis carried out for this study revealed that the samples analyzed mainly contain carbon, oxygen, and calcium. Based on this elemental composition, the identification hypothesis concluded that calcium carbonate was present in the deposits analyzed.
Conclusion of the study
The discovery of calcium carbonate as the main component of the deposit analyzed provided our client with valuable insight into the origin of the blockages in their equipment. This analysis led to the development of a preventive maintenance program specifically tailored to counteract the effects of carbonate deposits, thereby improving equipment performance and durability.
