TOTAL ORGANIC CARBON DETERMINATION OF POLYACRYLAMIDE FROM OILFIELD PROCESSES

Polyacrylamide copolymers play an important role in enhanced oil recovery (EOR), requiring assessment of its presence at different stages of the process. However, to quantify the polymer in the produced water, some potentially interfering factors must be considered due to the macromolecule and matrix complexities.1 To achieve this, the influence of molecular weight, salinity, and one type of chemical degradation (by Fe2+/O2) on the quantification by total organic carbon (TOC) were explored in this work. Additionally, viscosity measurements were carried out to evaluate the interaction between the colloid and Fe2+, since it may lead to polymer chain scission once oxygen is in solution.1,2 Polymer degradation by ferrous ion in the presence of dissolved oxygen was observed, as confirmed by a marked change in the flow-curves. Nevertheless, after 72 hours of degradation, influences on the TOC analysis were negligible. Whereas high molecular weight polyacrylamides showed a better response to the method, the salt content did not affect the quantification. The results obtained highlight the TOC as a suitable and reliable method for the determination of polyacrylamide, showing its potential application in the analysis of real samples.