Development of an alternative setup for the estimation of microcarbon residue for heavy oil and fractions: Effects derived from air presence

A robust setup has been developed that permits determination of microcarbon residue (MCR) with high accuracy and precision, in as many as 26 petroleum materials at a time. The method requires usage of very small quantity of sample (mg). The effect of gas flow rate and sample vial size in our setup is presented. Effect of presence of small amounts of air during heating is also studied. The general belief that small amounts of oxygen during initial stages of coking increases MCR, needs further study, since sample reaction toward CO2 production is expected at priori. In our study FT-IR spectra of samples before and after heating indicates that the presence of small amounts of air may or may not increase MCR, depending upon the chemical nature of the sample. This is in contrast to the general assumption that the presence of small amounts of air tends to increase MCR residue. Heavy oil and fractions analyzed by the developed setup matched literature reported values. Preliminary findings suggest that (nC7) asphaltenes as expected, are important contributors to MCR.