Izvestiya of Saratov University.
ISSN 1816-9775 (Print)
ISSN 2541-8971 (Online)


IR-spectroscopy

Thermal transformation of drilling sludge: Structural and surface changes

The study investigates the structural and surface changes occurring in carbonate drilling sludge (CDS) of oil-based origin under high-temperature pyrolysis. The main focus is placed on the transformation of the organo-mineral system using IR spectroscopy, as well as on the changes in textural characteristics analyzed by adsorption–pore methods (BET and BJH). It has been established that pyrolysis ensures the complete removal of the organic fraction of the sludge, which is confi rmed by the disappearance of characteristic aliphatic hydrocarbon bands in the IR-spectra.

Optimization of Cultivation Conditions of Azotobacter Vinelandii D-08 to Increase the Yield of Exopolysaccharide

In current research the optimization of culture conditions Azotobacter vinelandii D-08 on nutrient mediums with different content of molasses – 20, 30, 40 and 50% (by weight) was conducted. It is established that the maximum accumulation of polysaccharides was 13,78 g/l and it was observed at growth of the strain on the medium containing 50% molasses for 72 hours. The results of the method of gel permeation chromatography showed that the obtained polysaccharide has a molecular weight of 0.93532 kDa and 312.5014 kDa.