ON SATURATION OF MAGNESIAN CORDIERITE WITH ALKANES AT HIGH TEMPERATURES AND PRESSURES

Abstract

Incorporation of hydrocarbons (CH4, C2H6, C3H8, C4H10) in cordierite channels was experimentally studied at 700 °C and at pressures from 200 to 1000 MPa, (avoiding recrystallization). The maximum concentrations of hydrocarbons determined by gas chromatographic analysis are CH4=78.3, C2H6=134, C2H4 + C2H6=26, C3H8=28, C4H10=32, C5H12=23, and C6H14=7 × 10−3 wt%). According to IR spectroscopy data, the channel forms of hydrocarbons differ from the forms on the surface. As a result of interactions with the framework oxygen, normal hydrocarbons are converted to saturated oligomers and their fragments. Small amounts of water molecules of the first and second types (up to 0.3 wt%) are formed in the same way. As pressure grows from 200 to 1000 MPa, the total content of structural hydrocarbons is nearly doubled. Special runs on cordierite saturation in mixtures of hydrocarbons with water showed that low contents of hydrocarbons in natural cordierites correspond to their large concentrations in fluid.