H2SO Systems

Figure 3. Proposed mechanism for methane oxidation by the Pt(bpym)CI2/H2SO system.

Fig. 2.12. Dependence of the temperatures of transition from the isotropic to the anisotropic state in the PBA-H2SO system on the concentration of polymer based on data from optical polarization measurements ( ) and differential thermal analysis (O) [36].

Fig. 2.18. Dependence of the critical temperatures of light scattering (tuibidity) in the PPTA-H2SO system on the concentration of polymer [46].

Nitrating system, h2so4/ % Temp./ °C Isomer proportions/ % Rate constants Aa/1 mol 1 s 1 h2so. / % Arrhenius parameters ... 

The rate changes should reflect a change In the concentration and stability of the cationic Intermediates In the acid. In all cases the acidity of modified H2SO/ decreases as the additive concentration Is Increased, typical relationships being shown In Figure 4. The change In acidity must be reflected In the steady state R concentration which therefore always decreases In these systems. 

Figure 18 Composition changes in the H2SO.1 + (NH4)2SO-i + H2O system during the various stages of the proposed process.

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