Optical in-situ measurements and modeling of post-flame sulfation of NaOH(g) and NaCl(g)

Post-flame sulfation of gaseous sodium hydroxide (NaOH) and chloride (NaCl) was investigated with optical in situ measurements at 850 to 1475 °C. A multi-jet burner used generate well-controlled combustion environments. The also enabled the separate feeding species SO2 environment where reactions occurred. Concentrations NaOH(g) NaCl(g) were measured product gas using broadband UV absorption spectroscopy follow degree sulfation. At 1275 °C almost no occurred an initial concentration 20 ppm concentrations between 0 150 ppm. 985 °C, decreased less than 5 above 50 all sulfated under these conditions. experimental results for gas-phase NaOH compared previous KOH same conditions shown be similar Sulfation generally a more significant extent NaCl(g). 1115 observed. lowest temperature, from 12 after addition SO2. Chemical equilibrium calculations kinetic modeling updated model detailed Na-Cl-S chemistry results. Above 1100 system can described by chemical equilibrium, implying that is reached 100 ms. temperatures below indicated control. Under conditions, good agreement but over-predicted combined data, present study support alkali occur phase through homogeneous reactions.