No abstract

Buffer capacity analysis of open atmospheric gas-liquid systems containing main acidic and basic atmospheric pollutants was carried out. Usually the buffer capacity is considered as a function of pH as an independent variable. In this work the buffer capacity is analysed including the dependence of pH on the composition of a system. Such an approach allows finding an important, from the viewpoint of atmospheric water acidification, relationship between the gas phase composition and the buffer capacity. It was found that buffer capacity of the open gas-liquid systems may be very high and it may cause the liquid phase pH to remain at low levels. The buffer capacity of the analysed systems is most strongly affected by the simultaneous presence of ammonia and strong acids in the gas phase. The higher concentrations of strong acid gases the lower NH 3 concentration is sufficient to achieve high buffer capacity. In the presence of strong acid gases, calcium ions affect both the buffer capacity and the liquid phase pH only at low NH 3 concentrations. High buffer capacity of open gas-liquid systems may be one of the reasons why the reduction in emissions of acidic gas pollutants has little effect on decrease in atmospheric water acidity.