Abstract
A solid-state heterogeneous membrane electrode that is selective to sulfate ions was prepared from a poly(vinyl chloride) membrane impregnated with barium chloranilate. Although the electrode response was under Nernstian (16mV/pSO42-) it was applicable to a sulfate concentration range of 10-1.5 to 10-4mol dm-3. The preferable pH range was 6-11 and the response time was about 30s. Sulfate ions in organic compounds and polymers can be assayed with this electrode without serious errors at low concentrations of various interfering anions. The electrode remained active
for at least 300 measurements, or 3 months.