SYSTEMATIC DESIGN OF CHEMICAL OSCILLATORS .62. THE MINIMAL PERMANGANATE OSCILLATOR AND SOME DERIVATIVES - OSCILLATORY OXIDATION OF S2O32-, SO32-, AND S2- BY PERMANGANATE IN A CSTR

Oscillatory behavior is reported in the permanganate oxidation of several species in the presence of KH2PO4 in a stirred tank reactor. With Mn2+ as the reductant and NaOH added to maintain the proper pH, the resulting system is the “minimal permanganate oscillator,” which serves as a core from which other oscillating permanganate reactions can be generated. In one example, discussed in detail, the manganous ion and NaOH are replaced by thiosulfate ion and H2SO4, respectively. Other permanganate oscillators contain sulfite or sulfide ions as the reductant. The phosphate serves both as a stabilizer of soluble Mn(IV) and as a pH buffer. © 1990, American Chemical Society. All rights reserved.