Oxidation of barbituric and thiobarbituric acids by chromium trioxide in different acidic media: A kinetic and mechanistic aspects

摘要: Abstract Kinetics and mechanism of oxidation two biologically reactive heterocyclic compounds, namely, barbituric (BA) thiobarbituric (TBA) acids by chromium trioxide (CrVI) have been explored using UV–Vis absorption spectra in sulfuric perchloric acid solutions at fixed ionic strength 2.0 mol dm−3 a temperature 298 K. The reactions demonstrated 3:4 stoichiometry (organic acid: CrVI). kinetics the examined acidic media were set to be first order with admiration [CrVI] fractional orders organic H+ concentrations. Varying strengths dielectric constants reaction had no noteworthy influence on reactions’ rates. Tests for free radicals involvement throughout positive. Addition chromium(III) as predicted product did not considerably alter rates whereas addition manganese(II) diminished Supplementation some divalent transition metal ions increased At same investigational circumstance, BA both about 20–30% higher than those TBA, acquired also found TBA almost percentages. products described 2,4,5,6-pyrimidinetetraone (alloxan) 2-thio-4,5,6-pyrimidinetrione, respectively. A conceivable has anticipated. derived rate-law expression was good agreement outcomes. activation parameters regard second rate assessed debated. existing study presents an unprecedented simple inexpensive treatment method removal certain pollutants saving environment human health.