This study assessed V5+ concentration and V5+ to V4+ ratio effects on the H2S absorption and oxidation to elemental sulfur from H2S gas streams in simulated Stretford solutions. Laboratory-derived sulfur products were characterized by inductively coupled plasma optical emission spectrometry, X-ray diffraction (XRD), particle size distribution (PSD), and differential scanning calorimeter (DSC) analyses for probing the chemical, mineralogical, and physical properties of the sulfur products. H2S absorption and sulfur production efficiencies increase with an increase in the V5+ concentration. However, the sulfur's PSD results are finer and the purity decreases as the V5+ concentration increases because of K/Al/Si/Mg/Fe impurities in the added technical grade sodium ammonium vanadate (SAV) to the Stretford solution. XRD and DSC results of the orthorhombic sulfur (alpha-S-8) products indicate that these products have similar mineralogical properties and melting points compared to those of the commercial alpha-S-8. V5+ to V4+ ratios decreased with a decrease in alpha-S-8 production efficiency, and a total vanadium loss of 89% was achieved because of the V4+ precipitation from the Stretford solution without disodium salt of 2,6 and 2,7 isomers of anthraquinone-disulphonic acid (Na-2 [ADA]). Low V5+ to V4+ ratios were found to be responsible for the sulfur sol formation and subsequent dark-colloidal V4+ and fine alpha-S-8 precipitation in the Stretford units. The Stretford process must be operated with Na-2[ADA] for the V4+ oxidation in the solutions. Research outcomes as well as the total replacement for SAV with a pure V5+ salt can assist the Stretford operators to further improve alpha-S-8 quality and its production efficiency.