TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The metal chelate comprises a polyvalent metal chelatable in both oxidized and reduced states. The polyvalent metal is tin, lead, copper, manganese, platinum, tungsten, nickel, palladium, chromium, cobalt, vanadium, titanium, tantalum, zirconium and molybdenum. The carboxylic acid metal chelate is a transition metal chelate of iron (solution of sulfates, nitrates, thiosulfates, chlorides, acetates, oxalates or phosphates). The transition metal salt is chelated with a carboxylic acid (succinic acid, citric acid, malic acid, gluconic acid or oxalic acid). The solution is maintained at a pH of 7-9 using a hydroxide of an alkaline earth element (Na, K or Mg). The oxygen source is air or molecular oxygen.Preferred Process: The process for recovery of elemental sulfur is a continuous stirred reactor process, bubble column reactor process, airlift type reactor process or a batch process. The concentration of the chelating agent is 500-20000 ppm. The sour/natural gas is contacted with the metal chelate solution at ambient temperature and atmospheric pressure. EXAMPLE - Water (500 ml) was placed in a container with ferric nitrate (10 g). On total dissolution of salt, 31.01 mol of gluconic acid solution was added. 10 % extra acid was added for complete and proper chelation of metal salt. The pH of the solution was checked and 5N NaOH solution was added to maintain the pH 7.0 - 9.0. The forgoing was mixed at RT and atmospheric pressure to form the solution. The H2S gas was then slowly bubbled through the solution at constant flow rate. While the test contents began initially as a true solution, the solution soon became dark in color, showing slurry of precipitated sulfur. The feed gas was continued to pass through the solution until no more precipitation of sulfur was observed. This was readily tested by passing the outlet gas through a tube containing AgNO3 solution which began to turn black. The H2S gas was passed for 10 more minutes so as to ensure complete conversion of H2S to elemental sulfur. While conversion of H2S to elemental sulfur occurred, the Fe (III) simultaneously became reduced to Fe(II) so as to reoxidize Fe(II) to Fe(III) excess air or oxygen was sparged through the solution. On oxidation of chelated solution, the color of the precipitated sulfur turned to off-white. Total sulfur recovery on completion of the process was 90 mg or 99 % purity.