CHEMICAL KINETICS OF HYDROGEN SULFIDE SELECTIVE OXIDATION IN IRON CHELATE SOLUTIONS

Tsapekis, OG; Salmas, CE; Androutsopoulos, GP

dc.contributor.author	Tsapekis, OG	en
dc.contributor.author	Salmas, CE	en
dc.contributor.author	Androutsopoulos, GP	en
dc.date.accessioned	2014-03-01T01:57:19Z
dc.date.available	2014-03-01T01:57:19Z
dc.date.issued	2008	en
dc.identifier.issn	1790-7632	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/28401
dc.subject	hydrogen sulfide	en
dc.subject	selective oxidation	en
dc.subject	iron chelate	en
dc.subject	absorption with chemical reaction	en
dc.subject	NTA	en
dc.subject	nitrilo triacetic acid	en
dc.subject.classification	Environmental Sciences	en
dc.subject.other	CHEMISTRY	en
dc.title	CHEMICAL KINETICS OF HYDROGEN SULFIDE SELECTIVE OXIDATION IN IRON CHELATE SOLUTIONS	en
heal.type	journalArticle	en
heal.language	English	en
heal.publicationDate	2008	en
heal.abstract	The present work concerns the investigation of the chemical kinetics of H2S selective oxidation into elemental sulfur, by gas absorption and chemical reaction in Fe3+ center dot(NTA) aqueous solutions. By using initial reactivity data, priority is given to the study of intrinsic kinetics i.e. to avoid interactions with ligand degradation and the presence of sulfur. A wetted wall gas-liquid reactor was employed under a batch-recycle regime. The conversion of Fe3+ to Fe2+ chelate was determined over the pH range ca. 3-6, temperature range ca. 30-60 degrees C and a short overall per run contact time of phases. The penetration theory was used for the evaluation of intrinsic reaction rate constant and enhancement factor. Activation energy values determined from the pertinent Arrhenius plots fall in the range, Ea=17.2- 22.8 kcal mol(-1). These values compare satisfactorily with the value Ea=24 kcal mol-1 obtained from a similar kinetic study performed in a bubble column reactor and indicates a chemical reaction control of the overall gas absorption phenomenon. Enhancement factors varied in the respective ranges E =2.7-7.5 (pH=3), E=3.2-14.1 (pH=4), E=5.9-17.0 (pH=5), Kai E=6.7-20.1 (pH=6) indicating a substantial increase of the mass transfer coefficient due to chemical reaction. For the experimental conditions applied in this study the following kinetic correlation was validated: R-H2S = {[-10.62 + 4.15 (pH)].10(14) exp (-19083/RgT)} C-H2S	en
heal.publisher	GLOBAL NETWORK ENVIRONMENTAL SCIENCE & TECHNOLOGY	en
heal.journalName	GLOBAL NEST JOURNAL	en
dc.identifier.isi	ISI:000260710100012	en
dc.identifier.volume	10	en
dc.identifier.issue	3	en
dc.identifier.spage	386	en
dc.identifier.epage	394	en