TECHNOLOGY FOCUS - ELECTRICAL POWER AND ENERGY - Preferred Components: The electrolytic cell is divided in two parts, anodic compartment and cathodic compartment, by an permoselective anionic membrane, the liquid flow removed from the sulfur, in which ferrous ions and ferric ions, in g/l is between 5/1 and 12/1 and in which the oxidation reaction of the ferrous ions to ferric ions occurs, is sent to the anodic compartment, in the cathodic compartment of the cell an acid solution is sent with a concentration of preferably such as to maintain an isotonicity relative to the anions in the two compartments and in which the reduction reaction of the hydrogen ions occurs with the development of gas hydrogen accompanied with the liberation of the anions that migrates through the permoselective anionic membrane from the cathodic compartment to the anodic compartment and where the anionic membrane furthermore inhibits any countercurrent of iron ions. The electrolytic cell is unipolar or multiple bipolar (preferred) and the anodic compartments are fed in parallel or series. The anode of the electrolytic cell is bidimensional or tridimensional (flow bed or a fixed bed) and is constituted preferably of noble metals or alloys of lead, steel, carbon or graphite. The cathode, preferably bidimensional, is constituted of materials with low over voltage and resistant in highly acid conditions, preferably steel or noble metals. The permoselective anionic membrane presents values of the flow density of 200-400 A/m2. The electrolytic cell foresees a hydraulic head or a Delta P between the catholyte and anolyte. The gaseous hydrogen is developed at the cathodic compartment of the electrolytic cell with purity higher than 99.99%.    TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Process: The removal of elementary sulfur from the liquid flow is performed through an heating and a filtration system at one or more stages and subsequent washing recovering elementary sulfur with a purity up to 99.9%. The chemical absorption is performed working at room temperature and at 1-50 (preferably 1-10) bar, for the filler scrubber, the tray column and the bubble column. In the process, an apposite recycle ratio in the circulating circuits in the electrolytic cell is introduced, to permit fluid dynamic conditions of turbulent regime. The process comprises contacting in a reactor (RA), preferably in a filler scrubber, in order to realize a gas-liquid or liquid-liquid absorption with reaction, a gas or liquefied gas flow (1) containing H2S, with an acid liquid flow (2) containing ferrous and ferric ions. The flows (1) and (2) can be fed in equicurrent or countercurrent, operating preferably at room temperature and at 1-10 bars. In the exit from the scrubber head, a gas or liquefied gas flow (3), purified from H2S with residual H2S concentrations up to 1 ppm can be collected, and from the bottom a liquid flow (4) containing ferrous/ferric sulfate solution and with elementary sulfur suspended with a concentration between 1-50 g/l can be recovered; subjecting the liquid flow (4) from the scrubber to a filtration system at one or more stages and subsequent washing (sulfur separation (SS)) in which sulfur is recovered; sending the liquid flow (5), purified from sulfur from the filtration system (SS), to the anodic compartment of an electrolytic cell (CE), in which the oxidation reaction of the ferrous ions to ferric ions is carried out regenerating in this way the feed flow of (RA). In the electrolytic cell (CE) there is an entering flow from the cathodic compartment, through the selective anionic membrane, of anions that are liberated at the cathode. In the other circuit of (CE) is fed an acid solution with an acid concentration preferably such as to maintain an isotonicity relative to the anions in the two compartments and is separated from the anodic compartment by the permoselective anionic membrane, and in which the reduction reaction of the hydrogen ions occurs. Preferred Components: The gas-liquid or liquid-liquid absorption is carried out in one or more reactors comprising a filler scrubber, a tray column, a bubble column or using membrane contractors. The gas or liquefied gas flow containing H2S and the acid liquid flow containing essentially ferric ions, in total iron ion concentrations of 20-200 (preferably 100-150) g/l, and in which the ratio between the concentrations of ferrous ions and ferric ions in g/l is preferably between 1/5 and 1/12, are fed in equicurrent or in countercurrent. EXAMPLE - Flow of natural gas (100 m3/hour) contained hydrogen sulfide (H2S) (15 vol.%) was sent to a filler scrubber in countercurrent with an acid solution (815 Kg/hour), constituted of sulfuric acid (7%) and a total iron concentration (120 g/l). The weight percentage of ferrous sulfate and ferric sulfate in the acid solution sent to the scrubber were respectively 2.1-33%. The hydrogen sulfide (H2S) reacts with the ferric iron with a conversion degree (100%), obtaining in the head of the scrubber a purified gas flow in which a residual concentration of H2S (210 ppm) was obtained. From the bottom of the scrubber was collected an acid liquid flow (845.2 Kg/hour), the flow was constituted of ferrous sulfate and ferric sulfate and elementary sulfur in suspension that was separated by filtration and subsequently washed, obtaining in the exit a solid flow of elementary sulfur with a purity of 99.8%. The liquid flow, purified from the sulfur and with sulfuric acid concentrations (15%), was fed to the anodic circuit in a unipolar electrolytic cell in which the anode was of lead, the cathode was of stainless steel and the anodic circuit and the cathodic one were separated by an anionic permoselective membrane with an ionic exchange capacity and functionalized through quaternary ammonium ions. The anodic circuit of the cell foresees furthermore a recycle ratio equal to 1/30. The cathodic compartment of the cell was fed with an aqueous solution of sulfuric acid (39.2 wt.%). In the electrolytic cell occurred an anodic oxidation of the ferrous ion to ferric ion, regenerated the liquid flow, that was returned to the scrubber, while a reduction of hydrogen ions takes place at the cathode, set free a hydrogen gas flow, purity 99.98%.