Double System Matching For Hydrogen Sulfide Electrolysis

The indirect electrolysis of hydrogen sulfide to produce hydrogen has an important practical significance for the effective comprehensive utilization of hydrogen sulfide.Hydrogen production by hydrogen double-system electrolysis mainly involves two parts of oxidation and electrolysis,which are accompanied by the separation stage of sulfur.The whole process has a fast reaction speed,less side reactions,high sulfur recovery rate and considerable economic benefits.In this thesis,the absorption effect was improved by improving the absorption solution,and the electrolytic law of the electrolyte was studied.By adding phosphotungstic acid,lanthanum nitrate and cetyltrimethylammonium chloride,the improvement of absorption effect was investigated in a pilot plant of Shandong Qilu Petrochemical Research Institute.The experimental results show that when thereaction temperature was room temperature,the gas-liquid ratio was 1:10,and the inlet concentration of hydrogen sulfide was 50%,phosphotungstic acid had little effect on absorption.When lanthanum nitrate is added and the concentration of lanthanum nitrate was 5x10^-3 mol/L,the absorption enhancement effect was the best.The amount of cetyltrimethylammonium chloride was 0.005 mol/L,the absorption rate reached98.71%.The influencing factors of the solidified graphite electrodes were studied.The preparation conditions of the solidified graphite electrodes were as follows:hot pressing temperature 120°C,hot pressing pressure 0.1 kg/cm²,hot pressing time 4 min,intermediate polyethylene film thickness 0.2 mm.Under the optimized absorption conditions,the electrolysis voltage,the acidity of the absorption liquid,the flow rate of the electrolyte,the composition of the anode and cathode,etc.were studied,The suitable electrolysis conditions were determined.In the electrolysis regeneration system of the pilot plant,the electrolysis current density was67.64 m A/cm2 when the power consumption was 2.86 k Wh/NM³H₂.At the same time,the sulfur produced has reached the national first-class product standard and the purity of hydrogen is more than 99%.