Adsorption of hydrogen sulfide by activated carbon produced by regeneration of sludge from upflow anaerobic sludge blanket

Abstract

The objective of this study was to determine the efficiency of H2S adsorption by activated carbon obtained from the regeneration of sludge from an Upflow Anaerobic Sludge Blanket (UASB). The H2S adsorption system was carried out in the Chemistry laboratory of the Universidad Peruana Unión, the inflow of the fixed bed towers was 4 L·min and 36 g of adsorbent media (6 different Active Carbon (AC), depending on Pyrolization temperatures (PT) and [M] KOH), AC at PT 700 oC/1M, AC PT 500 oC/4M, AC PT 500 oC/1M, AC PT 700 oC/4Mand AC PT 600 oC/2.5 M the last with two repetitions. The adsorption of H2S was determined by the volumetric oxidation-reduction method. The parameter of the greatest influence for the adsorption of H2S was PT at 99 and 90% CI respectively, demonstrated by 22 and 32 factorial designs; satisfactory elimination efficiencies of H2S were obtained and reached 94% during a retention time of 20 minutes of activated carbon at PT 700 oC and [1M] KOH. For the response surface prediction simulation, the optimized parameters for the removal of H2S approximately greater than 96% was at PT of 635 oC and activating agent of [2.6 M] KOH. Therefore, the adsorption of H2S by activated carbons for sludge is a new, viable and sustainable alternative for the environment.