Preparation Of Pericarp Derived Adsorbent And Mechanism Of Hydrogen Sulfide Removal

Hydrogen sulfide as a toxic,colorless and corrosive gas seriously harms human health and industrial production.At room temperature,activated carbon with a high specific surface area is used as a carrier an adsorbent carrier for the remove of hydrogen sulfide after modification.Generally,commercial activated carbon is prepared with coal as a raw material.If peel waste with high moisture content and low ash content is used as raw material to prepare a high sulfur capacity activated carbon-based hydrogen sulfide adsorbent,it can reduce the cost of raw materials and reduce the use of fossil energy while achieving the purpose of treating waste with waste,which is beneficial to the added value utilization of peel waste.Therefore,this paper proposes the process plan of"Hydrothermal Treatment of Peel Garbage-Activation to prepare activated carbon-Preparation of desulfurizer by modification of loaded metal"to realize the resource disposal of peel waste and the removal of hydrogen sulfide.This paper uses grapefruit peel as the raw material to study the effects of preparation conditions such as hydrothermal temperature,activation temperature,solid-alkali ratio and activation time on the properties of grapefruit peel-based activated carbon,and explores the effect of moisture,oxygen and temperature reaction conditions on the removal of hydrogen sulfide.The predetermined structure of the pomelo peel-based hydrothermal carbon obtained by hydrothermal carbonization is not developed enough,and the highest BET specific surface area is only 15.3 m²/g.After activation of KOH,the specific surface area and pore volume of the hydrothermal carbon are significantly increased.The orthogonal test was designed to determine the best preparation conditions of pomelo peel-based activated carbon（KAC）as follows:the hydrothermal carbonization temperature is 210℃,The activation temperature is700℃,and the solid-alkali ratio is 1:2.Under these conditions,the activation yield of activated carbon was 29.1%,the BET specific surface area was 1077.9 m²/g,the micropore specific surface area was 849.5 m²/g,the total pore volume was 0.6949 cm³/g,and the micropore volume was 0.5348 cm³/g.Pomelo peel-based activated carbon has weak hydrogen sulfide removal performance,so five metals such as Mg,Mn,Fe,Zn and Cu are loaded to increase its penetration sulfur capacity.The results show that Cu has the best modified effect on pomelo peel-based activated carbon.The calcination temperature will affect the valence and dispersion of copper in KAC.As the calcination temperature increases from 300℃ to 550℃,the transformation path of copper in KAC is:Cu₂（OH）₃NO₃→Cu O→Cu₂O→Cu⁰.Cu O/KAC,Cu₂O/KAC and Cu/KAC all have good removal effects on hydrogen sulfide.the best effect is the calcination temperature of 550℃and the loading of 20wt.%Cu/KAC in all cases above.In the process of removing hydrogen sulfide,the addition of water vapor and oxygen helps the removal of hydrogen sulfide.When the relative humidity of water vapor at room temperature is 80%RH and the oxygen concentration is 1%,the longest penetration time of Cu/KAC is 111 mins,and the penetration sulfur capacity is as high as 396.7mg/g.The desulfurization products of Cu/KAC are sulfide,elemental sulfur,organic sulfur and sulfate.The proportion of sulfur in each form changes with the reaction conditions,and the highest proportion of elemental sulfur is 50.19%.