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Sulfur removal methods

Fuel Cell Technology and Applications

Hydrogen storage and hydrogen generation

Fuel processing from hydrocarbons to hydrogen

  1. A. Hidalgo-Vivas,
  2. B. H. Cooper

Published Online: 15 DEC 2010

DOI: 10.1002/9780470974001.f302016

Handbook of Fuel Cells

Handbook of Fuel Cells

How to Cite

Hidalgo-Vivas, A. and Cooper, B. H. 2010. Sulfur removal methods. Handbook of Fuel Cells. .

Author Information

  1. Haldor Topsøoe A/S, Lyngby, Denmark

Publication History

  1. Published Online: 15 DEC 2010

Abstract

Hydrogen production processes, e.g., steam reforming and partial oxidation, begin with a pretreatment section where a sulfur removal method is employed to prepare the feedstock. The characteristics of possible reforming fuels, i.e., liquefied natural gas, liquefied petroleum gas, naphtha and diesel are discussed in a refinery context. Sulfur compounds present in crude oil fractions are divided into different classes. Some exhibit a very low reactivity, which makes them more difficult to desulfurize, and which significantly impacts the achievement of ultra-low sulfur levels. The improved design of efficient hydrodesulfurization processes is based on the understanding of the process chemistry. In the case of a feedstock with low sulfur content, removal of sulfur can be achieved by absorption processes, e.g., absorption on a zinc oxide catalyst bed. In the case of heavier feedstocks or feedstocks with a high sulfur content, a first step consisting of a hydrodesulfurization process becomes necessary. The process conditions, i.e., temperature, pressure, space velocities, catalysts, etc. are determined by the type of feedstock to be treated. The catalysts most generally used for hydrotreatment consist of cobalt and molybdenum oxides or nickel/molybdenum compounds, both supported over alumina. CoMo and NiMo catalysts desulfurize the most refractory compounds through different desulfurization routes, thus the choice of catalyst will be a function of the type of feedstock and process conditions. It is required that the hydrogen sulfide produced by the desulfurization reactions is removed. Options used to remove H2S from the system include the use of zinc oxide absorption, amine wash treatment or both.

Keywords:

  • hydrodesulfurization (HDS);
  • sulfur-containing compounds;
  • absorption;
  • zinc oxide bed;
  • HDS routes;
  • HDS catalysts;
  • H2S removal