Soft Oxidation (SoftOx) Process Mitigates Flaring Issues and Converts Sour Gas to Clean Liquid Fuels

SoftOx is a low-cost process that converts sour natural gas, containing high-levels of H2S, directly to sour liquid hydrocarbons and clean natural gas. The process eliminates wellhead flaring of sour gas and achieves the economical monetization of sour gas resources through a simple design that is low-cost, modular, and compact. The process takes sour gas and catalytically converts the majority of the sulfur-containing compounds and hydrocarbons into liquids that are oligomerized to increase the yields for added oil production and sweet natural gas. The remaining gas, mainly hydrogen, can be cleanly burned to provide power.

Initial testing has shown 18% per pass conversion of sour natural gas to liquids. H2S concentrations in the gas were reduced to less than 25% of the starting level as well. As much as 20 wt% ethylene is also produced from the first stage. A robust and low-cost catalyst was identified for the soft oxidation conversion. Based on modeling, it is estimated the overall conversion of the SoftOx process to liquids, with recycle, can reach 50 wt% with a 50 wt% conversion to clean natural gas containing <10ppm H2S.

The long-term stability and integration of the system, including the SoftOx and oligomerization catalysts and separation units, needs to be demonstrated at the bench- and pilot-plant scale.