Arabian Alchemy: Shell makes black gold in Qatar

PJ contributor Leon de Winter mailed us an article from The Volkskrant, which Leon calls the New York Times of the Netherlands (which seems damning with faint praise to me, but never mind that).  The title of the article is (roughly) "Shell's magic makes black gold from natural gas." Frustratingly, I can't get the Volksrant website to deliver me a link to the original article, but I was able to find it on Lexis, and between my small ability to read Dutch (see, you learn how the Dutch spell things, then read it out loud -- if you speak both English and German, you can make sense of it) and Google Translate, I was able to get the gist.

And it's a pretty interesting gist, I'll tell you what.

Here's the basic story: In a June 4th story, Michael Persson reports that the first product is coming from the Shell-Qatari joint project a half-hour out of Doha. The project is called "Pearl" and its function is to transform natural gas into synthetic replacements for petroleum products. In other words, turning natural gas into oil.

Conceptually the process is simple. Natural crude oil is a mix of a variety of hydrocarbons, which of course are simply molecules made of hydrogen and carbon. (This is distinct from carbohydrates like sugar, which also include oxygen.) A lot of the hydrocarbons in crude oil are long chains -- they have many carbon atoms joined together. When crude oil is refined, the refinery basically does two things: first, it separates out any naturally-occurring shorter chains, which includes things like pentane, hexane, heptane, and octane. We call a misture of those things (and some other stuff, this is a bit oversimplified) "gasoline." This isn't sufficient to provide as much gasoline as we'd like, so a catalytic process is used to convert other fractions into the right components for gasoline. Natural crude usually contains some other compounds, like sulfur compounds. When you hear the TV business people talk about "sweet crude", they mean crude with relatively little sulfer. "Sour" crude, naturally, has more sulfur. The sulfur compounds have some commercial uses, but they present processing problems, so "sour" crude is less desirable" than "sweet" crude.

The effect is that long-chain hydrocarbons are broken down into shorter chains; this process naturally releases some energy, so it's "downhill".

What Shell is doing, through a process called GTL ("gas to liquid", aren't scientists just poets?), is running a refinery backwards. Natural gas is primarily methane, the simplest hydrocarbon; the GTL process pushes it back up the hill to form longer hydrocarbon chains. This process consumes some energy, so it's a little bit counter-intuitive why you'd want to do such a thing, but there are some real advantages. First off, natural gas is hard to handle -- you can't run a pipeline across the Pacific, and storing it in tankers means either storing it under very great pressure, or cooling it to very low temperatures to make it a liquid.