Sunday, April 11, 2010

FAR FROM THE COCONUT - A SURFACTANT'S JOURNEY

In the effort to join the Green Revolution, we often see ingredients described on labels as being “from coconut”. It may look like this: Cleansing Surfactants (from Coconut). There is a name for this kind of marketing tactic of making chemical ingredients appear natural. It’s called “Green Washing.” Let’s look at how a surfactant is made and the journey from
the coconut. We will use Sodium Lauryl Sulfate, a detergent surfactant often found in pet shampoos.

Coconutsreduced


STEP ONE: EXTRACTION OF COCONUT OIL
First we have to extract the coconut oil from the coconut. The meat of the coconut is removed and dried in kilns to produce a product called “copra”. The copra is then placed in a hydraulic press and the oil is expelled. This produces virgin coconut oil which is further refined by additional heating and filtering to provide RBD oil (refined, bleached and deodorized. So far, we are still natural.

STEP TWO: EXTRACTION OF LAURIC ACID FROM COCONUT OIL
The coconut oil is then heated in water in the presence of sodium hydroxide. This converts the coconut oil into fatty acids, lauric acid and glycerin. This is a chemical process, and it’s only step two. Lauric Acid is also obtained from Palm Kernel Oil.

STEP THREE: HYDROGENATION
The lauric acid is then converted into fatty alcohol through a process of hydrogenation. Hydrogenation involves adding hydrogen atoms to the acid molecule. According to Wikipedia “Hydrogenation has three components, the unsaturated substrate, the hydrogen (or hydrogen source), and, invariably, a catalyst. The reaction is carried out at different temperatures and pressures depending upon the substrate and the activity of the catalyst.”

This is chemistry! The Lauryl Alcohol at this point bears little resemblance to the original coconut and shares few if any properties of the coconut oil.

STEP FOUR: SULFONATION
The lauryl alcohol is then converted into lauryl sulfate through a process called sulfonation. There are plants that carry out this process. The Chemithon technology was developed by research and development in Seattle. Here is a diagram of the sulfonation process by Chemithon:

Sulfonationreduced

[1. Process Air and Sulfur Supply System. 2. Feedstock (i.e., lauric acid). 3. SO3 Generator System. 4. Sulfonator System. 5. SO3 Absorber System 6. Neutralizer System 7. Exhaust Gas Clean-up System 8. Final Product. ]

Still feeling natural about your shampoo? Wait! There's more!

STEP FIVE: REACTION WITH SODIUM HYDROXIDE
In the final step (whew!), the lauryl sulfate is reacted with sodium hydroxide to form sodium lauryl sulfate (SLS). When the lauryl sulfate is reacted with ammonia instead of sodium hydroxide, you have ammonium lauryl sulfate (ALS). When triethanol amine (TEA) is used,you have TEA lauryl sulfate. Both ALS and TEA lauryl sulfate are used as alternatives to SLS.

Voila! The journey from coconut to Sodium Lauryl Sulfate is long and chemically complex. So now you know. You know that there is a significant chemical journey from the coconut to the shampoo bottle. A shampoo base (from coconut) is not exactly the same as coconut oil-in-a-bottle. You know that Sodium Lauryl Sulfate is hardly a natural substance, although it is derived from a natural substance. Green washing is the psychological ploy of associating something natural with something synthetic to make the chemical appear more natural. Sodium Lauryl Sulfate (from coconut) is the same detergent surfactant that has been around for decades, with a green shirt on.

 Coconutredwithtext SLS

1 comment:

  1. So true! I hate it when people take advantage of consumers who want to do the right thing. It seems like you have to be an expert on everything just to go shopping--even for shampoo!

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