SAFE CARE® - How It Works
About the Chemistry
The basis for our cleaning chemistries are colloidal solutions comprised of plant-based non-ionic surfactants that create unique hydrocarbon release agents that can tolerate tremendous soil loads. Our feature product, SC-1000 Aqueous Cleaner, is so powerful that crude oil will be completely lifted from the cleaning surface by only a small amount of SC-1000 without causing an emulsion or damage to the cleaning surface. Powerful micelle cleaning action causes long chain hydrocarbon soils to virtually repel from the cleaning surface so that soils can be rinsed away with water.
What is a biobased surfactant? A surfactant (surface-active agents) is a compound that has two groups present in the molecule: One being hydrophobic in nature which means water-hating or oil-liking One being hydrophilic in nature which means water-liking. When you have a surfactant with two groups present, you have a chemical compound that has surface-active properties or the ability to affect the interfacial relationship between two dissimilar substances such as oil and water. The development of new surfactants has brought aqueous cleaning into a new generation. New technology aqueous cleaners clean by subverting the soil. A non-emulsifying surfactant is designed to have a higher affinity for the substrate than the soil does. The surfactant thus "lifts" the soil from the part or surface without chemically reacting with it. For example, a non-emulsifying cleaner works well in spray applications. If a settling tank and oil skimmer are added to the system, soils can be removed and the cleaning solution can be reused, sometimes indefinitely, without recontaminating parts.
What is a Colloid? A colloid, or colloidal dispersion, is a form of matter intermediate between a true solution (like salt dissolved in water) and a mixture or suspension (Italian salad dressing right after you shake it). Further research revealed that colloids have minute particles called micelles. When combined with water, micelles break water's surface tension (the property that keeps water droplets round), resulting in "super wet" water. That same action allows the micelles to penetrate grease, oil and related organic soils and to hold them in liquid suspension. In effect, the micelle cleaning action is unique and can only be related to the effect of an atomic explosion where random interaction of the particles loosens the soil.
What is a Micelle? The surfactants used by GEMTEK® consist of long molecules with two very different types of ends. One end likes water, and is called hydrophilic, the other end likes oil and dislikes water, and is called hydrophobic. When these surfactants are placed in water, the hydrophobic ends attract each other, and repel water, and arrange themselves into a spherical structure with the hydrophobic ends inside the sphere, and the hydrophilic ends on the outer surface of the sphere. This sphere is called a micelle.
This image is a representation of a micelle. The hydrophilic ends (“heads”) of the surfactant molecules are depicted as balls, and the hydrophobic ends (“tails”) are lines.
Figure “B” below is a highly schematic illustration of the manner in which the colloid particles called micelles perform in reducing surface tension of water in a very dilute solution. Each micelle is about one ten-millionth of a centimeter (0.000,000,01 cm) in size. Although the physical action is electrical in nature, it is perhaps more readily visualized with the rounded ends as “hydrophilic” or having an affinity to water. The rectangular ends may be regarded as “hydrophobic” or being antagonistic to water.
It has been demonstrated that substances such as petroleum compounds, waxes, the more complex alcohols, oil soluble dyes and other substances, which are insoluble in dilute detergent solutions will dissolve in solutions that contain these colloid particles called micelles.
In laboratory tests the dyne/centimeter surface tension of tap water had been halved by the adding of as little as 1/3250th part of SC-1000. This may serve to explain why the invention of SC-1000 allows us to constitute so many solutions from one product that can have the properties of a soap, a detergent, a solvent or other cleaner, and yet be none of these in itself, and to do so with so nearly a perfect safety factor.
What about cleaning? Cleaning is mostly about cleaning different types of hydrophobic (or oily) soils. Why? Because hydrophilic, or water-liking, soils are usually easily rinsed off with water. Micelles enable us to dissolve hydrophobic chemistries into water.
The tails of the surfactant like the oil soils as well as they do each other, and begin to orient themselves on the surface of the oily soil as shown in the diagram below. Eventually that small part of the soil lifts off of the cleaning surface and becomes part of a micelle, thus cleaning the surface.
Two important features of SC-1000 are its reusability and its poor emulsion formation. These two features actually have one single cause: the hydrophobic tails of SC-1000 readily “let go” of oils, which then float to the surface of the water where they can be removed. Soils being cleaned by SC-1000 are quickly incorporated into micelle structures. Typically, aqueous cleaners are made up of a number of different ingredients including builders, surfactants, inhibitors and chelators. Most cleaners come with a long list of ingredients, many of which you may not need for most cleaning applications. These extra ingredients may cause you extra problems, especially in wastewater treatment.
The following outlines some common types of additives along with an explanation of what they do and the advantages and disadvantages of each:
Builders: A builder is the basic ingredient of most aqueous cleaners. The most common builders are sodium hydroxide, potassium hydroxide and sodium silicates. All of these are alkalines and all are slimy and hard to rinse. Remember that proper rinsing is the most important step in aqueous cleaning.
Inhibitors: Inhibitors are used to reduce the effects of highly alkaline or acidic cleaners on sensitive substrates. Inhibitors are also used to prevent rusting or oxidation of parts after cleaning. Chromates and silicates are commonly used pH inhibitors, but chromates have obvious environmental disadvantages. Hydroxides and silicates are commonly used to prevent rust. Inhibitors may make rinsing more difficult.
Chelating Agents: Chelators are designed to keep metal ions in solution so that they will not migrate to adjoining surfaces.
Sequestering Agents: Many alkaline cleaners are sensitive to the condition of incoming process water. Sequestering agents are used to 'capture' hard water ions such as calcium and magnesium, thus allowing the cleaner to work at maximum efficiency.
Saponification: Highly alkaline cleaners can convert insoluble fatty soils to water soluble soaps. This will keep the soils in solution and the additional soap may aid cleaning, however it also causes disposal problems. Soaps created by saponification may cause a foaming problem in spray or ultrasonic applications.
Emulsifiers: Emulsifiers take oils into solution and keep them from re-contaminating parts. This is useful in an immersion tank, but the more parts you clean, the dirtier the water gets until the bath becomes useless, requiring disposal. Before disposal, the emulsion must be "cracked" or ultra-filtered to remove the oils. Cracking requires either heat or acid plus time and money and then the bath must be refilled.
What about pH? The effect of pH measurement (hydrogen v. hydroxil ions) in the SAFE CARE® aqueous products is of lesser importance because the products do not rely upon pH for cleaning, but rather on the unique properties of colloidal micelles which are formed almost independently of their solution pH. Salt-based chemistries such as Caustic Soda must rely on higher alkaline reserve numbers to achieve cleaning results. The natural pH of the surfactants, fatty acids and saponifers used by GEMTEK® are in the mid-alkalinity range and are not typically changed artificially. The alkaline reserve numbers for the products (measurement of ability to resist change to acid) are typically very low.
What are Dispersants? Solubilizer v. Emulsifier
A solubilizer such as SC-1000 provides certain important advantages when compared to traditional dispersants and emulsifiers.
In the process of oil spill clean up, the use of dispersants to disperse crude oils and oil derivatives may include other petroleum solvents and certain aqueous cleaning surfactants which serve to separate oil molecules and aid clean up. The task of separating oil molecules is made more difficult if an emulsion is formed.
In the following discussion, the term solubilizer will refer to a water miscible solvent that thins oil down to molecular sized particles and keeps them separated without reacting with the molecular structure of oil. The term dispersant will refer to any chemistry that serves the purpose of separating oil molecules regardless to what magnitude. And, emulsifiers will be referred to as chemicals which cause a colloidal suspension of oil in water that is generally irreversible and makes the separation or recapture of the oil molecule or coagulation of oil molecules apart from water practically impossible.
- Cause homogenous mixture (evenly blended into small droplets) of two or more miscible substances which do not interact with each other to form different chemistries
- Cause subdivision down to molecular magnitude
- Cause a solution of different chemicals that do not settle into different layers or apart from each other
- Do not require a fixed proportion of oil and solubilizer to cause separation
- Are a precise relationship of oil, water and solvent
- Are generally irreversible in practical short term applications, such as a few hours or a couple days in a natural environment
- Lock up the entire petroleum hydrocarbon which then is unavailable for ready biodegradation by available bio-organisms and natural environmental processes
- Prevent the separation of petroleum hydrocarbons, which depletes available oxygen for natural organisms
- Are colloidal suspensions which encapsulate small droplets of petroleum hydrocarbons
Effectively solubilizers simply act to separate oil molecules into fine droplets, while emulsifiers act to encapsulate the oil molecule in a colloidal suspension which then hampers oil water separation for clean-up.
Historically, dispersants have been used to simply separate or thin oil spills so that they were more manageable and to recover the oil or oily sludge in the case of degraded crude. It was not important until very recent years whether the dispersant was toxic itself, but only that the oil was recoverable from ocean surfaces, boats, beach surfaces and marine animals. Dispersants were largely based upon straight solvent technologies and included aliphatic alcohols, petroleum distillates, terpenes and glycol ethers, all of which are now known to be toxic and/or carcinogenic. However, they are able to effectively thin various types of crude oils and even blended oils for recovery as long as the ocean surface was relatively calm.
As much as 85% of these dispersants would end up contaminating the ocean environment, including the volatiles they released into the air. In the case of a large mat of vicious crude floating over miles of ocean, spraying dispersant becomes less effective as oil ages in the water column and will generally from emulsions or characteristic mousse (diagram of chocolate mousse). At this point, oil in emulsion is extremely difficult to skim, pump or separate because it has become a colloidal suspension or approximately 80% water. Emulsions prevent ready biodegradation because the oily soil is locked into colloidal suspension and ready access to constituent molecules of carbon, hydrogen and elemental metals are blocked by powerful solvating bonds. Unless opposite conditions exist that first formed the colloidal suspension or emulsion, they will persist for indefinite periods of time. And, though the water phase emulsion may be diluted further, the colloidal suspension does not necessarily revert to coagulation of oil molecules so that they may be recovered by mechanical means or environmentally degraded by wave action and indigenous microorganisms.
Since the advent of organic solvents and aqueous cleaners and degreaser surfactants in the 1980’s onward, dispersants have increasingly relied on less environmentally invasive chemicals which readily biodegrade and, in many cases, work adequately as dispersants; that is they thin the oily mess. However, as with many traditional solvents, the new surfactants cause ready emulsions with oil once introduced to the water surface. While historically this was not a problem when environmental concerns were less important, simply thinning oil into an emulsion without improving the chances of biodegradation are no longer enough. Now total recovery of the petroleum hydrocarbon is the prevailing popular mandate.
What is a biobased solvent?
The SAFE CARE® Safety Solvents manufactured by GEMTEK® are non-polar plant-based solvents which provide the same or higher performance characteristics of traditional halogenated or chlorinated solvents with few or none of the disadvantages. SAFE CARE® Safety Solvents include solvents that are water miscible and non-miscible and 100% evaporative and non-evaporative with Kauri Butinal (KB) values ranging from 150 to over 1000.
The SAFE CARE® Safety Solvents do not compromise on their performance by easily exceeding the highest values available for chlorinated solvents such as 1,1,1-Trichloroethane, Xylene or Methyl Ethyl Ketone (MEK). Generally, SAFE CARE® Safety Solvents are non-reactive with cleaning surfaces including elastomerics such as viton, butyl, nylon, acrylics, HDPE/LDPE, styrenes, urethanes, vinyls and most inorganic paints and coatings.
SAFE CARE® Safety Solvents are derived from alcohols and esters of soy, corn, rice, palm, cottonseed, linseed, safflower, sunflower, Jojoba soil, Jatropha, mustard, walnut and almond oils which are all readily biodegradable and non-toxic.