Monday 29 June 2015

Understanding Acids and Alkalinity




Don't Play Mad Scientist

Just remember that anytime two chemicals with completely different formulas and / or functions are combined, at best the effectiveness of each chemical is reduced, and/or the chemicals may not be compatible

Don't haphazardly mix chemicals; pay attention to the order in which chemicals are to be added to each other and do not deviate from the instructions. Even chemicals that mix to produce seemingly safe products should be handled carefully.

For example, hydrochloric acid and sodium hydroxide will give you salt water, but the reaction could break your glassware or splash the reactants onto you if you aren't careful. Some rules are NOT made to be broken. That is true of the rules used for chemicals. They are established for your safety and those of other’s

What is the difference between an acid and an alkali?

The strength of the acidity or alkalinity is expressed by the pH scale. An acid usually has a chemical formula with H at the beginning of, its strength depends on its concentration of the hydronium ions. A base (Alkali) has a chemical formula with OH at the end of it, its strength      depends on concentration of the hydroxide ions

An acid (often represented by the generic formula HA) is traditionally considered any chemical compound that when dissolved in water yields hydronium ions as the only positive charged ions and gives a solution with a pH of less than 7. That approximates the modern definition of Brønsted and Lowry, who defined an acid as a compound which donates a hydrogen ion (H+) to another compound (called a base). Common examples include acetic acid (in vinegar) and sulfuric acid (used in car batteries). Acids generally taste sour

In chemistry, an alkali is a compound which when dissolved in water yields hydroxyl ions as only negative charged ions, an alkali is a specific type of base, formed as a carbonate, hydroxide or other basic (pH greater than 7) ionic salt of an alkali metal or alkali earth metal element. The word alkali or the adjective alkaline are frequently used to refer to all bases, since most common bases are alkalis, although strictly speaking this is inaccurate.

Types of Acids and Bases (Alkali)

Acids can be classified as Mineral acids, Sulfonic acids, Carboxylic acids, Vinylogous carboxylic acids and Nucleic acids. Some common acids include Hydrochloric acid (HCl), Sulphuric acid (H2SO4), Nitric Acid (HNO3), Acetic acid, Citric acid and Lactic acid amongst several others.
Bases are of 2 types – a base and an alkali (a soluble base). Some common bases include Potassium Hydroxide (KOH), Sodium Hydroxide (NaOH) and Magnesium Hydroxide (Mg (OH) 2).
pH measurement
The term pH is a measurement of the relationship between hydrogen ions and hydroxyl ions.  When you have more hydrogen ions than hydroxyl ions, you have an acid.  Likewise, if you have more hydroxyl ions than hydrogen ions you have a base (alkali).
The pH scale is a measure of the acidity or basicity (Alkali) of a solution. It is approximates but is not equal to p [H], the negative logarithm base 10) Base (Acid) 1-7, Alkaline 7- 14; the pH of a solution is temperature-dependent.
Unfortunately the pH scale is logarithmic; for every integer that the scale decreases the material is 10 times more acidic. Those of us in earthquake country know all too well the consequences of a change of from 6 to 7 on the logarithmic, Richter scale. The difference in the pH scale is just as dramatic and therefore just as misleading.

Be cognizant that an acid or high alkaline product should not be allowed to dry on the surface since their aggressiveness continuously increases as the water is evaporated. Also, as they are heated (reactivity) they become more aggressive.

Base (Alkali)

Alkalis neutralize acids, and solutions of alkali are greasy to the touch. The strength of an alkali is measured by its hydrogen-ion concentration, indicated by the pH value.

They may be divided into strong and weak alkali: a strong alkali (for example, potassium hydroxide, KOH) ionizes completely when dissolved in water, whereas a weak alkali (for example, ammonium hydroxide, NH4OH) exists in a partially ionized state in solution. All alkalis have a pH above 7.0.
The hydroxides of metals are alkalis. Those of sodium and potassium are corrosive; both were historically derived from the ashes of plants.

The four main alkali are-
1.        Sodium hydroxide (caustic soda, NaOH)
2.        Potassium hydroxide (caustic potash, KOH)
3.        Hydroxide calcium (slaked lime or limewater, Ca (OH) 2)
4.        Aqueous ammonia (NH3 (aq)). Their solutions all contain the hydroxide ion OH-, which gives them a characteristic set of properties.

Strength of an Acid in Solution

Acid [: (from the Latin acidus meaning sour) is a chemical substance whose aqueous solutions are characterized by a sour taste, the ability to turn blue litmus red, and the ability to react with bases and certain metals (like calcium) to form salts. Aqueous solutions of acids have a pH of less than 7]

An acid dissociation constant, Acidity (pKa) (also known as acidity constant) is a quantitative measure of the strength of an acid in solution.
·         Hydrofluoric acid - 3.17
·         Hydrogen peroxide - 11.7
·         Oxalic acid - 1.27
·         Hydrogen sulphate - 1.99
·         Citric acid - 3.128
·         Acetic acid - 4.756

Acid

Strong acids include the heavier hydrophilic acids: however, Hydrofluoric Acid (HF) is relatively weak. Acids are acids by virtue of the presence of an excess of hydrogen ions in the solution, Their salts are created when the positive hydrogen ions are replaced with positive metal ions, for example when Hydrochloric Acid (HCL) reacts with Sodium (Na) to produce NaCl with the release of H2 gas.

1.                    Hydrochloric Acid (HCI): or Muriatic Acid, its historical but still occasionally used name, this is a highly corrosive acid (pH of -1) and is often used to clean calcium carbonate build up from the inside of kettles or from around water faucets and from shower heads;
2.                    Sulphuric Acid (H2 SO4): this is a common acid in both the laboratory and industry. It is both highly corrosive and economical to manufacture, which makes it the reagent of choice for many applications;
3.                    Phosphoric Acid (H3PO4): this acid is used to remove rust and rust stains from metal tools and from car bodies undergoing repairs;
4.                    Nitric Acid (HNO): this is another common laboratory acid used as a reagent in many chemical tests and experiments due to the fact that almost all of its products (salts) are soluble in water;

5.                    Hydrofluoric Acid (HF): This acid is extremely corrosive and has the unique property of being able to etch (eat away) glass. Consequently it is used in industry to write signs on glass windows in stores and office buildings or on glass products. 

Acids, Bases, and pH

Water quality and pH are often mentioned in the same sentence. The pH is a very important factor, because certain chemical processes can only take place when water has a certain pH. For instance, chlorine reactions only take place when the pH has a value of between 6.5 and 8.

pH literally means the weight of hydrogen. pH is an indication for the number of hydrogen ions. It consisted when we discovered that water consists of hydrogen ions (H+) and hydroxide ions (OH-). pH is an indication for the acidity of a substance. It is determined by the number of free hydrogen ions (H+) in a substance. The common term for pH is alkalinity.

Acidity is one of the most important properties of water. Water is a solvent for nearly all ions. The pH serves as an indicator that compares some of the most water-soluble ions. The outcome of a pH-measurement is determined by a consideration between the number of H+ ions and the number of hydroxide (OH-) ions. When the number of H+ ions equals the number of OH- ions, the water is neutral. It will than have a pH of about 7.

The pH of water can vary between 0 and 14. When the pH of a substance is above 7, it is a basic substance. When the pH of a substance is below 7, it is an acid substance. The further the pH lies above or below 7, the more basic or acid a solution is.

The pH is a logarithmic factor; when a solution becomes ten times more acidic, the pH will fall by one unit. When a solution becomes a hundred times more acidic the pH will fall by two units.

Total alkalinity

Is frequently referred to as AT, defined as the amount of acid required to lower the pH of the sample to the point where all of the bicarbonate [HCO3-] and carbonate [CO3-] could be converted to carbonic acid [H2CO3]. This is called the carbonic acid equivalence point or the carbonic acid endpoint.

When an acid substance ends up in water, it will give up a hydrogen ion to the water. The water will than become acid. The number of hydrogen ions that the water will receive determines the pH. When a basic substance enters the water it will take up hydrogen ions. This will lower the pH of the water. When a substance is strongly acidic it will give up more H+ ions to the water. Strong bases will give up more OH

There are several ways to define acids and bases, but pH only refers to hydrogen ion concentration and is only meaningful when applied to aqueous (water-based) solutions. When water dissociates it yields a hydrogen ion and a hydroxide.


Pure water is said to be neutral, with a pH close to 7.0 at 25 °C (77 °F). Solutions with a pH less than 7 are said to be acidic and solutions with a pH greater than 7 are said to be basic or alkaline.

The following is a generalized list of examples of pH:
·         pH 0 ­ battery acid
·         pH 1 ­ hydrochloric acid
·         pH 2 ­ lemon juice, vinegar
·         pH 3 ­ grapefruit
·         pH 4 ­ tomato juice
·         pH 5 ­ black coffee
·         pH 6 ­ urine/saliva – acidic ^

·         pH 7 ­ fresh water, milk – Neutral

·         pH 8 ­ sea water – base substances (alkali)  v
·         pH 9 ­ baking soda
·         pH 10 ­ Milk of Magnesia®
·         pH 11 ­ ammonia
·         pH 12 ­ soap
·         pH 13 ­ bleach
·         pH 14 ­ liquid drain cleaner

Reactivity

Add moisture (dew, rain, car washing etc.) and heat to this equation (reactivity) all of which equates to a highly concentrated solution, which causes a concave indentation (etching or alkaline staining) to the paint surface. This must be neutralized to stop the ongoing reaction process as moisture acts as a catalyst and a carrier system, which will permeate the paint system matrix.

Neutralization of acids and bases

When an alkali is added to an acid, the pH of the mixture rises as the alkali reacts with it, forming neutral products. An acid added to an alkali causes the pH to fall because the alkali is removed by reaction with the acid. A reaction in which acidity or alkalinity is removed is called neutralisation. A neutralisation involving an acid and a base (or alkali) always produces salt and water (and nothing else).

If the affected paintwork is not neutralized any remaining acid residue will be reactivated each time it comes into contact with moisture and heat. Water contains 2- hydrogen and 1-oxygen atom and will acts as a catalyst and a carrier system for acid. Oxygen is an oxidizer; ozone is an allotropic form of oxygen (an oxidizer is any component that emits oxygen); many chemical compounds react to slight heating and an oxidizing process.

Sodium bicarbonate or sodium hydrogen carbonate is the chemical compound with the formula NaHCO3Many laboratories keep a bottle of sodium bicarbonate powder within easy reach, because sodium bicarbonate is amphoteric, reacting with acids and bases. Furthermore, as it is relatively innocuous in most situations, there is no harm in using excess sodium bicarbonate

Surface preparation - wash and then clean the paint surface by using a chemical paint cleaner (Klasse all in one (AIO) or ValuGuard "N" New Car Prep

Acid - ValuGuard Acid Neutralizer (Step I) - diluted 1:8 with distilled water it neutralizes acids deposited on the paint surface and in the micro-pores of the paint

Base (Alkalis)
- ValuGuard Alkaline Neutralizer (Step II) - deep-cleans painted surfaces to remove alkaline deposits

Acid / Alkali Etching Removal –

1.        First clean the paint surface and then neutralize the acid or alkali
2.        Use a machine polish (Optimum Polish, Optimum Compound) and a cutting (LC White, Orange or Yellow) foam pad (speed # 4- 5.0 or 1200 RPM) to level the surface
3.        For PPG CeramiClear™ Clear Coat or other hard clear coats substitute Menzerna for machine polish; i.e. PO 203 S - Power Finish
4.        Use the least aggressive polish/foam pad first, if this doesn’t remove the problem step-up to a more aggressive polish / foam pad set-up
5.        If none of the above remove the etching use a wet-sanding process with 2000, 2500 and then  3000 (or 4000) grit finishing paper

I would like to think that these articles become an asset to anyone who is new to detailing and to professionals alike, as well as industry experts who seek to advance their knowledge.

I hope the above article was informative. By having some understanding of the ‘What’ and ‘Why’ as well as the ‘How’ along with a little science to help you understand how the chemicals we use react, you can achieve the results you desire.

I would appreciate it if you would share this article as it helps other detailers further their knowledge. Questions and/ or constructive comments are always appreciated.


Copyright © 2002 - 2012 TOGWT® (Established 1980) all rights reserved



Sunday 28 June 2015

Ceramic Brakes - Rotors- Callipers



Rotors
Zinc Aero Rotors are available either drilled or slotted, an optional anti-corrosion gold zinc coating benefits those who live in cold climates, where snow and road salt are commonly encountered. Zinc coating also benefits Concours d’Ă©lĂ©gance detailers who prefer no visible surface rust on the vanes and outer circumference of rotors Quick Stop Pro

Disc Brake Bedding In

All cast iron brake discs need to be bedded-in to ensure heat stabilisation and improve resistance to cracking. Cracks or even disc failure can occur during the first few heavy stops if careful bedding is not carried out. 

AP Racing recommends the following procedure:-
Bedding the disc from new or stress relieving the cast iron disc after it has been clamped to the mounting bell is of paramount importance if premature warping is to be avoided after the brakes are used to their full potential.

For road car installations the process needs to be as follows:-

For the first 10 miles, light braking from 50/60 mph down to 30 mph if possible in blocks of 5. Do not attempt any high-speed stops down to zero at this point, as only the faces will heat up with the mass remaining cool along with the mounting area. For the next 100 miles increase the braking pressures similar to stopping in traffic, again avoiding if possible full stops from above 70 mph. By now the area around the mounting bolts should be a light blue temper colour.

This is a good indication that the correct heat soak has been achieved. For the next 100 miles gradually increase the braking effort after this full power stops can be used. The disc should now be an even dark to light blue temper colour, depending on the pad type and the braking effort being used during the process. 



Ceramic Brakes

Silicon-infiltrated carbon-carbon composite is used for high performance ceramic brake discs, as it is able to withstand extreme temperatures. The silicon reacts with the graphite in the carbon-carbon composite to become carbon-fibre-reinforced silicon carbide (C/SiC). 

These discs are used on some road-going sports cars, supercars, as well as other performance cars including the Porsche, the Bugatti Veyron, the Chevrolet Corvette ZR1, Bentleys, Ferraris, Lamborghinis, some specific high performance Audis, and the McLaren P1. Silicon carbide is also used in a sintered form for diesel particulate filters. SiC is also used as an oil additive to reduce friction, emissions, and harmonics.

Cleaning - do not use any products that contain silicone (which means any spray type products) If the silicone "impregnates" they will require replacement (a not inexpensive mistake). Use a non-abrasive car wash concentrate and water along with a medium-soft brush.)

Ceramic Disc Pads

Asbestos pads caused health issues and organic compounds can’t always meet a wide range of braking requirements. Unfortunately the steel strands used in semi-metallic pads to provide strength and conduct heat away from rotors also generate noise and are abrasive enough to increase rotor wear. Wear also cause ferrous oxide dust that looks unsightly and is also corrosive. 

First used as original equipment manufacturer (OEM) in ’85, friction materials that contain ceramic formulations

Ensure that the ceramic brake pads and rotors match (a ceramic system) otherwise you will have problems with stopping when the pads / rotors are cold or wet, which could warp the rotors and cause bearings to fail due to overheating.

Although a ceramic brake disc absorbs heat faster than a steel brake disc, it is also able to disperse it quickly. A consistently high braking performance is therefore guaranteed.

One of the characteristics that make ceramic materials attractive is the absence of noticeable dust. All brake pads produce dust (including ceramics) as they wear. The ingredients in ceramic compounds produce a light coloured dust that is much less noticeable and less likely to stick to the wheels. Consequently, wheels and tires maintain a cleaner appearance longer.

To avoid brake-generated noise and dust brake friction materials have evolved significantly over the years, going from asbestos to organic to semi-metallic formulations. Each of these materials has proven to have advantages and disadvantages regarding environmental friendliness, wear, and noise and stopping capability.

Using ceramic compounds and copper fibres in place of the semi-metallic pad’s steel fibres, allows the ceramic pads to handle high brake temperatures with less heat fade, provide faster recovery after a stop, and generate less dust and wear on both the pads and rotors.

From a comfort standpoint, ceramic compounds provide much quieter braking because the ceramic compound helps dampen noise by generating a frequency beyond the human hearing range. Another characteristic that makes ceramic materials attractive is the absence of noticeable dust. All brake pads produce dust as they wear. The ingredients in ceramic compounds produce a light coloured dust that is much less noticeable; consequently, wheels and tires maintain a cleaner appearance longer.

Ceramic pads meet or exceed all OEM standards for durability, stopping distance and noise. According to durability tests, ceramic compounds extend brake life compared to most other semi-metallic and organic materials and outlast other premium pad materials by a significant margin; with no sacrifice in noise control, pad life or braking performance. What is important though is that car's rotors are designed for ceramic pads; otherwise the rotors will typically wear faster. (Check with the vehicle manufacturer)

Avoid using any products that contain silicone as it can permeate the carbon-ceramic material and negatively affect the friction and thereby the braking efficiency.

Stopping Distances
At the speeds that stopping distance is generally measured from (60 to 70 MPH), the test is primarily testing the tyres grip on the pavement. As delivered from the manufacturer, nearly all vehicles are able to engage the ABS or lock the wheels at these speeds.

Therefore, an increase in braking power will do nothing to stop the vehicle in a shorter distance. For this reason, we do not record stopping distances at this time. The Brembo brake systems will show their greatest advantages when braking from higher speeds, or when tasked with repeated heavy braking.

Cleaning

Any diluted car wash concentrate, d-limonene (citrus) based cleaner (P21S® High Performance Total Auto Wash) or pH neutral cleaner (P21S Wheel Cleaner) should be fine to use on ceramic brakes as they produce very little brake dust (being non-metallic) they just attract the normal amount of road dust, dirt and grime

Safe Degreaser

If you want to safely degrease your braking components, Optimum Power Clean is an excellent choice. It is an environmentally safe product that can also clean your paint, wheels, tires, engine bay, wheel wells, trim and etc. The strong cleaning agents break down bug smear, road grime, brake dust, dirt, etc. Optimum Power Clean is also a great value because you can dilute it 3:1 with distilled water or use it full strength. 





Callipers

Brake callipers are cast ductile iron on most production cars, on ultra-high performance cars they are usually aluminium.  A way to spice up the look and at the same time protects the callipers from corrosion. The Calliper Paint System features aircraft quality paint, available in six different high gloss colours, Red, Yellow, Blue, Silver, Black, & Purple. 

The paint is heat resistant up to 925oF; this paint won't start running into your brake pads, it also seals and protects against corrosion.
Brake dust and dirt will not adhere to the calliper surface since adding the paint. The kit includes everything you'll need to get the job done, besides paint you'll also get reactor (special bonding agent), high tech calliper cleaner, mixing sticks, and a brush. Do not attempt to paint the rotor contact surface.

Application- a multi-layer gives the best results; the first coat thin, second coat medium thickness, allowing cure/dry time between coats and the final coat will act as filler, providing a gloss finish. G2-Performance Engineering Inc

Cleaning- use caution when cleaning as the finish on some callipers use a powder coating (Brembo, etc.) that can be stained by some wheel cleaners. Always ensure that the brake callipers are cool to the touch; never use a cleaner on hot callipers, wheels or brakes. 

Use a pH balanced cleaner just for an extra level of safety. Spray the cool calliper with d-limonene (citrus) based solvent P21S® Wheel Cleaner Gel or P21S® Polishing Soap, which contains micro-abrasives, agitate with a soft brush (Swissvax Detail Brush) and then rinse off with clean water. Wipe surfaces with a soft wash mitt, sponge or micro fibre towel.

Protection - apply a protection to the face of the calliper using a polymer sealant (the melting point of most waxes is too low for the heat attained by wheel / calliper surfaces) similar to that used on your paint (Modesta B-06, Wheel Wax, Zanio, Duragloss, Opti-Seal, etc.)

Always be willing to learn; because the more you learn, the more you’ll realize what you don’t know.
It is said that knowledge is power, with the caveat that it includes access to a reliable information sources. I would like to think that these articles become an asset to anyone who is new to detailing and to professional’s alike, as well as industry experts who seek to advance their knowledge.
I hope the article are informative. By having some understanding of the ‘What’ and ‘Why’ as well as the ‘How’ along with a little science to help you understand how the chemicals we use react, you can achieve the results you desire.
I would appreciate it if you would share these articles as it helps other detailers further their knowledge.
As always if you have questions, I’ll do my best to answer; bear in mind the only stupid questions is the one that was unasked. Questions and/ or constructive comments are always appreciated
Copyright © 2002 - 2015 TOGWT® (Established 1980) all rights reserved



The chemical similarities and differences in Modesta and Opti- Coat Pro Coatings


The similarities and differences in coatings available on the market are quite striking.
All true coatings are ceramic based, ceramic being a term meaning inorganic. Organics such as sealants are carbon based and as such wear away over time, ceramic in itself is permanent, being as its inorganic. 

True coatings are characterised by their silicon content (not silicone), and 2 principal variations of silicon are used. The most common is Silicon Dioxide, sometimes marketed as glass, quartz or ceramic, and in all cases that’s true.  SiO2 is suspended in a resin in the form of nano particles of Silicon Dioxide, and the resins suspend this in a film over the paint.  SiO2 has a melting point of 1,600 °C (2,910 °F; 1,870 K) and on the Mohs scale of hardness is 7

The other coating system is Silicon Carbide (SiC) Opti-Coat Pro is the only coating available that harnesses the strengths of Silicon Carbide (sometimes referred to as ceramic, industrial diamonds and carborundum. Unlike SiO2 based coatings the SiC based coating actually bonds to the paint and the SiC is formed as a chemical reaction in that process, not by having Nano particles of the ceramic floating in a resin. SiC is superior to SiO2 coatings chemically and has a melting point of 2,730 °C (4,950 °F; 3,000 K) and is a 9 on the Mohs scale of hardness.



Opti-Coat Pro is unique in many ways because of this fundamental difference in chemistry. Opti-Coat–Pro becomes one with the paint instead of suspending nano particles of a harder substance in a resin. This gives Opti-Coat Pro far superior chemical resistance, as the chemical must break down the SiC, and not break down a resin holding SiO2 nano particles.  OCP is harder than other coatings, but no coating is scratch proof. 

To obtain maximum strength other coatings require heat curing, with OCP that’s not required. SiO2 coatings obtain their maximum gloss immediately, and that gloss drops off over time, Opti-Coat Pro obtains its maximum gloss once the polymerization process is completed (roughly 7 days).  Opti-Coat Pro will maintain its gloss over time, SiO2   coatings start losing their gloss through oxidation and it continues to drop, requiring the need to add periodically some form of resin to maintain or restore the gloss and protection.
I would like to think that these articles become an asset to anyone who is new to detailing and to professionals alike, as well as industry experts who seek to advance their knowledge.

I hope the above article was informative. By having some understanding of the ‘What’ and ‘Why’ as well as the ‘How’ along with a little science to help you understand how the chemicals we use react, you can achieve the results you desire.

I would appreciate it if you would share this article as it helps other detailers further their knowledge.
Questions and/ or constructive comments are always appreciated.



Copyright © 2002 - 2012 TOGWT® (Established 1980) all rights reserved

What is needed to achieve effective cleaning

Basic Cleaning Requirements

As with all detailing tasks; surface preparation is the most important step to achieving e a flawless finish. The final result can only be as good as the surface it’s applied to; so surface preparation is of paramount importance. Products will properly bond to a substrate and that will ensure it works correctly, and has both durability and desired aesthetics

 Three types of energy are required;
                      Chemical energy- provided by the synthetic cleaner
                      Kinetic (abrasion) energy provided by machine or hand
                      Thermal energy -provided by warm or hot water

Test cleaner on an inconspicuous area then allowing it to dry to make sure the solution does not react with the surface, is the best way to ensure there are no surprises as to its affect, but be cognizant that it may not react in exactly the same way as a heavily soiled area or that has been subjected to UV-B radiation (faded)

Providing the cleaning product selected is suitable, apply several drops of the selected cleaning solution in an inconspicuous area and rub gently with a clean, white micro fibre towel. Do not over wet. Use small amounts of the product and blot frequently, do not rub or use too much pressure.   Do not use the product if it adversely changes your fabric's colour or texture.

Cleaning products (with the exception of glass cleaners) should be sprayed on to a folded 100% micro fibre cotton towel, do not spray any cleaning product  directly to the surface, as this may cause ‘spot or streak’ clean patches on the surface

Use a high-quality cleaner, formulated without strong solvents and one that has a pH value between 4 and 10 (neither strongly acidic nor strongly alkaline).To understand what is needed to achieve effective cleaning, it is helpful to have a basic knowledge of soap and detergent chemistry.

Water surface tension
Water is the liquid commonly used for cleaning, has a property called surface tension. In the body of the water, each molecule is surrounded and attracted by other water molecules. However, at the surface, those molecules are surrounded by other water molecules only on the water side. A tension is created as the water molecules at the surface are pulled into the body of the water. 

This tension causes water to bead up on surfaces (glass, fabric), which slows wetting of the surface and inhibits the cleaning process. You can see surface tension at work by placing a drop of water onto a counter top. The drop will hold its shape and will not spread.

Surfactant

In the cleaning process, surface tension must be reduced so water can spread and wet surfaces. Chemicals that are able to do this effectively are called surface active agents, or surfactants. They are said to make water "wetter."

Surfactants perform other important functions in cleaning, such as loosening, emulsifying sink dishes (dispersing in water) and holding soil in suspension until it can be rinsed away. Surfactants can also provide alkalinity, which is useful in removing acidic soils.

Surfactants are classified by their ionic (electrical charge) properties in water: anionic (negative charge), non-ionic (no charge), cationic (positive charge) and amphoteric (either positive or negative charge).
Soap is an anionic surfactant. Other anionic as well as non-ionic surfactants are the main ingredients in today's detergents. Now let's look closer at the chemistry of surfactants.

Soaps

Soaps are water-soluble sodium or potassium salts of fatty acids. Soaps are made from fats and oils, or their fatty acids, by treating them chemically with a strong alkali.
First let's examine the composition of fats, oils and alkalis; then we'll review the soap making process.

Fats and Oils

The fats and oils used in soap making come from animal or plant sources. Each fat or oil is made up of a distinctive mixture of several different triglycerides.

In a triglyceride molecule, three fatty acid molecules are attached to one molecule of glycerine. There are many types of triglycerides; each type consists of its own particular combination of fatty acids.
Fatty acids are the components of fats and oils that are used in making soap. They are weak acids composed of two parts:

A carboxylic acid group consisting of one hydrogen (H) atom, two oxygen (O) atoms, and one carbon (C) atom, plus a hydrocarbon chain attached to the carboxylic acid group. Generally, it is made up of a long straight chain of carbon (C) atoms each carrying two hydrogen (H) atoms.

Alkali

An alkali is a soluble salt of an alkali metal like sodium or potassium. Originally, the alkalis used in soap making were obtained from the ashes of plants, but they are now made commercially. Today, the term alkali describes a substance that chemically is a base (the opposite of an acid) and that reacts with and neutralizes an acid.

The common alkalis used in soap making are sodium hydroxide (NaOH), also called caustic soda; and potassium Chemhydroxide (KOH), and also called caustic potash.

How Soaps are made

Saponification of fats and oils is the most widely used soap making process. This method involves heating fats and oils and reacting them with a liquid alkali to produce soap and water (neat soap) plus glycerine.

The other major soap making process is the neutralization of fatty acids with an alkali. Fats and oils are hydrolysed (split) with a high-pressure steam to yield crude fatty acids and glycerine. The fatty acids are then purified by distillation and neutralized with an alkali to produce soap and water (neat soap).

When the alkali is sodium hydroxide, a sodium soap is formed. Sodium soaps are "hard" soaps. When the alkali is potassium hydroxide, a potassium soap is formed. Potassium soaps are softer and are found in some liquid hand soaps and shaving creams.

The carboxylate end of the soap molecule is attracted to water. It is called the hydrophilic (water-loving) 10Chemend. The hydrocarbon chain is attracted to oil and grease and repelled by water. It is known as the hydrophobic (water-hating) end.

How Water Hardness Affects Cleaning Action

Although soap is a good cleaning agent, its effectiveness is reduced when used in hard water. Hardness in water is caused by the presence of mineral salts - mostly those of calcium (Ca) and magnesium (Mg), but sometimes also iron (Fe) and manganese (Mn). The mineral salts react with soap to form an insoluble precipitate known as soap film or scum.

Soap film does not rinse away easily. It tends to remain behind and produces visible deposits on clothing and makes fabrics feel stiff. It also attaches to the insides of bathtubs, sinks and washing machines.
Some soap is used up by reacting with hard water minerals to form the film. This reduces the amount of soap available for cleaning. Even when clothes are washed in soft water, some hardness minerals are introduced by the soil on clothes. Soap molecules are not very versatile and cannot be adapted to today's variety of fibres, washing temperatures and water conditions.

Surfactants in Detergents

A detergent is an effective cleaning product because it contains one or more surfactants. Because of their chemical makeup, the surfactants used in detergents can be engineered to perform well under a variety of conditions. Such surfactants are less sensitive than soap to the hardness minerals in water and most will not form a film.

Detergent surfactants were developed in response to a shortage of animal and vegetable fats and oils during World War I and World War II. In addition, a substance that was resistant to hard water was needed to make cleaning more effective. At that time, petroleum was found to be a plentiful source for the manufacture of these surfactants. Today, detergent surfactants are made from a variety of petrochemicals (derived from petroleum) and/or oleo chemicals (derived from fats and oils).

Petrochemicals and Oleo chemicals

Like the fatty acids used in soap making, both petroleum and fats and oils contain hydrocarbon chains that are repelled by water but attracted to oil and grease in soils. These hydrocarbon chain sources are used to make the water-hating end of the surfactant molecule.

Other Chemicals
Chemicals, such as sulphur trioxide, sulphuric acid and ethylene oxide, are used to produce the water-loving end of the surfactant molecule.
Alkalis
As in soap making, an alkali is used to make detergent surfactants. Sodium and potassium hydroxide are the most common alkalis.

How Detergent Surfactants Are Made

Anionic Surfactants
The chemical reacts with hydrocarbons derived from petroleum or fats and oils to produce new acids similar to fatty acids.
A second reaction adds an alkali to the new acids to produce one type of anionic surfactant molecule.

Non-ionic Surfactants
Non-ionic surfactant molecules are produced by first converting the hydrocarbon to an alcohol and then reacting the fatty alcohol with ethylene oxide. These non-ionic surfactants can be reacted further with sulphur-containing acids to form another type of anionic surfactant.

How Soaps and Detergents Work
These types of energy interact and should be in proper balance. Let's look at how they work together.
Let's assume we have oily, greasy soil on clothing. Water alone will not remove this soil. One important reason is that oil and grease present in soil repel the water molecules.
Now let's add soap or detergent. The surfactant's water-hating end is repelled by water but attracted to the oil in the soil. At the same time, the water-loving end is attracted to the water molecules.
These opposing forces loosen the soil and suspend it in the water. Warm or hot water helps dissolve grease and oil in soil. Washing machine agitation or hand rubbing helps pull the soil free.
Soaps & Detergents: Human Safety
As consumer needs and lifestyles change, and as new manufacturing processes become available, the soap and detergent industry responds with new products. A commitment to safety is a top priority from the time a company begins working on a new product and continues as long as the product is in the marketplace. Companies evaluate the safety of existing cleaning products by talking with consumers, reviewing scientific developments and monitoring product use data that may affect the safety assessment process.

To determine the safety of a cleaning product ingredient, industry scientists evaluate the toxicity of the ingredient. Toxicity is generally defined as any harmful effect of a chemical on a living organism, i.e., a human, an animal, a plant or a microorganism. Since all chemicals, including water (H2O), are toxic under certain conditions of exposure, scientists must consider a number of factors affecting exposure. These include the duration and frequency of exposure to the ingredient; the concentration of the ingredient at the time of exposure; and the route and manner in which the exposure occurs, e.g., eye, skin or ingestion. This information is essential whether assessing the effect on humans, animals, plants or microorganisms.

Because human safety and environmental evaluations consider different types of exposures, they are evaluated by different procedures. The principal steps in the assessment process are, however, the same. They involve: assembling existing data on toxicity and exposure; determining where new information is needed and, if necessary, carrying out appropriate studies; and determining whether predicted exposure levels are below levels that cause significant toxic effects.

This safety evaluation process enables scientists to predict the potential risk, if any, associated with the use of the ingredient or product, and determine if it is safe for consumers and the environment.
Medical science has long confirmed the important relationship between cleanliness and health. The regular use of cleaning products is fundamental to the health of our society and the well-being of its people.

Because cleaning products are part of our everyday lives, it is essential that they not present a significant risk to health. In considering the human safety of an individual ingredient or product, toxicologists (scientists who assess the safety of a chemical) are concerned with the effects from two types of exposures: intended and unintended. Intended exposures occur with use of a cleaning product according to the manufacturer's directions. Unintended exposures can result from misuse, through improper storage or by accidental contact, such as when a liquid detergent is splashed in the eye.

Hazards from these types of exposures are evaluated from information obtained through (short-term) and chronic (long-term) tests and through a review of existing data. Expected exposure routes are considered as part of this evaluation.

Human safety evaluations begin with the specific ingredients and then move on to the whole product. The effects for all ingredients are considered as the product is formulated.

Toxicologists compare the expected exposure to the expected effect during both product manufacture and use. How will workers be exposed in the plant? What is the intended use of the product? Is it to be diluted? Undiluted? Used daily in the home? Weekly in the workplace? Toxicologists also consider the expected effect of an unintended exposure. What is the potential hazard, for example, if a child drinks a product directly from the bottle?

If this human safety evaluation indicates an unacceptable risk, it may be possible to make the risk smaller by changing the manufacturing process; reformulating to reduce or eliminate an ingredient contributing to the toxic effect; or using labelling or a child-resistant closure. If the risk cannot be reduced, the product will not be marketed.

Even though manufacturers formulate cleaning products to ensure that they are safe or 06sftyhave very low risk, human health effects can still result from unintended exposure. To warn consumers about a specific hazard, household cleaning products carry cautionary labelling whenever necessary. For consumers, this is one of the most important features of the label.

Federal regulations govern how precautionary statements related to human safety are used on household cleaning product labels. The regulations require that statements follow a standard format. There is first a "signal word," followed by a short description of the potential hazard. The following chart shows the signal words - CAUTION or WARNING and DANGER - and what they mean:
POISON, which rarely appears on household cleaning products, is the strongest indication of hazard and means that accidental exposure could cause severe medical effects. The term may be found on household lye and on some car care products, such as antifreeze.

Along with the safety evaluation process and cautionary labelling, an extensive consumer education program on the proper use, storage and disposal of cleaning products supports the human safety efforts of the soap and detergent industry. In addition, the industry works closely with poison control centre’s to assure that, should an accidental exposure occur, treatment information is available to health care providers. 

Together, these activities enable consumers to use cleaning products with confidence in both their safety and performance.

Relevant Articles

  1. Basic Soap and Detergent Chemistry - http://togwt1980.blogspot.co.uk/2015/05/basic-soap-and-detergent-chemistry.html
  2.  Using pH Values to Select Detailing Products - http://togwt1980.blogspot.co.uk/2015/04/using-ph-values-to-select-car-care.html
  3. Understanding Base (Alkalinity) - http://togwt1980.blogspot.co.uk/2015/05/understanding-alkalinity.html

I would like to think that these articles become an asset to anyone who is new to detailing and to professionals alike, as well as industry experts who seek to advance their knowledge.

I hope the above article was informative. By having some understanding of the ‘What’ and ‘Why’ as well as the ‘How’ along with a little science to help you understand how the chemicals we use react, you can achieve the results you desire.

I would appreciate it if you would share this article as it helps other detailers further their knowledge.
Questions and/ or constructive comments are always appreciated.


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