1 slide
2 slide
Synthetic detergents– these are sodium salts of acidic esters of higher alcohols and sulfuric acid
3 slide
History of creation The first SMS appeared only in 1916. The invention of the German chemist Fritz Ponter was intended only for industrial use. Household SMS have been issued since 1935, when they became less harmful to the skin of the hands. Since then, a number of synthetic detergents for specific purposes have been developed, and their production is the most important industry. chemical industry.
4 slide
Consumption About 70% of the SMS consumed by the population is spent on general "heavy" washing, which is done every 3-7 days, during which bed, table and underwear are washed, most often in washing machines. About 20% of the SMC is spent on the "light" washing of lightly soiled items made of thin fabrics by hand in warm water. SMS for easy washing should not irritate the skin of the hands, should create abundant foam and wash well at a water temperature of + 25-45 ° C.
5 slide
Soap Despite the fact that the era of synthetic detergents has arrived, soap is still recommended for hand washing items made from cotton and linen fabrics.
6 slide
Soap Laundry solid soap is a mixture of sodium salts of natural and synthetic fatty acids. Depending on the processing method, solid laundry soap is divided into sawed soap (ground on rollers), containing 72% sodium salts of fatty acids, and regular soap, containing 60 and 70% sodium salts of fatty acids. Sawed soap has a light yellow color, 70% regular soap is yellow and dark yellow, 60% is dark brown and is used mainly for technical purposes.
7 slide
8 slide
Soap powders, granules, and shavings are made mechanically from solid laundry soap in small volumes.
Slide 9
Components of synthetic detergents, or why do they wash away dirt? in the XVIII – 19th centuries It has been proven that soap cleanses because it is a surfactant. It is known that underwear worn for more than a week increases its weight by almost 5%: so much dirt accumulates on it. When washing, it is necessary that the dirt passes from the fabric into the washing solution, into the water. But many contaminants do not dissolve in water. How can you “tear off” poorly wetted dirt particles from the fiber, keep them in solution and prevent them from re-settling on the fabric? Surfactants are used to wet fabric and particles of contaminants, disperse and emulsify them.
10 slide
What are surfactants? What is their role in the washing process? To prevent re-contamination of laundry, special anti-resorbents are added to detergents.
11 slide
What kind of water do you have? At home, you can determine whether your water is hard or soft. To do this, crushed soap is dissolved in hot water: if after cooling the solution remains clear, the water is soft; the solution in hard water becomes covered with a film when cooled. You can also determine the hardness of the water by trying to whip up soap foam: it does not form in hard water. When washing in hard water, more detergent must be added to the washing solution than indicated on the package.
12 slide
To bind hardness salts, special additives are introduced into the SMS composition: polyphosphates, silicates, soda ash, and some other salts. When washing with laundry soap, these additives must be added to the washing solution yourself. Therefore, the advantage of CMC is that its calcium salts are water soluble. Therefore, unlike ordinary soap, they do not lose their cleaning effect even in hard water.
Slide 13
Detergents also contain alkaline additives (soda ash), which contribute to the destruction of fatty contaminants. Chemical bleaches are added to some cotton and linen detergents. At temperatures above 65°C, this compound releases oxygen, which discolors and oxidizes organic compounds, while disinfecting the product.
Slide 14
To remove contamination of protein origin (blood, milk, sauces, eggs), there are special detergents containing enzymes - substances of biological origin that destroy proteins at a temperature not exceeding 40 ° C. After soaking soiled laundry in detergent solutions containing enzymes, protein soils are more easily removed during subsequent washing. The presence of enzymes in detergents is always reported on the packaging in the name of the detergent with the prefix "bio".
15 slide
Attention! These products are intended for washing products made from linen, cotton, artificial and synthetic fibers. They cannot be used for washing wool and silk fabrics - along with protein stains, the fabric itself can be eaten. It must be remembered that elevated (above 60°C) temperatures kill enzymes, so you should not soak clothes or wash them in hot water.
16 slide
Synthetic detergents Thus, surfactants, alkaline additives, chemical bleaches and enzymes are the main substances that break down dirt and remove it from the fabric, i.e. the main components of modern SMS.
Slide 17
Additives To make laundry look snow-white and dyed items look bright, optical brighteners are added to detergents - fluorescent substances that settle on the fabric during washing, but do not destroy it. To ensure that washed clothes have a pleasant smell, perfumes are added to all detergents. Some substances contribute to the formation of abundant foam in the cleaning solution; they are included in detergents intended primarily for hand washing.
Slide 19
Laundry The word “automatic” (“Lotus-automatic”) is added to the name of domestic detergents intended for washing in washing machines, but they can also be washed by hand. Coming on sale detergents of various properties, purpose, can be powdered, liquid, in the form of pastes. From the variety of these tools, you need to choose what suits you best. And one more thing: carefully read everything that is written on the package, and follow these recommendations when washing!
Slide 1
Synthetic detergents
Slide 3
Laundry soap.
Laundry solid soap is a mixture of sodium salts of natural and synthetic fatty acids. Depending on the processing method, solid laundry soap is divided into sawn (ground on rollers), containing 72% sodium salts of fatty acids, and ordinary, containing 60 and 70% sodium salts of fatty acids. Peeled soap has a light yellow color, 70% ordinary soap is yellow and dark yellow, 60%, obtained on the basis of fatty raw materials with the addition of naphthenic acids, is dark brown (used mainly for technical purposes).
Slide 4
From solid laundry soap
Mechanically Soap powders, granules, and shavings are produced in small quantities. So, to obtain a powder, a mixture of soap and soda is sprayed in a cold air environment.
Slide 5
Detergents
They also contain alkaline additives (soda ash), which help destroy fatty contaminants. Some cotton and linen laundry detergents contain chemical bleaches. At temperatures above 65°C, this compound releases oxygen, which discolors and oxidizes organic compounds, while simultaneously disinfecting the product.
Slide 6
Washing pastes
Washing pastes do not generate dust and are very compact. They sometimes contain surfactants that, for a number of technological reasons, cannot be added to powders. The paste is more gentle on the skin of the hands. However, they dissolve in water more slowly and contain 1.5–2 times less tripolyphosphates than powders. Therefore, they can only be washed in relatively soft water.
Slide 7
Liquid detergents
Liquid detergents have all the advantages of both powder and paste detergents. Housewives whose skin is sensitive to the effects of detergents need to choose a product that does not cause irritation and try to use it constantly. In addition, you should not hand wash SMS intended for cotton and linen fabrics, as they contain many alkaline additives that are bad for the skin, and products containing enzymes.
Slide 8
Universal detergents
It is best to use universal SMS containing alkaline additives in smaller quantities. All-purpose detergents can be used to wash all types of fabrics, but not very dirty ones. Thin synthetic, wool and silk fabrics are still best washed with liquid detergents.
Slide 9
Not last on the list household chemicals occupied by washing powders.
Washing is the most labor-intensive process in our everyday life. And assistants in washing are surfactants (surfactants).
Slide 10
Advantages and disadvantages of powders
The advantages of powders are obvious - they quickly dissolve in water, they can be washed in water of any hardness due to the high content of tripolyphosphates (or their substitutes), many powders contain two or more surfactants, which significantly improves their quality. However, powders generate dust when dosing, and some people do not tolerate this dust well, which irritates the respiratory system. In addition, powders are more difficult to dose.
Slide 12
1) obtaining a monoester of sulfuric acid and a higher alcohol (for example, cetyl) C16H33OH + H2SO4 → cetyl conc. alcohol sulfuric acid → C16H33O-SO2-OH + H2O cetylsulfuric acid
Main stages of surfactant production.
slide 13
2) neutralization of the resulting compound with alkali C16H33O-SO2-OH + NaOH → → C16H33O-SO2-ONa + H2O sodium salt of cetylsulfuric acid
Slide 14
In general, the production of surfactants comes down to the following steps technological process:
slide 15
have 10 times greater cleaning power than soap, because... the acidic residue of sulfuric acid is better sorbed by pollution particles; 2) are not afraid of hard and even sea water, because... calcium salts of alkyl sulfuric acid are soluble in water.
Characteristics of surfactants used in SMS:
Slide 16
4. Components of washing powders and their functions.
Phosphates - reduce water hardness and increase washing efficiency. Polymers – prevent resorption. Silicates – additionally protect against corrosion. Sodium perborate – whitens. Optical brightener - masks stains. Enzymes - help break down protein and fat stains on clothes.
Slide 17
Foam release
The cleaning ability of modern SMS is not determined by the abundance of foam. Moreover, there are surfactants that do not produce foam at all and yet are excellent at removing dirt. In practice, foam is only needed when hand washing items made of thin fabric, knitted items and some others, which are washed without wetting too much so that they do not lose shape when drying. Abundant and persistent foam in washing solutions greatly complicates washing in washing machines. Firstly, because of the foam, the mechanical effect on the fabric necessary to remove dirt is reduced, and secondly, with abundant foam, the washing solution can overflow. Therefore, low-foaming products containing foam stabilizers are produced for washing in washing machines. When washing with such detergents, the amount of foam is small and, most importantly, depends little on temperature (and as you know, when using many conventional detergents, the higher the temperature of the washing solution, the more foam there is).
Slide 18
5. Impact of SMS on the environment and the human body.
- Surfactants negatively affect the quality of underground drinking water and the very purifying ability of reservoirs, on the flora and fauna that use this water - aqueous solutions of surfactants produce persistent foam, preventing aeration and thereby worsening the biochemical purification ability of reservoirs, - aqueous solutions of surfactants increase the corrosion of metals, - penetrating into the body, surfactants can cause severe immunity disorders, the development of allergies, damage to the brain, liver, kidneys, lungs, they contribute to the occurrence of malignant tumors.
!
Surfactants are among the most common pollutants of objects environment, first of all, water resources:
Slide 19
!
Getting after washing along with wastewater into water bodies, phosphates are taken to act as fertilizers. Algae begin to grow with incredible force. This leads not only to clogging of reservoirs, but also to a deficiency of water and oxygen, and, consequently, to the death of aquatic organisms.
IN washing powders In addition to surfactants, phosphates are used. In the West, more than 10 years ago they stopped using powders containing phosphate additives.
Slide 20
ATTENTION!!!
Carefully read everything written on the package and follow these recommendations when washing.
Slide 2
CH2-OH | CH-OH | CH2-OH CH2-O-CO-C15H31 | CH-O-CO-C15H31 | CH2-O-CO-C15H31 C17H35СООNa CH3CH2COOCH3 Find the soap formula among the proposed formulas.
Slide 3
Remember what disadvantages of soap we talked about earlier? What types of stains are there on clothes? When did people start using soap for their needs?
Slide 4
The first SMS appeared only in 1916. The invention of the German chemist Fritz Ponter was intended only for industrial use. Household SMS have been issued since 1935, when they became less harmful to the skin of the hands. 1. The concept of SMS and the washing process. Since then, a number of narrow-purpose SMCs have been developed, and their production is the most important branch of the chemical industry.
Slide 5
Slide 6
Not the last place in the list of household chemicals is occupied by washing powders. Washing is the most labor-intensive process in our everyday life. And assistants in washing are surfactants (surfactants).
Slide 7
Surfactants are organic compounds containing in molecules two groups with opposite properties at the same time: polar (hydrophilic) and non-polar (hydrophobic).
Slide 8
separation of dirt particles from the surface being cleaned, transfer of water-insoluble dirt particles into solution, retention of these floating particles in the cleaning solution, i.e. preventing resorption. The washing process comes down to 3 stages:
Slide 9
The first and second washing stages provide surfactants. The most effective surfactants include alkyl sulfates - these are sodium salts of sulfuric acid esters with higher alcohols RO-SO2-ONa, where R is a saturated hydrocarbon radical with 8-18 carbon atoms.
Slide 10
1) obtaining a monoester of sulfuric acid and a higher alcohol (for example, cetyl) C16H33OH + H2SO4 → cetyl conc. alcohol sulfuric acid →C16H33O-SO2-OH + H2O cetylsulfuric acid 2. Main stages of surfactant production.
Slide 11
2) neutralization of the resulting compound with alkali C16H33O-SO2-OH+NaOH→ →C16H33O-SO2-ONa + H2O sodium salt of cetylsulfuric acid
Slide 12
In general, the production of surfactants comes down to the following stages of the technological process:
slide 13
3. Mechanism of action of surfactants. The hydrophobic tail binds to dirt particles. The hydrophilic “head” clings to water, reducing its surface tension, thereby helping the water better wet the surface being washed and tear off particles of contaminants.
Slide 14
Laboratory experience. Purpose of the experiment: to study the interaction of hard water with solutions of soap and washing powder. In front of you are 2 test tubes: one contains a soap solution, the other contains a solution of washing powder, and the flask contains hard water. Pour a small amount of hard water into the soap and SMS solutions, cap and shake. What are you observing? How can this be explained?
slide 15
1) have 10 times greater cleaning power than soap, because... the acidic residue of sulfuric acid is better sorbed by pollution particles, 2) they are not afraid of hard and even sea water, because calcium salts of alkyl sulfuric acid are soluble in water. Characteristics of surfactants used in SMS:
Slide 16
4. Components of washing powders and their functions. Phosphates - reduce water hardness and increase washing efficiency. Polymers – prevent resorption. Silicates – additionally protect against corrosion. Sodium perborate – whitens. Optical brightener - masks stains. Enzymes - help break down protein and fat stains on clothes.
Slide 17
5. Impact of SMS on the environment and the human body. - Surfactants negatively affect the quality of underground drinking water and the very purifying ability of reservoirs, the flora and fauna that use this water, - aqueous solutions of surfactants produce persistent foam, preventing aeration and thereby worsening the biochemical purification ability of reservoirs, - aqueous solutions of surfactants increase corrosion of metals, - penetrating into the body, surfactants can cause severe immunity disorders, the development of allergies, damage to the brain, liver, kidneys, lungs, they contribute to the occurrence of malignant tumors. ! Surfactants are one of the most common pollutants of the environment, primarily water resources:
Slide 18
For example, in Germany, Italy, Austria, Norway, Switzerland and the Netherlands, the use of phosphate powders is prohibited by law. In France, Great Britain, and Spain, the phosphate content in SMS is strictly regulated (no more than 12%). ! When phosphates get into water bodies after washing along with wastewater, they act as fertilizers. Algae begin to grow with incredible force. This leads not only to clogging of reservoirs, but also to a deficiency of water and oxygen, and, consequently, to the death of aquatic organisms. In addition to surfactants, washing powders use phosphates. In the West, more than 10 years ago they stopped using powders containing phosphate additives.
View all slides
Modular lesson on the topic: “Soap. Synthetic detergents.
- Performed by Kuznetsova E.V. Chemistry teacher GBPOU VO VAT named after V.P. Chkalova
Lesson topic:
Goals:
Soap. Synthetic detergents.
- study the composition, preparation, properties of soap and synthetic detergents ;
- predict the detergent properties of soap ;
- update knowledge about water hardness ;
- be able to determine the environment of a soap solution, conduct a practical analysis of water hardness.
History of soap.
Humanity has been using soap since time immemorial: the history of soap making goes back at least 6 thousand years.
W.E. – 2 “Knowledge updating.” History of soap.
- The Roman scientist and politician Pliny the Elder claims that even the ancient Gauls (who inhabited the territory of modern France) and the Germans knew about making soap. According to his testimony, these wild tribes made a kind of miraculous ointment from the tallow and ash of the beech tree, which was used to clean and dye hair, as well as to treat skin diseases.
W.E. – 2 “Knowledge updating.” History of soap.
Legend has it that the Latin word lat. sapo(soap) comes from the name of Mount Sapo in ancient Rome, where sacrifices were made to the gods.
W.E. – 2 “Knowledge updating.” History of soap.
Animal fat released when the victim was burned accumulated and mixed with the wood ash of the fire. The resulting mass was washed away by rain into the clayey soil of the banks of the Tiber River, where residents washed clothes and, naturally, human observation did not miss the fact that thanks to this mixture, clothes were washed much easier.
W.E. – 2 “Knowledge updating.” History of soap.
- From the 13th century Soap making flourishes in France and England. The attitude to this craft was the most serious. In 1399 in England, King Henry IV founded an order whose special privilege was considered to be washing in a bath with soap.
W.E. – 2 “Knowledge updating.” History of soap.
- In 1808, the French chemist Michel Eugene Chevreul (1786−1889), at the request of the owners of a textile factory, established the composition of soap. As a result of the analysis, it turned out that soap is the sodium salt of a higher fatty (carboxylic) acid.
W.E. – 2 “Knowledge updating.” History of soap.
- Many centuries ago, soap-making arose in Rus', where since ancient times people have been distinguished by neatness, the habit of regular washing in a bathhouse, a steam room. Soap factories appeared.
W.E. – 2 “Knowledge updating.”
What causes water hardness?
http://ru.wikipedia.org/wiki/%C6%B8%F1%F2%EA%EE%F1%F2%FC_%E2%EE%E4%FB
Check yourself!!! .
Water hardness is due to the high concentration of ions in water Ca 2+i Mg 2+
Criteria for evaluation:
for the correct answer - 1 point .
Using text "Soaps and synthetic detergents" http://www.krugosvet.ru/enc/nauka_i_tehnika/tehnologiya_i_promyshlennost/MOYUSHCHIE_SREDSTVA.html
and answer the following questions orally:
- What is the composition of the soap?
- How does the cleaning power of solid and liquid soap differ?
- What are synthetic detergents?
- How can you make soap?
Criteria for evaluation: for the correct answer - 1 point
Fill out the table:
Name of detergent.
Solid soap
Receipt
Liquid soap
Cleaning power
Synthetic detergent
W.E. – 3 “Learning new material.”
Check yourself!!! Evaluation criteria: (each line -1 point, maximum - 3 points)
Name of detergent.
Formula
Solid soap.
C 17 H 35 COONa C 15 H 31 COONa
Receipt
Liquid soap.
Synthetic detergent.
Cleaning power
CH 2 -O-CO-C 15 H 31
CH-O-CO-C 15 H 31 +3NaOH
CH 2 -O-CO-C 15 H 31
CH-OH +3 C 15 H 31 COONa
CH 2 -OH sodium stearate
C 16 H 33 O - SO 2 - ONa
Loses cleaning ability in hard water.
CH 2 -O-CO-C 15 H 31
CH-O-CO-C 15 H 31 +3 K OH
CH 2 -O-CO-C 15 H 31
CH-OH +3 C 15 H 31 COOK
CH 2 -OH potassium palmitate
The cleaning power of liquid soap is better than solid soap.
2 C 17 H 35 COOK + Ca 2+ = (C 17 H 35 COO) 2 Ca + 2K +
C 16 H 33 O - SO 2 - OH + NaOH →
→ C 16 H 33 O - SO 2 - ONa + H 2 O
sodium salt
cetylsulfuric acid
SMS has the best cleaning power compared to soaps, because... calcium salt, for example, cetylsulfuric acid, is soluble.
W.E. – 3 “Learning new material.”
Solve the problem:
Option 1
How much soda ash (in g) will be required to react with 54.4 g of stearic acid and how much (in g) sodium stearate will be formed at 90% yield?
a) 5.3 and 17.2;. b) 7.2 and 27.54;
c) 10.6 and 17.2; d) 58.8g and 52.92g.
Option 2
When 54.4 g of palmitic acid reacted with soda ash, 54.4 g of sodium palmitate was formed. Determine the percentage yield of soap.
a) 86.7% b)74.3%
c) 91.3% d) 69.23%
W.E. – 3 "Learning new material".
Examination.
Option 1 - d)
2C 17 H 35 COOH + Na 2 CO 3 = 2 C 17 H 35 COONa + CO 2 + H 2 O
ν (C 17 H 35 COOH) \u003d 54.4 g / 272 g ∕ mol \u003d 0.2 mol
m theor. (C 17 H 35 COO Na) \u003d 0.2 mol 294 g ∕ mol \u003d 58.8 g
m practical (C 17 H 35 COO Na) \u003d 58.8 g 90% / 100% \u003d 52.92 g
Answer: 58.8g, 52.92g.
Criteria for evaluation:
Option 2 – a)
2C 15 H 31 COOH + Na 2 CO 3 \u003d 2 C 15 H 31 COONa + CO 2 + H 2 O
ν (C 15 H 31 COOH) \u003d 54.4 g / 272 g ∕ mol \u003d 0.4 mol
m theor (C 15 H 31 COOH) \u003d 0.4 mol 158 g ∕ mol \u003d 63.2 g
ω (C 15 H 31 COOH) \u003d 54.4 / 63.2 100% \u003d 86.7%
Answer: 86.7%
the solution of the problem- 2 points maximum 2 points
W.E. – 3 “Learning new material.”
Surfactants - These are organic compounds containing in molecules two groups with opposite properties at the same time:
polar (hydrophilic) and
non-polar (hydrophobic).
W.E. – 3 “Learning new material.”
The washing process is reduced
to ensure 3 stages:
1. Separation of dirt particles from the surface to be cleaned
2. Translation of water-insoluble mud particles
into solution
3. Keeping these floating particles in detergent
solution, i.e. prevention resorption
W.E. – 3 “Learning new material.”
Mechanism of action of surfactants.
Hydrophobic tail binds to dirt particles. Hydrophilic “head” clings to water, reducing its surface tension, thereby helping the water better wet the surface being washed and tear off particles of contaminants.
W.E. - 4
Laboratory experiment No. 1
Determination of the environment of the soap solution.
Laboratory experiment No. 2
Interaction of hard water with solutions of soap and washing powder .
Perform the laboratory experiment according to the instructions, fill in the table.
W.E. - 4 "Consolidation of new material".
- Fill out the table:
№ experience
Observations
Reaction equations
Conclusion
W.E. - 4 "Consolidation of new material".
Self-check!!!
Criteria for evaluation: each experience - 2 points (maximum 4 points)
№ experience
Observations
Litmus paper turns blue
Reaction equations
Conclusion
C 17 H 35 COO N a + H 2 O = C 17 H 35 COOH + N aOH
When hard water is added, a precipitate in the form of flakes is released in the flask with a soap solution, this is not observed with SMS, the solution foams well
The change in litmus color to blue is caused by the presence of OH -- -ions formed as a result of the hydrolysis of soap.
2 C 17 H 35 COONa + Ca 2+ = (C 17 H 35 COO) 2 Ca + 2Na +
Soap loses its washing ability in hard water, because a reaction occurs in the exchange of Na + ions for Ca 2+ or Mg 2+ ions and a water-insoluble precipitate of calcium or magnesium stearate is formed, which precipitates in the form of flakes. Calcium or magnesium salts of sulfuric acid esters with higher alcohols are soluble in water.
UE – 5 Knowledge control
Take the test!
https://docs.google.com/a/i-dist.ru/spreadsheet/viewform?formkey=dEhkSTRfOVZ0UnJmajJOWHRuYXgwQ1E6MQ
Evaluation criteria
every correct answer - 1 point. (maximum 5 points)
W.E. – 6 “Summing up the lesson”
1. Read the lesson objectives (LE-0). 2. Do you think that you have achieved the objectives of the lesson? 3. How would you rate the results of your work in the lesson?
Please rate in the "self-rating" column:
a) I understand everything, I can explain this material
to another (5 points) b) I understood everything myself, but I don’t undertake to explain to another
(4 points) c) for a complete understanding, I need to repeat
topic (3 points) d) I did not understand anything (2 points).
Calculate the scores received in the lesson.
Give yourself a rating.
W.E. – 6 “Homework”
assessments
exercise
Make a crossword on the topic “Fats. Soap. SMS." (10-15 words)
Lesson summary
Creative task :
prepare a report on the topic "Environmental aspects of the use of surfactants"
Slide presentation
Slide text: Lesson objectives: To provide an understanding of SMS and surfactants, To consider their production and mechanism of action during washing, To analyze the effect of surfactants and phosphates on the environment and human health.
Slide text: CH2-OH | CH-OH | CH2-OH CH2-O-CO-C15H31 | CH-O-CO-C15H31 | CH2-O-CO-C15H31 C17H35СООNa CH3CH2COOCH3 Find the soap formula among the proposed formulas.
Slide text: Remember what disadvantages of soap we talked about earlier? What types of stains are there on clothes? When did people start using soap for their needs?
Slide text: The first SMS appeared only in 1916. The invention of the German chemist Fritz Ponter was intended only for industrial use. Household SMS have been issued since 1935, when they became less harmful to the skin of the hands. 1. The concept of SMS and the washing process. Since then, a number of narrow-purpose SMCs have been developed, and their production is the most important branch of the chemical industry.
Slide text:
Slide text: Washing powders occupy not the last place in the list of household chemicals. Washing is the most labor-intensive process in our everyday life. And assistants in washing are surfactants (surfactants).
Slide text: these are organic compounds containing in their molecules two groups with opposite properties at the same time: polar (hydrophilic) and non-polar (hydrophobic).
Slide text: separation of dirt particles from the surface being cleaned, transfer of water-insoluble dirt particles into solution, retention of these floating particles in the cleaning solution, i.e. preventing resorption. The washing process comes down to 3 stages:
Slide text: The first and second washing stages provide surfactants. The most effective surfactants include alkyl sulfates - these are sodium salts of sulfuric acid esters with higher alcohols RO-SO2-ONa, where R is a saturated hydrocarbon radical with 8-18 carbon atoms.
Slide No. 10
Slide text: 1) obtaining a monoester of sulfuric acid and a higher alcohol (for example, cetyl) C16H33OH + H2SO4 → cetyl conc. alcohol sulfuric acid → C16H33O-SO2-OH + H2O cetylsulfuric acid 2. Main stages of surfactant production.
Slide No. 11
Slide text: 2) neutralization of the resulting compound with alkali C16H33O-SO2-OH + NaOH → → C16H33O-SO2-ONa + H2O sodium salt of cetylsulfuric acid
Slide No. 12
Slide text: In general, the production of surfactants comes down to the following stages of the technological process:
Slide No. 13
Slide text: 3. Mechanism of action of surfactants. The hydrophobic tail binds to dirt particles. The hydrophilic “head” clings to water, reducing its surface tension, thereby helping the water better wet the surface being washed and tear off particles of contaminants.
Slide No. 14
Slide text: Laboratory experience. Purpose of the experiment: to study the interaction of hard water with solutions of soap and washing powder. In front of you are 2 test tubes: one contains a soap solution, the other contains a solution of washing powder, and the flask contains hard water. Pour a small amount of hard water into the soap and SMS solutions, cap and shake. What are you observing? How can this be explained?
Slide No. 15
Slide text: 1) have 10 times greater cleaning power than soap, because... the acidic residue of sulfuric acid is better sorbed by pollution particles, 2) they are not afraid of hard and even sea water, because calcium salts of alkyl sulfuric acid are soluble in water. Characteristics of surfactants used in SMS:
Slide No. 16
Slide text: 4. Components of washing powders and their functions. Phosphates - reduce water hardness and increase washing efficiency. Polymers – prevent resorption. Silicates – additionally protect against corrosion. Sodium perborate – whitens. Optical brightener - masks stains. Enzymes - help break down protein and fat stains on clothes.
Slide No. 17
Slide text: 5. Impact of SMS on the environment and the human body. - Surfactants negatively affect the quality of underground drinking water and the very purifying ability of reservoirs, the flora and fauna that use this water, - aqueous solutions of surfactants produce persistent foam, preventing aeration and thereby worsening the biochemical purification ability of reservoirs, - aqueous solutions of surfactants increase corrosion of metals, - penetrating into the body, surfactants can cause severe immunity disorders, the development of allergies, damage to the brain, liver, kidneys, lungs, they contribute to the occurrence of malignant tumors. Surfactants are one of the most common pollutants of the environment, primarily water resources:
Slide #18
Slide text: For example, in Germany, Italy, Austria, Norway, Switzerland and the Netherlands, the use of phosphate powders is prohibited by law. In France, Great Britain, and Spain, the phosphate content in SMS is strictly regulated (no more than 12%). When phosphates get into water bodies after washing along with wastewater, they act as fertilizers. Algae begin to grow with incredible force. This leads not only to clogging of reservoirs, but also to a deficiency of water and oxygen, and, consequently, to the death of aquatic organisms. In addition to surfactants, washing powders use phosphates. In the West, more than 10 years ago they stopped using powders containing phosphate additives.
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