HYDROLYSING ESTERS

This describes ways of hydrolyzing esters - splitting them into carboxylic acids (or their salts) and alcohols by the action of water, dilute acid or dilute alkali. It starts by looking at the hydrolysis of simple esters like ethyl ethanoate, and goes on to look at hydrolyzing bigger, more complicated ones to make soap. Hydrolyzing simple esters What is hydrolysis? Technically, hydrolysis is a reaction with water. That is exactly what happens when esters are hydrolyzed by water or by dilute acids such as dilute hydrochloric acid. The alkaline hydrolysis of esters actually involves reaction with hydroxide ions, but the overall result is so similar that it is lumped together with the other two. Hydrolysis using water or dilute acid The reaction with pure water is so slow that it is never used. The reaction is catalyzed by dilute acid, and so the ester is heated under reflux with a dilute acid like dilute hydrochloric acid or dilute sulphuric acid. Here are two simple examples of hydrolysis using an acid catalyst. First, hydrolyzing ethyl ethanoate: . . . and then hydrolyzing methyl propanoate: Notice that the reactions are reversible. To make the hydrolysis as complete as possible, you would have to use an excess of water. The water comes from the dilute acid, and so you would mix the ester with an excess of dilute acid.
Hydrolysis using dilute alkali This is the usual way of hydrolyzing esters. The ester is heated under reflux with a dilute alkali like sodium hydroxide solution. There are two big advantages of doing this rather than using a dilute acid. The reactions are one-way rather than reversible, and the products are easier to separate. Taking the same esters as above, but using sodium hydroxide solution rather than a dilute acid: First, hydrolyzing ethyl ethanoate using sodium hydroxide solution: . . . and then hydrolyzing methyl propanoate in the same way: Notice that you get the sodium salt formed rather than the carboxylic acid itself. This mixture is relatively easy to separate. Provided you use an excess of sodium hydroxide solution, there won't be any ester left - so you don't have to worry about that. The alcohol formed can be distilled off. That's easy! If you want the acid rather than its salt, all you have to do is to add an excess of a strong acid like dilute hydrochloric acid or dilute sulphuric acid to the solution left after the first distillation. If you do this, the mixture is flooded with hydrogen ions. These are picked up by the ethanoate ions (or propanoate ions or whatever) present in the salts to make ethanoic acid (or propanoic acid, etc). Because these are weak acids, once they combine with the hydrogen ions, they tend to stay combined. The carboxylic acid can now be distilled off. Hydrolyzing complicated esters to make soap This next bit deals with the alkaline hydrolysis (using sodium hydroxide solution) of the big esters found in animal and vegetable fats and oils.
If the large esters present in animal or vegetable fats and oils are heated with concentrated sodium hydroxide solution exactly the same reaction happens as with the simple esters. A salt of a carboxylic acid is formed - in this case, the sodium salt of a big acid such as octadecanoic acid (stearic acid). These salts are the important ingredients of soap - the ones that do the cleaning. An alcohol is also produced - in this case, the more complicated alcohol, propane-1,2,3-triol (glycerol). Because of its relationship with soap making, the alkaline hydrolysis of esters is sometimes known as saponification.

Different Dyes

1-Acid Levelling Dyes
We offer low-foaming acid levelling dyes that is used in diverse range of industries for dying. These acid levelling dyes are available with good dispersing and leveling properties for dyeing silk and nylon in quick procedure. The types of acid levelling dyes are as follows:more...
Amritlal Chemaux Pvt Ltd.
View CatalogContact Now

2-Leather Dyes
We also offer leather dyes. These dyes offer bright colors and excellent fastness properties. Offering different type of finishes and color tones, our leather dyes are mostly used in the furniture industry. They also give a bright shades and excellent leveling and is also sold in bulk. more...
Sr Speciality Chemicals
View CatalogContact Now

3-Liquid Acrylic Dyes
We offer a comprehensive variety of acrylic dyes that are exclusively used in textile industries for coloring or dyeing blankets, carpets, knitted goods, decorative fabrics and leather products. Characterized by their tinctorial power, outstanding brightness and excellent color fastness, we supply acrylic dyes available in wide number of colors and its shades. With this we also supply a blend of these sheds in different combinations for a particular shade. more...
Arbuda Plastochem Private Limited
View CatalogContact Now

4-Reactive Dyes
We offer reactive dyes. Reactive dyes a chromophore contains a substituent taht is activated and allowed to directly react to the surface of the substrate. Reactive dyes are available in following range :(a) Reactive cold brand :- dyes also called M brand dyes are highly reactive requiring comparatively Milder condition in dye fixation. Dyeing can be done at normal room temperature (about 25 to 30 degree C) by using soda ash. Reactive M Brand is applicable to cellulosie textile by batch wise and continues method in convenient textile machinery like open vat.(b) Reactive HE Series :- (High Exhaust series dyes) He Dyes are reactive dyes for cellulosie material and are designed to give high fixation by exhaust dyeing method, when applied at temperature 75 to 90 Degree. HE Dyes are suitable for cotton and other cellulosie material. These Dyes process significantly higher exhaustion and fixation efficiency which result in appreciable more...
A.K. Chemi Dyes Enterprises
View CatalogContact Now

5-Fabric Reactive Dye
Our wide range of saicron He brand fabric reactive dyes are chemically bonded to the textile fibers, which help increasing the color stability and wash ability of the fabric. This makes the reactive dyeing of cotton the most widespread process in the textile process.
Shreya Aniline Industries Pvt. Ltd.
View CatalogContact Now

6-oron Ternary - D
We offer an array of foron ternary – D, which are known for their accurate composition and superior quality. Available in various colors and tints, these are formulated using the best grade chemicals and other materials. We provide these at highly competitive prices to the clients. more...
Riddhi Siddhi Trading Co
View CatalogContact Now

7-Leather Natural Dyes
We offer a wide array of premium quality leather natural dyes that can be used for dyeing different types of leather products. Enhancing the look of the leather product together with increasing its life, our range of leather natural dyes are available at the most reasonable price, Our leather natural dyes are available in variety of shades such as more...
Advent Dyestuffs And Chemicals Pvt. Ltd.
View CatalogContact Now

8-Brown Acid Dyes
Catering to the demands of dyeing applications, our range of brown acid dye is in huge demand. Formulated as per various industrial standards, these are offered as self shades to mixtures as per the customer’s requirements. more...
Lotus Enterprise, Mumbai
View CatalogContact Now

9-Yellow Reactive H Dyes
We offer our clients yellow reactive H dyes which are been used for the textile dying applications. The various specifications of the dye is been given as below:more...
Navin Chemicals
View CatalogContact Now

10-Spartek Dyes
Made from premium quality raw material, our range of spartek dyes are formulated to cater to the needs of our quality cautious clients. These highly effective dyes are offered to our clients in a wide palette of mild as well as vibrant colors at industry leading prices. Our spartek dyes are made from fine quality chemicals that make them user friendly and are proved to be effective on all types of fabrics. more...
Bhatia Colour Co.
View CatalogContact Now

11-Disperse Dyes
We specialize in formulating the finest quality of disperse dyes that are widely demanded in the domestic and international markets. These disperse dyes are developed using superior quality chemicals and other raw material and are offered in a plethora of colors and their color tints. Our range of disperse dyes can be availed in a multitude of tints of yellow, red and blue. more...
Bhatia Colour Co.
View CatalogContact Now

12-Basic Dyes
Basic dyes are widely used in textile and paper industries. Basic dyes offered by us are used mainly in colouring jute and jute products. These basic dyes are generally used to produce bright and deep shades. We supply a wide range of basic dyes which includes: more...
Arbuda Plastochem Private Limited
View CatalogContact Now

13-Magenta And Violet Reactive M Dyes
We offer high grade magenta and violet reactive dyes, which have got wide eminence in the textile industry. These dyes are brilliant with high light fastness on cellulosic fibers & fabric.more...
Navin Chemicals
View CatalogContact Now

14-Drimalan
We offer qualitative range of Drimalan dyes that are effective for cellulosic materials and their blends, synthetic fibers and various other fibers. These are formulated using the best possible compositions of pure chemicals. We offer these dyes in bulk quantities and at most reasonable prices. more...
Riddhi Siddhi Trading Co
View CatalogContact Now

15-Industrial Dyes
Our wide range of industrial dyes are used in various industries like textiles, garments, plastic etc. These industrial powder dyes are applied in an aqueous solution, and are used in dyeing of fabrics. Prepared from qualitative raw material, our finished dyes produces fast colors in fibers placed directly in the dye solutions. The dyes are available in both liquid and powder form and are packed in airtight packets.
Shreya Aniline Industries Pvt. Ltd.
View CatalogContact Now

16-Yarn Dyes
Used for dyeing variety of fabrics including wool, silk, nylon and more, our range of yarn dyes ensures a uniform coloring and processing of fabrics. Our yarn dyes form a strong covalent bond with different fabrics and provide a permanent color to them. Our range of yarn dyes can also be customized as per the requirements of our clients. Our yarn dyes have the following applications:Against Acid M of Multinational Co. more...
Advent Dyestuffs And Chemicals Pvt. Ltd.
View CatalogContact Now

17-Acid Leather Dyes
We offer acid leather dyes that are of low-foaming level, that can be easily used for any kind of leather. Its diverse range of acid leather dyes includes -more...
Amritlal Chemaux Pvt Ltd.
View CatalogContact Now

18-Basic Dyes
Basic dyes are water soluble cationic dyes taht are mainly applied to acrylic fibers but find some use for wool and silk. Basic dyes has bright brilliant shade and excellent value. These basic dyes gives supers results on : more...
A.K. Chemi Dyes Enterprises
View CatalogContact Now

Textile Dyeing
Offering colored textile dyeing of clothes.
Rubee Dyeing Company
Contact Now

Reactive Dye 2

Reactive Dye
Reactive dyes are a class of highly coloured organic substances, primarily used for tinting textiles, that attach themselves to their substrates by a chemical reaction that forms a covalent bond between the molecule of dye and that of the fibre. The dyestuff thus becomes a part of the fibre and is much less likely to be removed by washing than are dyestuffs that adhere by adsorption. The first fibre reactive dyes were designed for cellulose fibres, and they are still used mostly in this way. There are also commercially available fibre reactive dyes for protein and polyamide fibres. In theory, fibre reactive dyes have been developed for other fibres, but these are not yet practical commercially. The dyes contain a reactive group that, when applied to a fibre in a weakly alkaline dyebath, form a chemical bond with the fibre. Reactive dyes can also be used to dye wool and nylon, in the latter case they are applied under weakly acidic conditions. more...
Ghosh Dyechem
View CatalogContact Now