Mixing Unit in Blowroom

The Integrated Mixer MX-I, coupled with a CLEANOMAT Cleaner CL-C3."

The Universal Mixer MX-U is ideal for feeding two parallel installation.

The Dosing Opener FD-S buffers small material amounts and releases them in doses.

The optimal solution for every mixing task

Truetzschler mixing systems offer individual solutions for every spinning mill and every task in the area of single component staple fibre mixing:

• Improved economic efficiency due to direct coupling of cleaner and mixer
• Tailor-made mixer sizes
• Maximum homogeneity due to controlled, reproducible mixing
• Uniform product appearance by optimising the mixture
• Requirement-specific feeding with 6 or 10 trunks
• The already outstanding blending can be further increased by two mixers arranged in series (tandem mixing).

Two powerful trunk mixers for maximum homogeneity

Integrated Mixer MX-I

• Ideal for compact installations:
  Direct coupling of mixer with a cleaner or opener
• Compact

Universal Mixer MX-U

• Ideal for feeding two parallel cleaners: Material suctioned off by downstream machine
• Low maintenance
• Direct suction of mixing duct
• Closed air circulation

Dosing Opener FD-S

• For uniform material flow
• Serves as buffer for downstream machines

CLEANING ZONE BY TRUETZSCHLER

Pre-Cleaner CL-P

Universal Cleaner CL-U

Cleaner CL-C 1

Cleaner CL-C 3

Universal Opener TO-U

Tuftomat TO-T1

Fine Opener TO-C

Clear line towards success

Specialists for clean work

Our solutions for economic processing of cotton and man-made fibres in the short staple sector: Cleaner CLEANOMAT and Opener TUFTOMAT. The cleaners of the CLEANOMAT system ensure a high degree of cleaning at minimum fibre loss for these components. The investment in these technologies pays off within a short time due to increased yield of good fibres.

Tailor-made opener range

In addition to the economic efficiency, the CLEANOMAT system also impresses by the product quality at the end of the process. This, among other things, is due to the optional, infinitely variable drives. This perfection continues with the TUFTOMAT system when opening the fibres. Whether processing polyester, acrylic, polypropylene, viscose or bleached cotton: For each application there is a tailor-made solution.

The system components

CLEANOMAT Pre-Cleaner CL-P

• Gentle cleaning from the start
• Removal of coarse impurities from the raw material

CLEANOMAT Universal Cleaner CL-U

• Unparalleled efficiency
• WASTECONTROL in series
• Covers all standard applications
• 4-roll feed unit

  

CLEANOMAT Cleaner CL-C1

• Cleaning and opening in one process
• Excellent cleaning (even with long staple cottons)
• 1 Cleaning roll

CLEANOMAT Cleaner CL-C3

• Stand-alone cleaner for medium to severe impurity level in cottons
• In combination with Pre-Cleaner CL-P, it is suited for almost all cottons
• 3 Cleaning rolls The advantages of the CLEANOMAT system
• Maximum cleaning, extremely gentle to the fibres
• Flexible adjustment of cleaning degree
• Perfect adaptation to every cotton
• Very clean machines, even when processing sticky cotton
• Higher yarn quality and improved running behaviour in OE and ring spinning
• Reduced maintenance due to belt drives and maintenance-free motors
• Precision computer control and monitoring

Fibre reinforced composites application in textiles

Fibre reinforced composites application in textiles
A composite material is made by combining two or more materials to give a unique combination of properties one of which is made up of stiff, long fibres, and the other, a binder or 'matrix' which holds the fibres in place. The fibres are strong and stiff relative to the matrix and are generally orthotropic. Composites are a versatile and valuable family of materials that can solve problems of different applications, improve productivity, lower cost and facilitate the introduction of new properties in material. This article deals with fibre-reinforced composites properties and its uses in machine, equipment and apparatus construction, medical technology and tensile behaviour in knitted fabrics. Composites consist of two or more phases that are usually processed separately and then bonded, resulting in properties that are different from those of either of the component materials. Polymer matrix composites generally combine high-strength, high-stiffness fibres (graphite, Kevlar, etc). Composites involve two or more component materials that are generally combined in an attempt to improve material properties such as stiffness, strength, toughness, etc. Fibre-reinforced composites often aim to improve the strength to weight and stiffness to weight ratios (ie, desire lightweight structures that are strong and stiff). Fibres are available in 3 basic forms. Types of composite The three basic types of composites are generally identified as: Particle-reinforced (Aggregates). Fibre-reinforced (Continuous fibre or Chopped fibre). Natural composites (Examples: Wood and Bone). Properties of composite materials Lightweight, high-strength, corrosion resistant, flexibility, low cost, low mass, in aeronautics. Composite materials have six properties giving them an edge over standard materials: Longer life cycle thanks to high fatigue strength, corrosion resistance, improved fire resistance, easier design because of function integration, possibility of complex shapes and lightweight components. Properties of 3D textile composites The plain weft knitted fabric reinforced composite material investigated in this study is assumed to have only reinforcement fibre yarns and polymer matrix. For analysis purposes, a unit cell representing the complete knitted fabric composite is identified. A geometric model is proposed to determine the orientation of yarn in the composite. Outline the procedure for estimating the fibre volume fraction of the composite. The unit cell is divided into four representative volumes, also called a 'crossover model'. The crossover model is further divided into sub-volumes, which are considered as transversely isotropic unidirectional fibre-reinforced composites. A new micro-mechanical model is used to predict all the five independent elastic constants of the unidirectional fibre-reinforced composites. By considering the contributions of both the fibres and net matrix material, the compliance/stiffness matrix of each sub-volume in the material co-ordinate system is calculated using the new formula. This compliance/stiffness matrix of each sub-volume is then transformed to the global co-ordinate system. A volume averaging scheme has been applied to obtain the overall compliance/stiffness matrix of the knitted fabric composite. The effects of fibre content and other parameters of knitted fabric on the elastic properties of the composite material are identified. Application of composites Composite materials have long been utilised in various industries including automotive, heavy truck, aerospace, civil infrastructure, marine and durable goods. Fibres for Conveyor Belt. Fibres-Reinforced Conveyor Belt Application. Pipes, Tanks & Vessels Applications. Composite Pipe Work Application. Joining Technique. Aerospace Application. Aircraft Application. Rocket and Missiles Applications. Marine Application. Tensile Behaviour of Knitted Fabrics Composite. Fibres for conveyor belt These physical and chemical properties of Kevlar fibres allow using it as the reinforcement material for conveyor belts. By using this it is possible to design light and linger conveyor belts. This design feature is a major advantage in applications that require a high modulus, lightweight belt as a replacement to steel cords, thus providing for the use of narrow, fast belts of high-strength, which can be employed efficiently over long distances. The use of these type of belt led to lower manufacturing and installation costs, reduced energy consumption, no sparking and non-flammability giving improved safety, better corrosion, better impact resistance and longer life. Fibre-reinforced conveyor belt application Conveyor belts are flexible composite plates that when interconnected it forms an endless entity and can efficiently transfer bulk materials or parcels from one place to another. Conveyor belt systems are composed of endless belt, pulleys, idlers, electrical motors, counter weight, rigid structure and other accessories. Conveyor belts have to meet rather different requirements, depending on the particular application. The basic properties required include: High strength and flexibility. Low extension in service. Resistance to abrasion. Impact and tearing resistance. Resistance to moisture, oils and chemicals. Typical conveyor belt system. Pipes, tanks and vessels application Fibre-reinforced composites have more number of end applications and significant areas in different fields, one of the applications were composites are being employed for fluid transport and storage. The most important material here is glass reinforced epoxy (GRE), which has been used onshore for both low and high-pressure applications with a wide variety of fluids, including hydrocarbons. The chemical resistance of glass reinforced epoxy and the maximum use of temperature in a particular fluid depends on the type of resin and hardener used. Glass reinforced epoxy tubes are largely immune to the effects of hydrogen sulphide and carbon dioxide. The most damaging chemical component is often water, rather than oil, although some highly aromatic species such as toluene and xylene can be damaging. Composite pipe work application The most successful offshore applications for composites have been in pipework for aqueous liquids. The most important material here is glass reinforced epoxy (GRE), which has been used onshore for both low and high-pressure applications with a wide variety of fluids, including hydrocarbons. By contrast, the main offshore applications have been confined so far to relatively low pressure aqueous services, of the type shown in Figure. The chemical resistance of glass reinforced epoxy tubes and the maximum use temperature in a particular fluid depends on the type of resin and hardener used. Glass reinforced epoxy tubes are largely immune to the effects of hydrogen sulphide and carbon dioxide. The most damaging chemical component is often water, rather than oil, although some highly aromatic species such as toluene and xylene can be damaging. Joining techniques Several joining techniques are used for thermosetting pipes. The lengths of glass reinforced epoxy pipe may be joined to fittings or to each other by; Adhesive bonding. Laminating (butt and wrap joints) or By mechanical means, such as the rubber seal joint or the threaded joints. Adhesively bonded joints may be of the taper-taper, socket and spigot or parallel (Quick-Lock) type. In each case, the socket may be either filament wound or moulded. Alternatively the socket may be directly moulded into the end of a straight length of filament wound pipe. The spigot end of the pipe is prepared by machining or shaving to the required dimensions and shape. For field or on-site joints, special shaving tools are provided for this. The joint is made by coating with adhesive (usually epoxy), assembly and elevated temperature curing using a heating blanket. Joints of this type are very common in the oil industry, both onshore and offshore. Bonding is also used to assemble flanges onto glass reinforced epoxy pipe work for subsequent attachment to other parts of the system. Flange joints are often used where easy disassembly is required. Butt and wrap joints Butt and wrap joints are provided by many pipe manufacturers. Here, the plain pipe ends are brought together, after abrading the outer surface, the joint being made by over-laminating with glass fibre and resin. Although cheaper from a materials viewpoint than adhesive joints, butt and wrap joints are more labour-intensive and difficult to make on-site. Both adhesive and butt and wrap joints, when properly made, provide a generous margin of safety. It has been shown (Cowling et al, 2000) that such joints are highly defect tolerant when assembled according to the correct procedures. The principal means of ensuring integrity is the hydro test, usually carried out at 1.5 times working pressure. Good results have been reported overall with these systems; provided a number of simple rules are followed and responsible personnel have been properly trained. It is also necessary to maintain an auditable chain of responsibility from the pipe manufacturer through to the personnel who carry out the jointing procedure. Rubber seal joint Rubber seal systems are used commonly at lower pressures because they provide for rapid assembly (and disassembly). The hydraulic seal is achieved by means of one or more rubber O-rings inserted into grooves in the male pipe end. The axial load is supported by a cylindrical key, often of nylon, inserted through a tangential hole in the socket wall, into preformed tangential grooves in the male and female end of the tube. The Ameron Key-lock™ system is a good example. Rubber seal joints enable long pipe runs to be laid with low handling and labour costs. The joint itself can accommodate a few degrees of flexure, making it possible to lay the system over ground with minimal preparation. The pressure rating of the joint can be improved by the use of more than one key. For higher-pressure applications, socket and spigot joints with moulded threads are successfully used, sometimes in conjunction with a thread sealant or adhesive. The thread design is often similar to the API tapered threads used with steel tubing. Aerospace applications The very important topic in my paper is this aerospace applications topic. Applications of these composites in aerospace engineering being aerospace composites parts, we must be giving a layout of aircraft. Without possibilities of amalgamating the above explanations and lightweight panel can be produced by using fibre-reinforced composites. All the components parts can be produced by using fibre-reinforced composites panels and door parts. Aircraft application The advanced composites in the construction of aircraft and helicopters, weight savings of 20 - 30% are achieved as compared to conventional materials. Fairings, landing gears, engine cowls, rudder, fin boxes, doors, floor boards and many other interior gadgets are made of advanced composites in combination with metallic and non-metallic honey comb cores and metals. The recently launched prototype of Advanced Light Helicopter (ALH) is said to have as much as 60% of the surface area made up of composite components including advanced fibre components and metal sandwich structures. Space crafts: Two factors, high specific modulus and strength, and dimensional stability during large changes in temperature in space make composites the material of choice in space applications. Examples include the graphite/epoxy-honeycomb payload bay doors in the space shuttle. Weight savings over conventional metal alloys translate to higher payloads which cost as much as $1000/lb ($2280/kg) also, for the space shuttles remote manipulator arm, which deploys and retrieves payloads, graphite/epoxy was chosen primary for weight savings and for small mechanical and thermal deflections. Antenna ribs and struts in satellite systems use graphite/epoxy for their high specific stiffness and its ability to meet the dimensional stability requirements due to large temperature excursions in space. Remember "aerodynamic heating" during re-entry should also be taken into concern. Rocket and missiles Rocket motor cases and liners are made using composites of carbon, aramid and glass. Formulated epoxies, phenolics and polyimide materials are being used. Carbon-carbon composites are used for re-entry nose tips and heat shields. These applications, which require a lower ablation rate, higher bulk density and superior mechanical strength, are possible with carbon-carbon composites compared to monolithic graphite. Carbon-carbon composite items are successfully made from 3-D fabrics followed by densification process. Marine application Development of composite propulsion shafts for naval vessels is being investigated to replace the massive steel shafts that comprise up to 2% of the ship's total weight. Composite shafts of glass and carbon reinforcing fibres in an epoxy matrix are projected to weigh 75% less than the traditional steel shafts and offer the advantages of corrosion resistance, low bearing loads, reduced magnetic signature, higher fatigue resistance, greater flexibility, excellent vibration damping and improved life-cycle cost. Tensile behaviour of knitted fabrics composite Composites are fabricated by impregnating knitted fabric of reinforcement fibre yarns with the matrix polymer. For a given knitted fabric structure, the mechanical behaviour of composite material depends on the properties of the constituent fibre and matrix materials. Typical tensile stress-strain curves of three different kinds of knitted fabric composites. These curves are obtained from tensile testing in the wale direction of the composite. The tensile stress-strain curve of composite made from knitted glass fibre fabric and epoxy matrix is grossly linear with a small failure strain 1.3%. Knitted Glass fibre-reinforced composites for epoxy resin, polypropylene and polyurethane fibres. In the case of knitted glass fibre fabric reinforced polypropylene composite material, the stress-strain curve changes from an initial linearly elastic relationship to a significantly nonlinear relationship with an intermediate ultimate failure strain of 8.5%. The matrix polymer used in these composite materials mainly causes this difference. At the other end of the spectrum, a highly flexible stress-strain behaviour could be achieved by reinforcing elastomeric material with a knitted fabric. A typical stress-strain curve of knitted polyester fibre fabric reinforced polyurethane elastomeric is shown in the Figure. The stress-strain behaviour is characterised by a small initial linear elastic relationship, followed by nonlinear behaviour with large ultimate failure strain of 60%. In other words, by selecting the type of matrix and reinforcement materials, the mechanical characteristics of a knitted fabric composite can be tailored from rigid to flexible. This chapter mainly concerns the mechanical behaviour of the knitted glass fibre fabric reinforced epoxy composites, in which the stresses and strains are connected by fixed linear relationships. The stress-strain curve is linear up to the knee point, which occurred at approximately 0.45% strain. Above the knee point, the material deformation and microfracture processes in the specimen cause the nonlinearity. A schematic representation of a typical fracture process in a knitted fabric composite is shown in the figure. Above the knee point, debonding of yarns oriented normal to the testing direction occurs. The cracks nucleated from the deboned sites propagate into resin-rich regions and coalesce into large transverse cracks. Unfractured yarns bridge the fracture plane. The ultimate fracture of the tensile specimen occurs upon the fracture of bridging yarns. In other words, the tensile strength of composite material is determined mainly by the fracture strength of yarns bridging the fracture plane. Conclusion Fibre-reinforced composites often aim to improve the strength to weight and stiffness to weight ratios. These properties will reduce the weight of the components produced by the fibres and therefore fibres used for composite materials will have high strength, high flexibility and it is most widely used for textiles and other major fields. Fibre-reinforced composites are mostly widely used in the concretes, marine, aircraft, conveyor belts and other manufacturing applications. The future scope for the reinforced fibre is more and its application is spreading in all the fields of science and engineering. Still researches are going under this to improve their properties and applications of different fibres in various fields. Original Articles were published in http://www.indiantextilejournal.com/articles/FAdetails.asp?id=5096

Types of Dyeing

Colour is applied to fabric by different methods of dyeing for different types of fiber and at different stages of the textile production process. Dyeing can be done during any stage in the textile manufacturing process. Textiles may be dyed as fibre, as yarn, as fabric, as garments, depending upon the type of the fabric or garment being produced.

These methods include direct dyeing; Stock dyeing; top dyeing; Yarn dyeing; Piece dyeing; Solution pigmenting or dope dyeing; Garment dyeing etc. Of these Direct dyeing and Yarn Dyeing methods are the most popular ones.

 

Direct Dyeing
When a dye is applied directly to the fabric without the aid of an affixing agent, it is called direct dyeing. In this method the dyestuff is either fermented (for natural dye) or chemically reduced (for synthetic vat and sulfur dyes) before being applied. The direct dyes, which are largely used for dyeing cotton, are water soluble and can be applied directly to the fiber from an aqueous solution. Most other classes of synthetic dye, other than vat and sulfur dyes, are also applied in this way.

 

Stock Dyeing
Stock dyeing refers to the dyeing of the fibers, or stock, before it is spun in to yarn. It is done by putting loose, unspun fibres in to large vats containing the dye bath, which is then heated to the appropriate temperature required for the dye application and dyeing process.

Stock dyeing is usually suitable for woolen materials when heather like color effects are desired. Wool fibre dyed black, for example, might be blended and spun with un-dyed (white) wool fibre to produce soft heather like shade of grey yarn.

Tweed fabrics with heather like color effects such as Harris Tweed are examples of stock dyed material. Other examples include heather like colours in covert and woolen cheviot.

Top Dyeing
Top dyeing is also the dyeing of the fibre before it is spun in to yarn and serves the same purpose as stock dyeing – that is, to produce soft, heather like color effects. The term top refers to the fibres of wool from which the short fibres have been removed. Top is thus selecting long fibres that are used to spin worsted yarn. The top in the form of sliver is dyed and then blended with other colors of dyed top to produce desired heather shades.

 

Yarn Dyeing
Yarn dyeing is the dyeing of the yarns before they have been woven or knitted into fabrics. Yarn dyeing is used to create interesting checks, stripes and plaids with different-colored yarns in the weaving process. In yarn dyeing, dyestuff penetrates the fibers in the core of the yarn. There are many forms of yarn dyeing- Skein (Hank) Dyeing, Package Dyeing, Warp-beam Dyeing, and Space Dyeing.

 

A. Skein (Hank) Dyeing
Skein dyeing consists of immersing large, loosely wound hanks (skeins) of yarn into dye vats that are especially designed for this purpose. Soft, lofty yarns, such as hand knitted yarns are usually skein dyed. Skein dyeing is the most costly yarn-dye method.

 

B.Package Dyeing
In package dyeing the yarn is wound on a small perforated spool or tube called a package. Many spools fit into the dyeing machine in which the flow of the dye bath alternates from the center to the outside, and then from the outside to the center of the package. Package dyed yarns do not retain the softness and loftiness that skein-dyed yarns do. They are however satisfactory and very widely used for most types of yarns that are found in knitted and woven fabrics.

C. Warp Beam Dyeing
Beam dyeing is the much larger version of package dyeing. An entire warp beam is wound on to a perforated cylinder, which is then placed in the beam dyeing machine, where the flow of the dye bath alternate as in the package dyeing. Beam dyeing is more economical than skein or package dyeing, but it is only used in the manufacture of woven fabrics where an entire warp beam is dyed. Knitted fabrics, which are mostly produced from the cones of the yarn, are not adaptable to beam dyeing.

 Piece Dyeing
The dyeing of cloth after it is being woven or knitted is known as piece dyeing. It is the most common method of dyeing used. The various methods used for this type of dyeing include jet dyeing. Jig dyeing, pad dyeing and beam dyeing.
 

Garment Dyeing
Garment dyeing is the dyeing of the completed garments. The types of apparel that can be dyed are mostly non-tailored and simpler forms, such as sweaters, sweatshirts, T-shirts, hosiery, and pantyhose. The effect on sizing, thread, zippers, trims and snaps must be considered. Tailored items, such as suits or dresses, cannot be dyed as garments because the difference in shrinkage of the various components and linings disort and misshape the article.

Garment dyeing is done by placing a suitable number of garments (usually about 24 sweaters or the equivalent, depending on the weight) into large nylon net bag. The garments are loosely packed. From 10 to 50 of the bags are placed in large tubs containing the dye bath and kept agitated by a motor – driven paddle in the dye tub. The machine is appropriately called a paddle dryer.

Read more http://textilelearner.blogspot.in/2011/12/methods-of-dyeing-different-dyeing.html

TESTING AND PURITY ANALYSIS FOR CHEMICALS

 

Prof. Aravin Prince Periyasamy, M.Tech

DKTE Textile & Engineering Institute, Ichalkaranji, Kolhapur, India.

E-Mail: aravinprince@gmail.com  Blog: www.aravinprince.blogspot.in

 

1.      DETERMINATION OF AVAILABLE CHLORINE IN SODIUM HYPOCHLORITE SOLUTION

Method A:

Pipette 25 ml of the sample and transfer to a 500 ml volumetric flask containing about 300 ml ice cold water. Dilute to the mark with ice cold water and mix well.

Take 25 ml aliquot in a 250 ml conical flask. Add about 50 ml ice cold water and about 2 gm NaHCO₃. Titrate with N/10 arseneous acid solution. First test with KI-starch indicator papers when the blue test becomes faint. Add about 1 gm solid KI and starch solution. Titrate further till the blue colour disappears.

ml N / 10 arseneous acid ´ 0.003546 ´ 500 ´ 100

________________________________________ = % available Chlorine (w / v)

                               25 ´ 25

Method B:

Take 10 ml sample in 100 ml standard volumetric flask and make up to the mark with distilled water. Call this solution ‘A’. Take 10 ml solution from ‘A’ in 100 ml conical flask containing about 25 ml distilled water. Add 2-3 gms. KI crystals and 5 ml glacial acetic acid. Quickly stopper the flask, shake well and titrate against N / 10 Na₂S₂O₃ solution using starch solution as indicator till discharge of Blue colour.

Rd ´ N ´ 3.55 ´ 100

________________________________________ = Available Chlorine (gms./ L)

                               0.1 ´ 10 ´ 10

Rd = ml. of N / 10 Na₂S₂O₃

N = Normality of N/ 10 Na₂S₂O₃

2.      DETERMINATION OF Na₂O: SiO₂ IN SODIUM SILICATE

About 5 gms. of the paste sample is weighed out accurately and transfer to 100 ml volumetric flask with water and make upto the mark with water. Stir well. From this solution, pipette out 10 ml in 250 ml conical flask containing 50 ml water and titrate against 1 N H₂SO₄ using methyl orange indicator. Call this burette reading “M”. Further add sodium fluoride (about 5 gm) and the second titration is made to methyl red end point when liberated sodium hydroxide reacts with the acid. Call this burette reading “P”.

Calculation:

                 “M” ´ Normality ´ 31 

________________________________________ = % Na₂O

                    1 ´ Weight of sample

                 “P-M” ´ Normality ´ 60

________________________________________ = % SiO₂

                1 ´ 4 ´ Weight of sample

3.      DETERMINATION OF HARDNESS IN WATER

Hardness in water is caused mainly by the presence in solution of various compounds of calcium and magnesium. It is customary and necessary to distinguish between two kinds of hardness:

(a)    Temporary Hardness (sometimes referred to as Carbonate Hardness)

Temporary Hardness results from the presence of bicarbonates of calcium and magnesium, and is so called from the fact that it is for the most part destroyed by boiling.

(b)   Permanent Hardness (Non-carbonate Hardness)

Permanent Hardness is caused by the presence of the sulphates, chlorides and nitrates of calcium and magnesium, and is not destroyed by boiling at atmospheric pressure.

In order to express the hardness of water quantitatively it is usual to calculate the calcium and magnesium compounds present in terms of their equivalent of calcium carbonate (CaCO₃). The hardness is then stated in terms of ‘parts CaCO₃ per 100,000’.

E.D.T.A. Method:

Special reagents required:

1. Reagent A – N / 50 E.D.T.A. i.e. Disodium dihydrogen ethylene diammine tetraacetate. Dissolve 3.72 gms of crystalline dihydrate in distilled water and dilute to 1 litre.
2. Reagent B – Ammonia buffer solution

Add 16.875 gms of Ammonium chloride to 142.5 cc of Ammonium hydroxide solution (sp. gr. 0.880) and dilute to 225 cc with distilled water.

Separately dissolve 0.1540 gms of Magnesium sulphate (MgSO₄, 7 H₂O) in 12.5 cc distilled water and add 0.2325 gms of solid E.D.T.A. Add this to Ammonium hydroxide / Ammonium chloride mixture and dilute with distilled water to 250 cc.

3. Reagent C – Total hardness indicator

Add 0.5 gm Solochrome Black GDFA to 100 cc of alcohol (industrial methylated spirit). Warm to dissolve the dyestuff and add 4.5 gms of Hydroxylamine hydrochloride. Allow to stand overnight and filter.

Note: This solution should not be used after one month.

Procedure:

Total Hardness

Transfer 100 cc sample of water to porcelain casserole. Add 2 cc Ammonium Buffer solution (Reagent B) and six drops of indicator (Reagent C). Titrate immediately with E.D.T.A. solution until the solution has lost all traces of red colour. At this point, final colour is usually pure blue but with some water a neutral grey end point is obtained.

Note: When hardness is greater than 250 ppm as CaCO₃, use 50 cc or smaller sample.

            Tire reading ´ 1000

        ____________________ = Total Hardness (ppm as CaCO₃)      

             Sample taken in ml.

[Note: 1^o German hardness = 18 ppm]

4.      DETERMINATION OF PURITY OF SODIUM CARBONATE (SODA ASH)

Accurately weigh 5.50 gms. of the sample. Transfer to a 500 ml conical flask with 100 ml distilled water and dissolve completely by shaking. Observe for the presence of turbidity. Add 5 to 6 drops of indicator methyl orange solution and titrate with a standard N / 1 Sulphuric acid solution till the yellow colour changes to orange red.

Calculation:

ml of N / 1 Sulphuric acid ´ 0.053 ´ 100

________________________________________ = % Na₂CO₃ alkalinity

                               5.3

5.      ANALYSIS OF CAUSTIC SODA FLAKES:

Strength as NaOH and Carbonate as Na₂CO₃

Weigh out accurately from a stoppered weighing bottle 18-20 gms. of the material into a 500 ml beaker. Add 250 ml cold carbon dioxide free water. Stir until dissolved, cool, transfer into a 500 ml measuring flask, dilute to the mark at room temperature with carbon dioxide free water and mix well. Call this solution ‘A’.

Transfer 50 ml solution ‘A’ to a 250 ml conical flask, dilute to 150 ml with water and titrate with N / 1 Hydrochloric acid using phenolphthalein as indicator, till the pink colour disappears. Take this reading as P ml. Then add 0.5 ml bromophenol blue solution and further titrate with N/1 Hydrochloric acid until the blue colour changes to greenish blue. Take this reading as M ml.

Calculation:

                           M – 2(M – P) ´ 40

________________________________________ = % Strength as NaOH

                               Weight taken

       2(M – P) ´ 53

________________________________________ = % Carbonate as Na₂CO₃

                               Weight taken

6.      ANALYSIS OF SODIUM HYDROSULPHITE (SODIUM DITHIONITE) (HYDROS)

Remove the top layer of the sample and weigh accurately in a tared weighing bottle 8.0 – 8.5 gms. of the material remaining in the sample bottle without mixing. Place 40 ml 40% formaldehyde solution and 910 ml boiled-out and cooled water in a 1 litre volumetric flask with a short neck (about 1 inch above the graduation mark), mix well, give the liquid in the flask a swirling motion, and pour in the weighed sample through a short stemmed funnel. Wash the funnel and weighing bottle rapidly with boiled-out and cooled water, dilute to the mark, and mix well. The swirling motion given to the liquid prevents the dithionite from forming a cake at the bottom of the flask. Allow the solution to stand for at least 15 minutes so that the reaction between the dithionite and formaldehyde may be complete. Call this solution A.

Place about 100 ml boiled-out and cooled water in a 500 ml conical flask, and add 25 ml Solution A by means of a pipette. Add 5 ml glacial acetic acid and 50 ml N/10 iodine, allow to stand for 2 minutes, and titrate the excess of iodine with N/10 sodium thiosulphate, slowly towards the end-point, using freshly prepared starch solution as indicator added towards the end of the titration.

Carry out a control test using 25 ml boiled-out and cooled water instead of 25 ml Solution A.

Calculation:

Let, A = ml N/10 Na₂S₂O₃ required in control test

and B =  ml N/10 Na₂S₂O₃ required in test

                              (A-B) ´ 17.41

                     ____________________ = Strength calculated as % Sodium Hydrosulphite

                               Weight taken                                                        (M.W. 174.1)

7.      ANALYSIS OF GLAUBER’S SALT (SODIUM SULPHATE)

Take 1 gm of the sample and dilute it with 100 ml distilled water in volumetric flask. Take 50 ml Acetone in conical flask and add 10 ml of the above solution along with 2 ml Di-thiozone indicator and add 1 to 2 drops of Nitric acid till colour changes. Add 2 ml Buffer solution and titrate with 0.01 M Pb(NO₃)₂ till colour changes from blue-green to brick red.

Calculation:

            Burette reading´ 0.142 ´ 100

            ___________________________ = % Na₂SO₄

                     Weight taken ´ 10                                                      

Note:

Di-Thiazone indicator –

0.05 gms indicator + 100 ml Acetone

Buffer solution –

Take 200 ml. water. Add 46 ml of Dichloro acetic acid, followed by 40 ml 10 N NH₃ & adjust pH 7.0. Add 22 ml of Dichloro acetic acid and adjust pH 1.5 – 2.0. Make total volume of 500 ml.

0.01  M Pb(NO₃)₂ –

Dissolve 16.560 gms. of Pb(NO₃)₂ in 500 ml distilled water. Take 50 ml of this solution and dilute to make 500 ml with distilled water.

8.      DETERMINATION OF PURITY OF SODIUM CHLORIDE (COMMON SALT)

Dissolve 5.845 gms of the sample in water and make upto 1000 ml volume in a volumetric flask. Mix well.

Pipette 50 ml aliquot of the above solution into a 500 ml Erlenneyer flask, add 4 drops of 10% w/v K₂CrO₄ indicator solution and about 0.5 gm of c.p. CaCO₃. Titrate against a standard N/10 silver nitrate solution until the orange pink tint due to Ag₂CrO₄ precipitate is produced. This indicates the end point.

Calculation:

ml of N / 10 AgNO₃ required ´ 0.005845 ´ 1000 ´ 100

_______________________________________ = ml of N / 10 AgNO₃ required ´ 2 = % NaCl.

                               50 ´ 5.845 

9.      DETERMINATION OF PURITY HYDROGEN PEROXIDE

Weigh 2 gms of sample in glass stopper bottle & dilute it up to 250 ml with volumetric flask. Pipette out 10 ml of this solution, add 50 ml of water & 20 ml of 10% sulphuric acid & titrate against 0.1 KMNO₄ to the appearance of faint pink colour.

.

Calculation:

            Burette reading´ 42.52 ´ Normality of KMNO₄

            ___________________________                  = % Purity

                       Weight taken

10 Volume = 3% of H₂O₂