use of us energy in enzymatic pre treatment of cotton fabric

SYNTHETIC FIBRE DEVELOPMENT & APPLICATION CENTRE

College of Textile Engineering

AN AFFILIATED INSTITUTION OF HAMDARD UNIVERSITY

Semester VIII

Project Thesis

Final Report

B.E. (Textile)

12th Batch

Project Title:

“USE OF ULTRASONIC ENERGY IN ENZYMATIC PRE TREATMENT OF100% COTTON FABRIC”

Project supervisor:

Prof. Dr. Ahmed Niaz

Project Members:

Mohsin Fareed (12-TE-37)

Kaleemullah (12-TE-29)

Kashif Rafique (12-TE-31)

Syeda Afia Ahmed (12-TE-93)

Ishaq Bin Ismaeel (12-TE-34)

ACKNOWLEDGEMENT

“All Praise to the Almighty ALLAH who is The MostBeneficent Most Merciful.”

This project can’t become a reality without the support, assistance andcooperation of Prof. Dr. AHMED NIAZ. We therefore grateful to him for

his expert help.We also thankful to our respected teachers of SFDAC who guide us in

our studying and mold us, such that we can survive in theTEXTILE INDUSTRY

S.No. CONTENTS PageNo.

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Abstract

Introduction

Introduction to Ultrasound

Constituents of Raw Cotton

Introduction to Enzymes

Materials & Method

Desizing

Bio-Scouring

Bleaching

Combined Desizing & Bio-Scouring

Solomatic Bleaching

Combined Desizing, Bio-Scouring & Bleaching

Results & Discussions

Summary

Conclusions & Recommendations

References

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ABSTRACT

USE OF ULTRASONIC ENERGY IN ENZYMATIC PRE-TREATMENT OF 100% COTTON FABRIC 1

ABSTRACT

The field of ultrasonics is still making strides towards perfection, but already manyapplications of ultrasonic energy have been found in science and technology.Ultrasonics is the science of sound waves above the limits of human audibility. Theaim of this study was to investigate the effects of ultrasound on textile pre-treatmentprocesses especially on enzymatic processes. Use of enzymes in the textile industryhas become more popular in recent years. Although enzymatic processing offers manyadvantages, there are a few drawbacks when compared to traditional methods,namely, expensive processing costs and relatively slow reaction rates. Introducingultrasonic energy during enzymatic treatment of cotton fabric significantly improvesenzyme efficiency without affecting the strength of the fabric.

INTRODUCTION


INTRODUCTION:

Use of enzymatic processing in the food, textile and bio-fuel applications is becomingincreasingly popular, primarily because of rapid introduction of a new variety ofhighly efficient enzymes. In general, an enzymatic bio-processing generates less toxicand readily bio degradable waste water effluent. The ever increasing legislativepressures by governments worldwide to reduce the quantity/toxicity of industrialwaste water will ensure even greater acceptance of enzymatic bio-processing infuture.

Enzymatic processing of cotton textiles, like any wet processing system, involvestransfer of mass (enzyme macromolecules) from the processing liquid medium(enzyme solutions) across the surface of the textile substrate.

Enzymatic reaction involves transfer of enzyme macromolecules and enzymaticreaction products to and from the fiber surface. Since both stages are controlled bydiffusion, the overall reaction rate of enzymatic hydrolysis is governed by thediffusion rate of enzyme macromolecules. In general, large three dimensional enzymemacromolecules have low diffusion rates and tend to react with outlaying cellulosefibers in cotton yarn, which could result in excessive fiber damage.

Sonication of enzyme processing solution under specific conditions could provide afar more efficient transport mechanism, for bulky enzyme macromolecules throughoutthe immediate border layer of liquid at the substrate surface. This is because ofsonication that provides enzymatic solution a mechanical movement and thussupporting mass (enzymes macromolecules) transfer into the chore of fiber.

MATERIAL & METHODS


INTRODUCTION TO ULTRSOUND:

Ultrasound is cyclic sound pressure with a frequency greater than the upper limitof human hearing (the range of human hearing is 16Hz to 16KHz). Although this limitvaries from person to person, while the ultrasonic waves lie s between 20KHz to500MHz. Ultrasonic vibration travel in the form of a wave, similar to the way lighttravel. However, unlike light waves which can travel in a vacuum. Ultrasoundrequires an elastic medium such as a liquid or a solid. However, the frequency rangenormally employed in ultrasonic non destructive testing and thickness gagging is 100KHz to 50 MHz. although ultrasound behaves in a similar manner to audible sound. Ithas a much shorter wavelength. This means it can be reflected off vary small surfacessuch as defects inside materials. It is the property that makes ultrasound useful for nondestructive testing of material.

The acoustic spectrum in below figure classifies sound into ranges of frequencies.

MECHANISM OF ULTRASONIC ENERGY:

When a liquid, in which gas is dissolved, is irradiated by a strong ultrasonic wave,many tiny bubbles appears. The bubbles repeat their expansion and contractionaccording to the pressure oscillation of an ultrasonic wave. Some bubbles collapseviolently at the contraction phase of an ultrasonic wave. The temperature and pressureinside the bubbles increase to 5000 K and 300atm, respectively or more in the strongcollapse. Due to the high temperature and pressure inside the bubbles in the strongcollapse, water vapor inside the bubbles is dissociated and chemical products such asOH-(hydroxyl group), H+ (atomic hydrogen), H2O2 (hydrogen peroxide), HO2(superoxide) and H2(molecular hydrogen) molecules are created inside the bubbles .Because of this energy, power ultrasound has great use in different areas.

ULTRASONIC ENERGY IN TEXTILE WET PROCESSING:

In recent years, power ultrasound has been used in dyeing, washing and theenzymatic scouring process, since it increases the mass transfer effect. Even though itis being used in these areas, it is not yet clearly understood how ultrasound improvesmass transfer. It is characterized as a kind of black box, because the effect of thefrequency and intensity of ultrasound, the effect of environmental conditions and thereason for the interaction between the textile surface and ultrasonic waves are notknown.

MATERIAL & METHODS


Mass transfer is usually in limited levels in conventional pretreatment and finishingprocesses. For this reason, these processes need respectively longer processing times,more water and chemicals. Thus, more energy is consumed. The efficiency of the wetfinishing process is increased by raising the mass transfer towards to the inner parts ofthe textile material.

Textile material can be described as a porous, not homogeneous medium. Woventextile material has two different pores being interspaced between yarns and fibres.The basic steps of mass transfer in textile materials are:

Mass transfer from the pores between fibres to the pores between yarns. Mass transfer from the pores between yarns to the interface of textile material/liquid Mass transfer from the textile material/liquid interface to the liquid.

Since the pores between the fibres are smaller, their resistance to the liquid flow isgreater and they cause a large part of the liquid to flow through these pores betweenthe yarns without penetrating into the pores between fibres, while the mass transferbetween the yarns is realised by convection, diffusion is the way of mass transferfrom the fibres to the solution. The step determining the speed in mass transfer isdiffusion, since it happens more slowly than convection.

Warmoeskerken mentions two terms: stagnant region and convective region in orderto describe the flow towards the yarns and mass transfer. A stagnant region in a yarnis where there is no flow. A convective region is the outer side of a yarn into whichthe flow can penetrate to a certain degree (Figure 1). Mass transfer is realized bymolecular diffusion in the stagnant region, and by convective diffusion in theconvective region. Since convective diffusion is faster than molecular diffusion, thestagnant region determines the speed of removing the impurities. This means tocontract the stagnant region by mechanical energy in so far as it is possible.

MATERIAL & METHODS


USE OF ULTRSONIC ENERGY IN PRE-TREATM ENT:

Even though enzymatic processing of cotton goods provides some savings, there is adrawback of high costs and relatively low reaction speed of enzymes. Both stepsincluding the transfer of enzyme macromolecules and products obtained as a result ofhydrolysis are based upon the principle of diffusion, and the speed of diffusiondetermines the reaction speed of hydrolysis. In general, large enzyme macromolecules(12.0 - 150.0 kDa) have lower diffusion speed. For example, in the processing ofcellulose it has the tendency to react with the outer cellulosic fibres of cotton yarn. Asa result, extreme fibre damage can be observed. Diffusion of the enzymes can beimproved by giving mechanical movement. However, in this way it is not so easy togive mechanical movement on the interface of liquid/fibre where enzymatic reactionis realised. In this case, ultrasound technology seems as an alternative.

Generally, an application of ultrasound energy into the liquid medium has twoprimary effects i.e. cavitation and heating:

Cavitation: Sonication of liquid by low frequencies dissipates most of the ultrasoundenergy through cavitation phenomena.

Heating: Sonication by high frequencies dissipates a significant amount of energythrough heating.

In case of enzymatic bio-processing, the more important is cavitation- formation,growth, and implosive collapse of bubbles in a liquid. Sonication frequency givesgood results in the range from 20-100KHz but it is appear that the optimum results areobtained at 20-25KHz. There are two important properties of cavitation.

The effect of cavitation in heterogeneous systems is hundreds of times more thanhomogeneous ones. The maximum effect of cavitation in water is seen at 49 °C. Thistemperature is also optimum for most of enzymatic processes. The most importantpoint is that shock waves in ultrasound do not inactivate the enzyme. The diffusion ofenzyme onto the fibre surface increases as long as it does not affect the activation.

The following mechanisms take place in the ultrasonic process:

Increase in the swelling of fibres in water. Decrease in the glass transition temperature of the fibre. Increase in the diffusion coefficient of the dye molecule. Increase in the fibre/dye partition coefficient. Improvement in the movement of dye molecules to the fibre surface. Disintegration of aggregates having high molecular weight in the solution.

The following specific features of cavitation phenomena are very important forpractical bio-processing application:

Effect of cavitation is several hundred times greater in heterogeneous (e.g. all textilewet processing) than in homogeneous systems.

In water, maximum effects of cavitation occur at 50oC, which is the nearly optimumtemperature for many enzymatic bio-processing applications.

MATERIAL & METHODS


However, when ultrasound specifically is used to inactive enzymes and terminateenzymatic activity its actual efficiency is affected. For example, the combined effectof heat, ultrasonic waves and pressure may be used for inactivation of certainthermostable enzymes. The comprehensive overview of the combined effect of heat,pressure and ultrasound on microorganisms and enzymes enfold that the resistance ofmost microorganisms and enzymes to ultrasound is so high that the required intensityof ultrasound treatment would be impractical.

MATERIAL & METHODS


CONTITUENTS OF RAW COTTON:

Cotton fibres consist mainly of high molecular weight, long chain cellulosicmolecules that are polymerised from β-d-glucose monomers. Being organicallyproduced, the cellulose component is associated with small quantities of proteins, oilyproducts, pectins, colouring matter and some mineral salts. These non-cellulosiccomponents are located in the outermost cuticle layer (that is 0.5-0.1 µm thick) andthe primary wall of the cotton fibres. The non-cellulosic constituents are considered asimpurities of cotton in the manufacturing processes and are therefore removed bytreatment with the hot caustic soda solution prior to the dyeing, printing and finishingof the material. Depending upon the variety of cotton, quantity of these impuritiesranges between 6 to 9%. Proportion of the constituents of this non-cellulosic matter inthe whole fibre and the cuticle are given in the following table.

Figure: An idealised morphology of cotton fibre developed byShirley Institute, Manchester

Cellulose 88-96%Oil and Wax 0.4-1.0%Pectins 0.7-1.2 %Proteins 1.1-1.9 %Mineral Matter (Ash) 0.7-1.6 %Other Organic Matter 0.5-1.0 %

MATERIAL & METHODS


INTRODUCTION TO ENZYMES:

The use of enzymes in the textile chemical processing is rapidly gaining globallyrecognition because of their non-toxic and eco-friendly characteristics with theincreasingly important requirements for textile manufacturers to reduce pollution intextile production. Enzymes sources, activity, specificity, reaction, mechanism andthermodynamics, function of textile processing with enzymes, major enzymaticapplications in textile wet processing and promising areas of enzyme applications intextile processing are discussed. The aim is to provide the textile technologist with anunderstanding of enzymes and their use with textile materials.

ENZYMES ARE PROTEIN:

Enzymes are generally globular proteins and like other proteins consist of long linearchains of amino acids that fold to produce a three-dimensional product. Each uniqueamino acid sequence produces a specific structure, which has unique properties.Individual protein chains may sometimes group together to form a protein complex.

BIOCATALYST:

Enzymes are biocatalysts, and by their mere presence, and without being consumed inthe process, enzymes can speed up chemical processes that would otherwise run veryslowly. After the reaction is complete, the enzyme is released again, ready to startanother reaction. Most of the biocatalyst have limited stability and over a period oftime they lose their activity and are not stable again. Usually most enzymes are usedonly once and discarded after their catalytic action.

ACTIVITY:

The activities of enzymes are determined by their three-dimensional structure. Mostenzymes can be denatured, which disrupt the three-dimensional structure of theprotein. Denaturation may be reversible or irreversible depending on the enzyme.There are two proposed models of enzyme substrate complex formation.

LOCK-AND-KEY MODEL OR TEMPLATE:

In 1894 Emil Fischer provided the lock-and-key model assuming that the active site isa perfect fit for a specific substrate and that once the substrate binds to the enzyme nofurther modification is necessary. It is a simplistic model.

INDUCED FIT MODEL OR KOSHLAND MODEL:

In 1958 Daniel Koshland suggested a modification to the lock and key model. Insteadof flexible structures, the active site is continually reshaped by interactions with thesubstrate as the substrate interacts with the enzyme. As a result, the substrate does notsimply bind to a rigid active site; the amino acid side chains which make up the activesite are molded into the precise positions that enable the enzyme to perform itscatalytic function. In some cases, such as glycosidases, the substrate molecule alsochanges shape slightly as it enters the active site.

MATERIAL & METHODS


The active site continues to change until the substrate is completely bound, at whichpoint the final shape and charge is determined. The product is usually unstable in theactive site due to steric hindrances that force it to be released and return the enzyme toits initial unbound state.

ENZYMATIC REACTION:-

Victor Henri elaborated enzyme reactions in two stages. In the first, the substratebinds reversibly to the enzyme, forming the enzyme-substrate complex. This issometimes called the Michaelis complex. The enzyme then catalyzes the chemicalstep in the reaction and releases the product.

MECHANISIM:-

Enzymes can act in several ways, all of which lower ΔG‡:

Lowering the activation energy by creating an environment in which the transitionstate is stabilized. Lowering the energy of the transition state, but without distorting the substrate, bycreating an environment with the opposite charge distribution to that of the transitionstate. Providing an alternative pathway. For example, temporarily reacting with thesubstrate to form an intermediate ES complex, this is not possible without enzyme. Reducing the reaction by bringing substrates together in the correct orientation toreact. Reactions speed up with increase in temperatures. However, the enzyme’s shapedeteriorates on overheating and only when the temperature comes back to normaldoes the enzyme regain its shape. Some enzymes like thermolabile enzymes workbest at low temperatures.

MATERIAL & METHODS


Enzymes like all catalysts do not alter the position of the chemical equilibrium of thereaction. They do not alter the equilibrium itself, but only the speed at which it isreached. Usually, in the presence of an enzyme, the reaction runs in the samedirection as it would without the enzyme, just more quickly. However, in the absenceof the enzyme, other possible uncatalyzed, spontaneous reactions might lead todifferent products, because in those conditions this different product is formed faster.

USE OF ENZYMES IN PRE-TREATMENT:

Most of the textile enzymes are those that catalyze the digestion or hydrolysis ofcertain large organic molecules like starch, cellulose, and protein. The enzymesactually attack these complex molecules, accelerating their digestion and yieldingsimpler substances.

Since this process of digestion is referred to as hydrolysis, the enzymes that catalyzethe process are considered to be hydrolyzing enzymes or hydrolases.

AMYLASE:-

All amylases are glycoside hydrolases and act on α-1, 4-glycosidic bonds thathydrolyse starch down into sugar. Amylase is present in human saliva; the pancreasalso makes amylase. Plants and some bacteria also produce amylase.

Specific amylase proteins are designated by different Greek letters. The α-amylases(EC 3.2.1.2) are calcium metalloenzymes, completely unable to function in the

MATERIAL & METHODS


absence of calcium. By acting at random locations along the starch chain, α-amylasebreaks down long-chain carbohydrates, ultimately yielding maltotriose and maltosefrom amylose, or maltose, glucose and limit dextrin from amylopectin. α-amylasetends to be faster-acting than β-amylase as it can act anywhere on the substrate. β-amylase (EC 3.2.1.2) is also synthesized by bactetria, fungi, and plants.

Working from the non-reducing end, β-amylase catalyzes the hydrolysis of the secondα-1, 4 glycosidic bond, cleaving off two glucose units (maltose) at a time. In additionto cleaving the last α-1, 4 glycosidic linkages at the nonreducing end of amylose andamylopectin, yielding glucose, γ-amylase (EC 3.2.1.3) cleaves α-1, 6 glycosidiclinkages. Unlike the other forms of amylase, γ-amylase is most efficient in acidicenvironments and has an optimum pH of 3. Starch is used as a sizing agent in textilecomprising of linear chained amylose and branched chain amylopectin. The desizingprocess was carried out by treating the fabric with chemicals such as acids, alkali oroxidizing agents.

The amylose is bioconverted to 100% by the alpha- amylase into glucose whereas theamylopectin is converted to 50% into glucose and maltose. Bio desizing is preferreddue to their high efficiency and specific action. Amylases bring about completeremoval of the size without any harmful effects on the fabric besides eco friendlybehavior.

PECTINASE:-

Pectinase (EC 3.2.1.15) is a general term for enzymes such as pectolyase, pectozymeand polygalacturonase. Pectinases hydrolyse pectin, a polysaccharide substrate that isfound in the cell walls of plants into galacturonic acid and small sugars.Commercially available pectinases contain only very little cellulases and fiber damageshould be limited as cellulose itself is not targeted. Pectinases are reported fromvarious microbial sources. Fungal pectinases have been extracted from Aspergillusniger, Penicillium frequentans, Sclerotium rolfsii, and Rhizoctonia solani. Howeverthese enzymes are optimally active in acidic conditions. Alkaline active pectinaseshave been obtained from Penicilium italicum and Aspergillus sp. Pectinases have anoptimum temperature and pH at which they are most active. For example, acommercial pectinase might typically be activated at 45 to 55 °C and work well at pHof 4.5 to 5.5. If pectinase is boiled it is denatured making it harder to connect with thepectin at the active site.

Today, highly alkaline chemicals caustic soda is used for scouring. These chemicalsnot only remove the non-cellulosic impurities from the cotton, but also attack thecellulose leading to heavy strength loss and weight loss in the fabric. Furthermore,using these hazardous chemicals result in high COD, BOD and TDS in the wastewater. Recently a new enzymatic scouring process known as 'Bio-Scouring' is used intextile wet-processing with which all non-cellulosic components from native cottonare removed. After this Bio-Scouring process, the cotton has an intact cellulosestructure, with lower weight loss and strength loss. The fabric gives better wetting andpenetration properties, making subsequent bleach process easy and resultantly givingmuch better dye uptake. It also reduces environmental burden by reducing wastewater treatment.

MATERIAL & METHODS


Enzymatic scouring process can be applied to cellulosic fibres and their blends (forboth woven and knitted goods) in continuous and discontinuous processes. Whenenzymatic desizing is applied, it can be combined with enzymatic scouring. Theprocess can be applied using jet, overflow, winch, pad-batch, pad-steam and padrollequipment.

MATERIAL & METHODS


MATERIAL AND METHODS:

SUBSTRATE:

100 % cotton woven greige fabric with: GSM of 136. Warp/weft:60/58 Count :20/s

CONDITIONING:

All the samples were conditioned, before and after each pre-treatment process, in adesicator for 24hrs containing an aqueous solution of sodium nitrite NaNO2 formaintaining the standard humidity constant i.e. 65 humidity.

EQUIPMENT SPECIFICATIONS:

METHOD:-

100 % cotton woven greige fabric with 136g/m2 weight was used for experiments andall pretreatment processes of this fabric were realized in an ultrasonic tank with avolume of 28 l. The frequency of the ultrasound waves generated by the sonicatorplate was 35 kHz.

Enzymatic pretreatment of fabrics was carried out with/without the use of ultrasonicenergy as shown in the table:

MATERIAL AND METHODS


Pre Treatment Through Enzymes

Without Ultrasonic With Ultrasonic

a)

EnzymeticDesizing

Bio Scouring

Bleaching

EnzymeticDesizing

Bio Scouring

Bleaching

b)

EnzymeticDesizing

Bio Scouring+

Bleaching

EnzymeticDesizing

Bio Scouring+

Bleaching

c)

EnzymeticDesizing

+Bio Scouring

Bleaching

EnzymeticDesizing

+Bio Scouring

Bleaching

d)

EnzymeticDesizing

+Bio Scouring

+Bleaching

EnzymeticDesizing

+Bio Scouring

+Bleaching

DESIZING


DESIZING:

Desizing was carried out by the following two processes:1. Exhaust Process.2. Pad-Batch Process.

1. EXHAUST PROCES:

Desizing Recipe

L:R 1:10Bactosol PHC HC liq 0.3g/lHostapal UH (wetting agent) 1.0g/lSirrix 2UD (seq. agent) 0.5g/lpH 5.5

Grey Fabric

Desizing at70oC

Samples were treated for different time

10min 15min 20min 25min 30min

Wash at95oC for 5min

without Ultrasonic Energy with Ultrasonic Energy

DesizingTime

(minutes)

wt. b/fdesizing

(gm)

wt. a/fdesizing

(gm)

wt.loss(%)

Tegewa wt. b/fdesizing

(gm)

wt. a/fdesizing

(gm)

wt.loss(%)

Tegewa

10 4.43 4.17 5.86 2 5.85 5.47 6.40 315 5.85 5.48 6.30 3-4 6.60 6.23 6.70 4-520 5.70 5.33 6.50 4 6.58 6.13 6.80 625 6.52 6.09 6.60 5 4.27 3.97 7.00 730 5.75 5.33 7.3 6-7 6.52 6.00 7.9 8-9

DESIZING


2. Pad-Batch Process:

Desizing Recipe

Pick-up 90%Bactosol PHC HC liq 0.5g/lHostapal UH (wetting agent) 3.0g/lSirrix 2UD (Seq. agent) 1.0g/lpH 5.5

Grey Fabric

Pad the fabric(at room temperature)

with 90% pick up

After padding the padded samples were batched for following different time

15min 30min 45min 60min

Wash at95o/95o/95o/60oC

without Ultrasonic Energy with Ultrasonic Energy

BatchingTime

(minutes)

wt. b/fdesizing

(gm)

wt. a/fdesizing

(gm)

%wt.loss

Tegewa wt. b/fdesizin

g(gm)

wt. a/fdesizin

g(gm)

%wt.loss

Tegewa

15 4.26 4.02 5.63 2 4.39 4.12 6.15

3

30 2.75 2.58 6.1 3 5.70 5.32 6.6 4-545 6.52 6.09 6.6 4 6.65 6.19 7.0 660 5.50 5.09 7.4 5 5.7 5.26 7.7 7120 6.50 6.0 7.6 6-7 5.8 5.33 8.1 8-9

BIO-SCOURING


Bio-Scouring:

Bio Scouring Recipe

L:R 1:10Scourzyme L 0.5g/lHostapal UH (wetting agent) 3.0g/lSirrix 2UD (Seq. agent) 1.0g/lpH 9.0

Desized Fabric

Treated with Scourzyme& Hostapal UH

at 55oC for 20min

Add Sirrix 2UD andraise the temp. to 85oC

Treated at 85oCfor 10min

Washed at95o/95o/95o/60o

Without Ultrasonic Energy With Ultrasonic Energy

Weight loss Capilary(cm) Weight loss Capilary

(cm)wt. of

desizedfabric

wt. ofscouredfabric

% wt.loss

wt. ofdesizedfabric

wt. ofscouredfabric

% wt.loss

5.80 5.60 3.50 4.0 5.67 5.45 3.8 4.55.67 5.47 3.52 4.5 6.30 6.06 3.8 4.55.80 5.60 3.44 4.0 5.85 5.62 3.9 4.7

BLEACHING


BLEACHING:

Bleaching Recipe

L:R 1:10H2O2 7.0%Sirrix Antox (seq. agent) 1.0%NaOH(solid) 2.0g/lHostapal UH (wetting agent) 1.0%Stabilizer Sifa 1.0%pH 9.0

ScouredFabric

Treated at 95oCFor 45min

With above recipe

Washed at95o/95o/95o/60oC


Weight loss Capilary(cm) Whiteness Weight loss Capilary

(cm) Whiteness

wt. ofscouredfabric

wt. ofbleached

fabric

%wt.loss

wt. ofscouredfabric

wt. ofbleached

fabric

%wt.loss

5.5 5.45 0.9 4.5 61 6.0 5.93 1.2 5.5 725.05 5.0 1.0 4.5 59 5.10 5.03 1.3 5.5 715.10 5.04 1.1 4.5 60 5.05 4.99 1.4 5.5 70

DESIZING & BIO SCOURING


DESIZING & BIO-SCOURING:

Recipe

L:R 1:10Bactosol PH liq 1.0g/lScourzyme L 6.0g/lHostapal UH (wetting agent) 1.0g/lSirrix Antox (seq. agent) 1.0g/l

Grey Fabric

Treated with Bactosol,Scourzyme & Hostapal

At 55oC for 20 min

Add Sirrix and raisethe temp. to 85oC

Treated at 85oCFor 10min

Washed at95/95/95/60oC


Weight loss Capilary(cm) Tegewa Weight loss Capilary

(cm) Tegewa

wt. ofscouredfabric

wt. ofbleached

fabric

%wt.loss

wt. ofscouredfabric

wt. ofbleached

fabric

%wt.loss

6.22 5.66 9.0 4.5 8 6.22 5.58 10.28 5 97.65 6.96 9.0 4.5 8 7.64 6.90 9.7 5 97.52 6.82 9.3 4.5 8 7.68 6.93 9.7 5 9

SOLOMATIC BLEACHING


SOLOMATIC BLEACHING:

Recipe

L:R 1:10Scourzyme L 6.0g/lH2O2 7.0g/lNaOH(solid) 2.0g/lHostapal UH (wetting agent) 1.0%Stabilizer Sifa 1.0%Sirrix Antox (seq. agent) 1.0%

Desized Fabric

Treated with Scourzyme& Hostapal UH

at 55oC for 15min

Add Sirrix, H2O2, NaOH,Stabilizer and

raise the temp. to 90oC




Weight loss Capilary(cm) Whiteness Weight loss Capilary

(cm) Whiteness

wt. ofdesizedfabric

wt. ofbleached

fabric

%wt.loss

wt. ofdesizedfabric

wt. ofbleached

fabric

%wt.loss

5.62 5.40 3.9 4 56 5.18 4.96 4.2 4 615.72 5.48 4.1 4 54 5.52 5.28 4.3 4 635.68 5.45 4.0 4 57 5.61 5.37 4.2 4 62.7

COMBINED DESIZING, BIO-SCOURING & BLEACHING


COMBINED DESIZING, BIO-SCOURING & BLEACHING:

Recipe

L:R 1:10Bactosol PHC liq 1.5g/lScourzyme L 6.0g/lH2O2 7.0g/lNaOH(solid) 2.0g/lHostapal UH (wetting agent) 1.0%Stabilizer Sifa 1.0%Sirrix Antox (seq. agent) 1.0%

Grey Fabric

Treated with Bactosol,Scourzyme

& Hostapal UHat 55oC for 15min

Add Sirrix, H2O2, NaOH,Stabilizer and

raise the temp. to 90oC




Weight loss Capilary(cm)

Tegewa Whiteness Weight loss Capilary

(cm)Tegewa White

ness

wt. ofGreyfabric

wt.of

Bleached

%wt.loss

wt. ofGreyfabric

wt.of

Bleached

%wt.loss

7.65 6.96 9.0 3 8 52 7.64 6.90 9.7 4 9 586.33 5.74 9.3 3.5 9 51 7.52 6.75 10.2 4 9 59

RESULTS & DISCUSSION


RESULTS & DISCUSSIONS:

The effect of ultrasonic energy on the desizing:

Results obtained from trials, desizing by exhaust process, realised with 0.3 g/lbactosol (amylase) in order to observe the effect of ultrasonic energy on the desizingdegree and wettability are shown in Figure 1. Both the desizing degrees andwettability values of the trials realised in an ultrasonic medium with the use of 0.3 g/lbactosol (amylase) were high with regard to conventional processing where ultrasonicenergy is not applied. For example, the desizing degree in 25 minutes was 7 when USwas applied, and it was only 5 when US was not applied. In the same way, thewettability value was 3.5 cm with US, and it was only 2.5 cm without US.

Wettability with Ultrasound Wettability without UltrasoundDesizing Degree with Ultrasound Desizing Degree without Ultrasound

Figure 1: Desizing by Exhaust Process

0

1

2

3

4

5

6

7

8

9

0

1

2

3

4

5

6

10min, Desizing 15min, Desizing 20min, Desizing 25min, Desizing 30min. Desizing



When the results obtained from trials, desizing by pad batch process, realised with 0.5g/l bactosol (amylase) in order to observe the effect of ultrasonic energy on the desiz-ing degree and wettability are shown in Figure 2. Both the desizing degrees andwettability values of the trials realised in an ultrasonic medium with the use of 0.5 g/lbactosol (amylase) were high with regard to conventional processing where ultrasonicenergy is not applied. For example, the desizing degree, of sample batched for 30minutes, was 7 when US was applied, and it was only 2.5 when US was not applied.In the same way, the wettability value was 4.5 cm with US, and it was only 2.5 cmwithout US.

Wettability with Ultrasound Wettability without UltrasoundDesizing Degree with Ultrasound Desizing Degree without Ultrasound

Figure 2: Desizing by Pad Batch Process

All these desizing trials show us that the presence of ultrasound in the processingmedium increases the effect of bactosol (amylase) enzyme. The reason for this isultrasonic energy increasing the efficiency of amylase enzyme by giving theenzymatic solution a mechanical movement and thus supporting mass (enzyme mol-ecules) transfer into the fibre.

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The effect of ultrasonic energy on bio-scouring:

Results obtained from trials, realised with 5.0 g/l scourzyme (pectinase) in order toobserve the effect of ultrasonic energy on the wettability are shown in Figure 3. Thewettability values of the trials realised in an ultrasonic medium with the use of 5.0 g/lscourzyme (pectinase) were high with regard to conventional processing whereultrasonic energy is not applied. For example, the wettability value was 5.5 cm withUS, and it was only 4.0 cm without US.

Wettability with Ultrasound Wettability without Ultrasound

Figure 3: Bio-Scouring with and without ultrasonic energy

The reason for achieving such good results in such a short time with ultrasonic energyis thought to be the efficient cleaning of the waxes and starch which give the fabric ahydrophobic character with the aid of sound waves.



The effect of ultrasonic on bleaching:

Results obtained from trials, realised with 7.0 ml/l H2O2 (50%) in order to observe theeffect of ultrasonic energy on the wettability are shown in Figure 4. The wettabilityvalues of the trials realised in an ultrasonic medium with the use of 7.0 ml/l H2O2(50%) were high with regard to conventional processing where ultrasonic energy isnot applied. For example, the wettability value was 6.0 cm with US, and it was only4.5 cm without US and whiteness was 70.49 with US, and it was 60.21 without US.

Wettability with Ultrasound Wettability without UltrasoundWhiteness with Ultrasound Whiteness without Ultrasound

Figure 4: Bleaching with and without ultrasonic energy



The effect of ultrasonic energy on combined desizing and bio-scouring:

Results obtained from trials, desizing by exhaust process, realised with 1.0 g/lbactosol (amylase) and 6 g/l Scourzyme (pectinase) in order to observe the effect ofultrasonic energy on the desizing degree and wettability are shown in Figure 5. Boththe desizing degrees and wettability values of the trials realised in an ultrasonicmedium with the use of 1.0 g/l bactosol (amylase) and 6g/l pectinase were high withregard to conventional processing where ultrasonic energy is not applied.

Wettability with Ultrasound Wettability without UltrasoundDesizing degree with Ultrasound Desizing degree without Ultrasound

Figure 5: Desizing and Bio-Scouring with and without ultrasonic energy



The effect of ultrasonic energy on combined bio-scouring and bleaching:

Results obtained from trials, bio-scouring and bleaching by exhaust process, realisedwith 6 g/l Scourzyme (pectinase), 7 ml/l H2O2 (50%) and 2g/l NaOH in order toobserve the effect of ultrasonic energy on the whiteness and wettability are shown inFigure 6. Both the whiteness and wettability values of the trials realised in anultrasonic medium with the use of 6g/l pectinase and 7 ml/l H2O2were high withregard to conventional processing where ultrasonic energy is not applied.


Figure 6: Bio Scouring and Bleaching with and without ultrasonic energy



The effect of ultrasonic energy on combined bio-scouring and bleaching:

Results obtained from trials, combined desizing, bio-scouring and bleaching byexhaust process, realised with1.5g/l Bactosol (amylase), 6 g/l Scourzyme (pectinase),7 ml/l H2O2 (50%) and 2g/l NaOH in order to observe the effect of ultrasonic energyon the whiteness and wettability are shown in Figure 6. Both the whiteness andwettability values of the trials realised in an ultrasonic medium with the use of 1.5g/lBactosol (amylase), 6g/l pectinase and 7 ml/l H2O2were high with regard toconventional processing where ultrasonic energy is not applied.


Figure 7: Combined Desizing, bio-Scouring and bleaching with and withoutultrasonic energy



Breaking strengths of treated fabrics

The breaking strength is also another important parameter related with the treatmentconditions. In order to investigate the effect of pretreatment processes and ultrasoundon the strengths of fabrics, the most effective treatment conditions from the trial planwere selected and the strength and weight changes of these fabrics were examined.All these testing methods are followed by the standard of ASTMD2261.

Breaking strengths are shown in the Table 1 below:

ParameterGreigefabric Desized fabric Bio- scoured fabric Bleached fabric

WithoutUS

WithUS

WithoutUS

WithUS

WithoutUS

WithUS

Tearstrength

(Kg)3.59 3.05 2.75 1.84 1.68 1.61 1.58

Table: 1

SUMMARY


SUMMARY:

When ultrasound is applied in desizing, realized with amylase enzyme, the desizingdegree and fabric wettability are distinctively higher than the processing withoutultrasound. This is achieved by making use of the mechanism of ultrasound to activatethe enzymes with big molecules and the property of supporting the double-sided masstransfer from liquor to fabric, and from fabric to liquor. Hence, the existence ofultrasound in the processing medium increases the efficiency of the enzymes.

When ultrasound is applied in bio-scouring, realized with pectinase enzyme, theresults are distinctively higher than the processing without ultrasound. The reason forachieving such good results in such a short time with ultrasonic energy is thought tobe the efficient cleaning of the waxes and starch which give the fabric a hydrophobiccharacter with the aid of sound waves.

Similarly the results are distinctively higher when the ultrasound is applied inbleaching, combined desizing & bio-scouring, solomatic bleaching & combineddesizing, bio-scouring and bleaching in comparison to processing without ultrasound.

Mass transfer in textile pretreatment and finishing processes is usually only on alimited levels. For this reason, these processes necessitate long processing times andbig amounts of water, chemical and energy consumption. The efficiency of wetfinishing processes is increased by increasing the mass transfer towards to the innerparts of the textile material.

CONCLUSION & RECOMMENDATIONS


CONCLUSION:

Enzymatic bio-processing has several critical shortcomings that impede its wideacceptance by industries: Expensive processing cost and slow reaction rates. Ourresearch found that the introduction of low energy, uniform ultrasound field intovarious enzyme processing solutions greatly improved their effectiveness bysignificantly increasing their reaction rate.

It has been established that the following specific features of combined enzyme/ultrasound bio-pre treatment are critically important:

Cavitation effects caused by ultrasound greatly enhance the transport ofmacromolecule of enzyme towards substrate surface. Mechanical impacts, produced by collapse of cavitation bubbles, provide animportant benefit of opening up the surface of substrates to the action of enzymes. In water, maximum effects of cavitation occur at 50o C, which is the optimumtemperature for many enzymes. The combined effect of heat, ultrasonic waves and pressure may be used forinactivation of certain thermostable enzymes.

The effect of ultrasound power is an important technique increasing the mass transfertowards the textile material, and in this way it is possible to eliminate thedisadvantages given above without affecting the strength of the fabric.

RECOMMENDATIONS:

After observing the results, obtained from the bio pre-treatment of cotton fabric in thepresence of ultrasonic energy, following points are recommended for achieving moreefficient results:

For optimum results sonication frequency should be lower i.e. from 20-25KHz,instead of higher frequencies i.e. 35KHz or higher. The combined effect of heat, ultrasonic waves and pressure may be used forinactivation of certain thermostable enzymes, therefore high temperatures andsonication frequencies are not recommended.

REFRENCES


REFERENCES:

1. C. Karaboğa, A. E. Körlü, K. Duran, M. İ. Bahtiyari (Ege University Department ofTextile Engineering, Izmir, Turkey): Use of Ultrasonic Technology in EnzymaticPretreatment Processes of Cotton Fabrics.

2. Yasui K., Tuziuti T., Iida Y.; Ultrasonics Sonochemistry Vol. 12 (2005), pp. 43–51.

3. Dr. Niaz, A., et al, Bioscouring of Cellulosic Textiles, Pakistan Textile Journal,(August 2009), page 40.

4. Muhammad Ayaz Shaikh, Asst. Professor, College of Textile Engineering,SFDAC: Enzymes: A revaluation in textile processing, Pakistan Textile Journal,(April 2010), page 48.

5. Nazakat Ali, Mehran University of Engineering and Technology: Use of ultrasoundfor intensification of enzymatic bio-processing.

6. Aravin Prince P lecturer JKK Muniraja Polytechnic, Gobi Tamil Nadu: ultrasonicassisted wet processing. Indian Textile Journal.

7. Shukla, R., Sharma, U. and Kulkarni, S. (2000) Enzymes and Their Use inTextile Processes. Colourage 2, 19–24.

8. Akalin M., Merdan N., Kocak D., Usta I.; Ultrasonics Vol. 42 (2004) pp. 161–164.

9. Vouters M., Rumeau P., Tierce P., Costes S.; Ultrasonics Sonochemistry Vol. 11(2004) pp. 33–38.

10. Anita K. Losonczi, Bioscouring of Cotton Textiles, Ph.D. Thesis, BudapestUniversity of Technology and Economics, (2004)

use of us energy in enzymatic pre treatment of cotton fabric

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