comparative study on removal of heavy metals from textile ... - IJASER

International Journal of Advanced Science and Engineering Research Volume: 2, Issue: 2, June 2017

www.ijaser.in ISSN: 2455-9288

COMPARATIVE STUDY ON REMOVAL OF HEAVY METALS FROM TEXTILE INDUSTRY WASTEWATER USING VARIOUS ADSORBENT A.THARANI1, R.HARISH2*, P.MAHESHKUMAR3, S.RAMESH4 1 2

PG. Student, Department of Environmental Engineering, Gnanamani college of Engineering, Namakkal. Assistant professor, Department of Civil Engineering, Dhaanish Ahamed Institute of Technology, Coimbatore. 3 Assistant professor, Department of Civil Engineering, K.S Rangasamy college of Technology, Namakkal. 4 Professor, Department of Civil Engineering, K.S Rangasamy college of Technology, Namakkal.

*Corresponding author [email protected] Abstract -

The most important class of pollutants are the effluents (dyes) which are disposed directly to the river from the textile industries. Disposal of the effluents into the water streams or precious water resource must be avoided. However there are various treatment methods before disposal, which will not be effective in the removal of heavy metals. Adsorption is recognized as an effective and economic method for low concentration heavy metal wastewater treatment. In the adsorption process numerous adsorbents are available. The adsorbents used are banana peel, activated carbon produced from coconut shell. The adsorption process is done using column chromatography. In this project a comparative study is done in order to make a comparison between the removal efficiency of the various adsorbents. Some of the heavy metals which are present in even smaller amount will cause a greater pollution. This project is based on the various adsorbents which have greater influencing in the removal of heavy metals, namely copper and chromium. The dosage of adsorbents is about 10 grams, 15 grams, 20 grams which will create a situation of removing heavy metals. The adsorption process is done at the room temperature for about an hour for each adsorbent. The adsorption process is started with the initial concentration of 10 gram of each adsorbent and then gradually increased based on the removal percentage. At the end 25 gram of dosage is given beyond that which produces which produces heavy metals. I. INTRODUCTION

Saving water to save the planet and to make the future of mankind safe is what we need now. With the growth of mankind, society, science, technology our world is reaching to new high horizons but the cost which we are paying or will pay in near future is surely going to be too high. Among the consequences of this rapid growth is environmental disorder with a big pollution problem. Anthropogenic activities have caused a great harm to the quality of our lifeline, i.e. water. Because of fast depletion of the freshwater resources, there seems to be a crisis of the same. Water pollution is a global concern and, it is the high time that we realize the gravity of the situation. A.ADSORPTION PRINCIPLES Adsorption is a process that occurs when a gas or liquid solute accumulates on the surface of a solid or a liquid, forming a molecular or atomic film. In other words, adsorption is the adhesion of atoms, ions, bio molecules or molecules of gas, liquid, or dissolved solids to a surface and this process creates a film of the adsorbate (the molecules or atoms being accumulated) on the surface of the adsorbent. The exact nature of the bonding depends on the details of the species involved, but the adsorption process is generally classified as follows:

Copyright © 2017 by the Authors. This is an open access article distributed under the Creative Commons Attribution License, which permits Unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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A.1 PHYSISORPTION It is a type of adsorption in which the adsorbate adheres to the surface through Vander Walls (weak intermolecular) interactions. A.2 CHEMISORPTION It is a type of adsorption whereby a molecule adheres to a surface through the formation of a chemical bond. B.INTRODUCTION ABOUT DYES Dyes are an important class of pollutants and can even be recognized by human eyes. Dyes have high structural diversity and can be classified in many ways. Some properties of dyes are based on their usage and can be broadly classified as follows. Acid dyes, Basic dyes, Direct dyes, Disperse dyes, Mordant dyes, Sulphur dyes, Reactive dyes, Solvent dyes, Vat dyes C.PROPERTIES OF ADSORBENTS The materials which are used for this process is the adsorbents. Following are the adsorbents.  Banana peel  Fly ash  Activated carbon C.1 BANANA PEEL Musa sapientum which is commonly called banana is a herbaceous plant of the family MusaceaeThe stem which is also called pseudostem produces a single bunch of banana before dying and replaced by new pseudostem. The fruit grows in hanging cluster, with twenty fruits to a tier and 3 – 20 tiers to a bunch. Its role to regulate blood pressure has been associated with the high content of potassium. Banana helps in solving the problem of constipation without necessary resorting to laxatives. Banana can cure heart burns stress, strokes, ulcers and many other ailments. C.2 FLY ASH Fly ash is one of the residues created during the combustion of coal in coal-fired power plants. Fine particles rise with flue gasses and are collected with filter bags or electrostatic precipitators. Fly ash is a waste by-product material that must be disposed of or recycled. C.3.ACTIVTED CARBON Activated carbon (AC) as many known as a solid, porous, black carbonaceous material and tasteless. Marsh defined AC as a porous carbon material, usually chars, which have been subjected to reaction with gases during or after carbonization in order to increase porosity. AC is distinguished from elemental carbon by the removal of all non-carbon impurities and the oxidation of the carbon surface. AC is an organic material that has an essentially graphitic structure. D. HEAVY METALS The term “heavy metals” refers to any metallic element that has a relatively high density and is toxic or poisonous even at low concentration. Heavy metals include lead (Pb), cadmium (Cd), zinc (Zn), mercury (Hg), arsenic (As), silver (Ag) chromium (Cr), copper (Cu) iron (Fe), and the platinum group elements. Copyright © 2017 by the Authors. This is an open access article distributed under the Creative Commons Attribution License, which permits Unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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D.1 MERCURY Readily absorbed via respiratory tract. Inflammation of mouth and gums, swelling of salivary glands, excessive flow of saliva, loosening of teeth; kidney damage; muscle tremors, jerky gait, spasms of extremities; personality changes, discouragement, depression, irritability, nervousness, dementia, loss of motor coordination. Effects on wildlife can include reduced fertility, damaged kidneys, slower growth and development, abnormal behaviour and even death. Whales and dolphins may also be at high risk from mercury exposure. D.2. CADMIUM Target organs are the liver, placenta, kidneys, lungs, brain, and bones. Renal disfunction. Biopersistent and once absorbed by an organism remains resident for many years. Cadmium is also toxic to plants, animals and micro-organisms. Cadmium accumulates mainly in the kidney and liver of vertebrates and in aquatic invertebrates and algae (UNEP 2008b). D.3 COPPER Copper toxicity is a much overlooked contributor to many health problems; including anorexia, fatigue, premenstrual syndrome, depression, anxiety, liver and kidney damage, migraine headaches, allergies, childhood hyperactivity and learning disorders. D.4 IRON Ingestion accounts for most of the toxic effects of iron because iron is absorbed rapidly in the gastrointestinal tract. Lead exposure in utero, in infancy and childhood may result in low birth rate, anaemia, neurological impairment, IQ deficits, renal alterations, colic, growth retardation or impaired metabolism of vitamin D. D.5 LEAD Target organs are the bones, brain, blood, kidneys, and thyroid gland. Accounts for most of the cases of paediatric heavy metal poisoning . Lead poisoning is the leading environmentally induced illness in children E. TEST FOR HEAVY METALS Heavy metals test is done using Atomic Absorption Spectrophotometer. The following picture indicates the atomic absorption spectrophotometer. Atomic Absorption Spectroscopy (AAS) is a widely used technique for determining a large number of metals. In the most common implementation of AAS, an aqueous sample containing the metal analyte is aspirated into an air-acetylene flame, causing evaporation of the solvent and vaporization of the free metal atoms. This process is called atomization. The availability of a spectrometer equipped with a lamp turret (allowing several line sources to be used in sequential fashion) will facilitate the measurement of multiple metals in the sample. F. CHEMICAL EXPERIMENTS F.1 DETREMINATION OF pH PH = - log [H+] The fresh waste water is generally acidic in nature nearly 5 to 6. But as time passes, its PH tends to fall due to production of acids by bacterial action in anaerobic processes. To be more exact, pH is the measurement of the hydrogen ion concentration, [H+]. Every aqueous solution can be measured to determine its pH value. This value ranges from 0 to 14 pH. Values below 7 pH exhibit acidic properties. Values above 7 pH exhibit basic (also known as caustic or alkaline) properties. Copyright © 2017 by the Authors. This is an open access article distributed under the Creative Commons Attribution License, which permits Unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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Since 7, pH is the center of the measurement scale, it is neither acidic nor basic and is, therefore, called "neutral." pH is defined as the negative logarithm of the hydrogen ion concentration. This definition of pH was introduced in 1909 by the Danish biochemist, Soren Peter Lauritz Sorensen. It is expressed mathematically as: pH = -log [H+] where: [H+] is hydrogen ion concentration in ml/L The pH value is an expression of the ratio of [H+] to [OH-] (hydroxide ion concentration). Hence, if the [H+] is greater than [OH-], the solution is acidic. Conversely, if the [OH-] is greater than the [H+], the solution is basic. At 7 pH, the ratio of [H+] to [OH-] is equal and, therefore, the solution is neutral. Environmental significance of p H pH (6.5 to 8.5) has no direct effect on health however a lower value below 4 will produce sour taste and higher value above 8.5 a bitter taste. Higher values of p1-I have scale formation in water heating operators and also reduce the germicidal potential of chlorine. High pH induces the formation of trihalomethanes which are causing cancer in human beings. pH below 6.5 starts corrosion in pipes, thereby releasing toxic metals such as zinc, lead, cadmium & copper etc., According to BIS water for domestic consumption should have pH between 6.5 to 8.5 F.2 TURBIDITY Turbidity is caused by particles suspended or dissolved in water that scatter light making the water appear cloudy or murky. Particulate matter can include sediment - especially clay and silt, fine organic and inorganic matter, soluble coloured organic compounds, algae, and other microscopic organisms. In the Minnesota River, sediment is the primary contributor to turbidity. In a shallow lake in August, it may be algae. In a northern Minnesota lake it may be tannin released by the breakdown of organic material. Environmental Significance of turbidity: Turbidity is objectionable because of a. Aesthetic considerations and b. Engineering considerations F.3 TOTAL DISSOLVED SOLIDS Total dissolved solids are the main parameters that would prove fruitful in experimental analysis. The determination of dissolved solids is essential in analysing the pollution load. The amount of dissolved solids present in water is a consideration for its suitability to domestic use. A value of 1500 mg / l is considered as the permissible level for total dissolved solids. The adverse effects caused by the excessive TDS are to affect the colour and taste of the sample, cause foaming and scaling, and accelerate corrosion. CALCULATION Total dissolved solids (mg/l) =

mg/l


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F.4 DISSOLVED OXYGEN Dissolved oxygen (DO) is one of the most important indicators of the quality of water for aquatic life. It is essential for all plants and animals. Oxygen availability throughout the year is influenced by other chemicals present in the water, biological processes, and temperature. A dissolved oxygen test measures the amount of oxygen dissolved in the water. A dissolved oxygen measurement, however, does not measure the amount of dissolved oxygen the water is capable of holding at the temperature at which it was tested. Warmer water is capable of holding less dissolved oxygen than colder water. When water holds the entire DO it can hold at a given temperature, it is said to be 100 percent saturated with oxygen. If water holds half as much oxygen as it can hold at a given temperature, it is 50 percent saturated. Most living organisms require oxygen for their basic metabolic processes. Since the existence of plants also depends on the availability of light, the oxygen-producing processes occur only near the surface or in shallow waters. Photosynthesis of aquatic plants releases oxygen into the water. Oxygen is also dissolved in water through diffusion and surface turbulence. Oxygen is poorly soluble in water, roughly 10 parts per million (ppm) at 0-2 ºC compared to almost 1700 ppm for carbon dioxide at the same temperature. When oxygen levels in the water fall below 3-5 ppm, most fish and marine organisms are stressed and cannot survive. F.5 CHEMICAL OXYGEN DEMAND (COD) Oxygen demand or oxygen deficiency caused by organic contaminants by consuming water dissolved oxygen. The oxygen required to oxidize the organic matter present in a given waste water can be theoretically computed, if the organics present in waste water are know. F.6 BIOCHEMICAL OXYGEN DEMAND Biochemical Oxygen Demand (BOD) is defined as the amount of oxygen required by bacteria for stabilizing decomposable organic matter in water under aerobicconditions. BOD is expressed in milligram per litre G. RESULTS OBSERVED FROM ATOMIC ABSORPTION SPECTROSCOPY G.1 COPPER Initial concentration =

3.157 mg / litre.

S.NO

ADSORBENT CONCENTRATION

BANANA PEEL (mg/l)

FLY ASH (mg/l)

ACTIVATED CARBON(mg/l)

1

10 gram

2.698

2.475

2.226

2

15 gram

2.055

1.920

1.698

3

20 gram

1.628

1.664

1.422

4

25 gram

1.628

1.664

1.422

The above table shows that the activated carbon has more efficiency in removing the carbon. The permissible limit of carbon for waste water is 1.5 mg/l. This is achieved by adding 20 gm of activated


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carbon and above the certain limit of usage. After that the dosage of 25 grams of adsorbent the conditions prevails the same. G.2 CHROMIUM Initial concentration =

0.029 mg / litre

S.NO

ADSORBENT CONCENTRATIO N

BANANA PEEL (mg/l)

FLY ASH (mg/l)

ACTIVATED CARBON(mg/l)

1

10 gram

0.022

0.018

0.012

2

15 gram

0.015

0.011

0.009

3

20 gram

0.010

0.010

0.003

4

25 gram

0.010

0.010

0.003

The above table shows that the usage of activated carbon adsorbent is again proven to be more efficient in removing the chromium. The permissible limit of chromium prescribed by the IS codes is 0.005 mg/l and that is achieved by adding 20 grams of activated carbon G.3 TURBIDITY G.3.1 INITIAL TURBIDITY OF EFFLUENT SAMPLE DETAILS

READING ON SCALE

TURBIDITY (NTU)

1

65

65

G.4 TOTAL DISSOLVED SOLIDS G.4.1 INITIAL TOTAL DISSOLVED SOLIDS FOR EFFLUENT OBSERVATION: SAMPLE DETAILS

Textile industry waste water

VOLUME OF SAMPLE (ml) 20

INITIAL WEIGHT OF DISH (mg) - B 27531

FINAL WEIGHT OF DISH (mg) - A 27490


TOTAL DISSOLVED SOLIDS (mg/l) 2050

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CALCULATION Total dissolved solids (mg/l) = = = 2050 mg/l G.4.2 TOTAL DISSOLVED SOLIDS FOR THE EFFLUENT TREATED

G.5

ADSORBENTS USED

SAMPLE 1(10 gm)

SAMPLE 2(15gm)

SAMPLE 3(20gm)

Banana peel

50

48

45

Activated carbon Fly Ash

46

44

40

47

45

42

DISSOLVED OXYGEN Volume Of Sample (Ml) 20

Initial Bod Of The Sample (Mg/L) 15.0

Final Bod Of Sample( Mg/L)

Initial Bod Of The Blank (Mg/L)

16.5

0

Final Bod Of The Blank (Mg/L) 0

5 Days Bod At 20 C (Mg/L) 11.25

Initial dissolved oxygen of effluent = 36.8mg/l DISSOLVED OXYGEN CONTENT FOR THE EFFLUENT TREATED

ADSORBENTS USED

Banana peel Activated carbon Fly Ash

SAMP LE 1(10 gm) 1300 1100 1200

SAMPLE 2(15gm)

SAMPLE 3(20gm)

1100 1000 1100

1000 1000 1100


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G.6 CHEMICAL OXYGEN DEMAND G.6.1 CHEMICAL OXYGEN DEMAND FOR THE EFFLUENT TREATED Sample Details

Waste Water Effulent

Volu me Of Sam ple Take n 20

Initial Burette Readin g(Ml)

Final Burette Reading(M l)

Volume Of Fe(Nh4)2 (So4)2 Added In Ml

0

6.0

1.43

Cod Of The Samp le (Mg/ L) 9.2

G.7 BIOCHEMICAL OXYGEN DEMAND G.7.1 INITIAL BOD OF EFFLUENT CALCULATION D0 = 15.0 D5 = 16.5 C0 = 0 C5 = 0 D.O depletion of dilution water = C0-C5 =1.5 D.O depletion of dilution sample = D0-D5=1.5 BOD at 20 C of the samp = = 11.25mg/l G.7.2 BOD FOR EFFLUENT TREATED ADSORBE NTS USED

SAMPLE 1(10 gm) mg/l

Banana peel Activated carbon Fly Ash ADSORBENTS USED Banana peel Activated carbon Fly Ash

36.8 34.5

SAMPL E 2(15gm) mg/l 35.2 33.1

SAMPL E 3(20gm) mg/l 34 32.8

35.6

34.8

34.2

SAMPLE 1(10 gm) 5.9 5.1 5.3

SAMPLE 2(15gm) 5.6 5.1 5.4

SAMPLE 3(20gm) 5.6 5.0 5.4

. RESULT AND DISCUSSION H.1 PERCENTAGE EFFICIENCY OF REMOVAL OF COPPER: a) Banana Peel of 10 grams: Efficiency= =14.54% b)

Banana peel of 15 grams:


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H



Efficiency = = 35% c) Banana peel of 20 grams: Efficiency = d)

= 48.43%

Fly ash of 10 grams:

Efficiency

= = 21.6% Fly ash of 15 grams:

e)

ADSORBENT S USED Banana peel Activated carbon Fly Ash

SAMPL E 1(10 gm) 8.5 8.0

SAMPL E 2(15gm) 8.4 7.8

SAMPLE 3(20gm)

8.7

8.5

8.3

8.4 7.7

=39.18% Efficiency= f) Fly ash of 20 grams: Efficiency = =49% g) Activated carbon of 10 grams: Efficiency= =29.5% h) Activated carbon of 15 grams: Efficiency= =46.21% i) Activated carbon of 20 grams: Efficiency =

=55%

H.2 PERCENTAGE EFFICIENCY OF REMOVAL OF CHROMIUM: a) Banana Peel of 10 grams: Efficiency = = 24.14% Banana peel of 15 grams:

b) Efficiency

=


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= 48.3% c) Banana peel of 20 grams: Efficiency = = 65.52% d) Fly ash of 10 grams: Efficiency

=

= 38% e) Fly ash of 15 grams: Efficiency = = 62.1% f) Fly ash of 20 grams: Efficiency = g)

= 65.52%

Activated carbon of 10 grams:

Efficiency = = 58.62% h) Activated carbon of 15 grams: Efficiency= i) Activated carbon of 20 grams: Efficiency =

=69%

= 89.66%

2. CONCLUSION The project summarises the comparative study on removal of heavy metals from textile industry effluent using various adsorbents. There are numerous numbers of adsorbents namely rice husk, sludge, peel of citrus fruits, activated carbon, fly ash, etc., which have advantages in removing the heavy metals. We have selected three adsorbents for the comparative study which are Banana peel, Fly ash, Activated carbon. These are the adsorbents which are available in huge quantities. Banana, coconuts are those which are abundant in Tamil Nadu.

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3. Aksu Z. Application of biosorption for the removal of organic pollutants: a review. Process Biochem 2005; 40: 997 1026. 4. Crini G. Non-conventional low-cost adsorbents for dye removal: a review. Bioresour. Technol 2006; 97: 1061 1085. 5. Dapinder K, Bakshi KG, Gupta PS. Enhanced biodecolorization of synthetic textile dye effluent by Phanerochaete chrysosporium under improved culture conditions. World J. Microbial. Biotechnol 1999; 15: 507 509.


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