Study Of Biosorbtion Isotherms Biology Essay

Fabric industry is one of the most of import industries in Thailand. However effluent released from dye procedure create jobs to ecosystems and wellness of people nearby ( Boer et al, 2004 ; Saeed et al. , 2009 ) . Among industrial effluents, dye effluent from fabric and dyestuff industries is one of the most hard Waterss to handle. This is because dyes normally have a man-made and complex aromatic molecular construction, which makes them more stable and have hard to biodegrade. The dyes used in the fabric industries include several structural assortments such as acidic, reactive, basic, disperse, azo, diazo, anthraquinone based and metal complex dyes. The most normally used techniques for colour remotion include curdling, membrane engineerings, flocculation, ozonation, Fenton ‘s reactive, rearward osmosis, cucurbutyril, electrochemical debasement, active C. Although the above mentioned methods of physical and / or chemicals have been widely used, but whether there are limitations, such as high cost, construction of risky by-products and high energy intensive consumtion. Current accent on environmental preservation. Therefore the hunt for a new motion in the intervention of dye contaminated with one of them is the usage of biomass as a dye soaking up. The usage of fungous biomasses as biosorbents for remotion of assorted man-made dyes from assorted effluent ( Cing and Yesilada, 2004 ; Das et al. , 2006 ; Seyis and Subasioglu, 2008 ) was introduced because of its low cost and environmentally friendly comparative to the traditional physicochemical procedures ( Vijayaraghavan et al. , 2007 ) .

2. Aim

The survey of biosorbtion isotherms and kinetic theoretical account in effluent intervention is important as it provides valuable penetrations into the reaction, mechanism, and tracts of sorption reactions. Therefore, this survey was aimed to utilize the fungous biomass of white putrefaction Fungi, Lentinus strigosus in sorption man-made dyes. The surface assimilation isotherms and kinetic theoretical account equations were used to foretell the biosorption mechanism.

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3. Research Methodology

3.1. Beginning of fungus

The white putrefaction fungus, Lentinus strigosus, was obtained from Department of Agriculture, Ministry of Agriculture and Cooperative in Thailand. Stock civilization was maintained on Potato Dextrose Agar ( PDA ) at 4 & A ; deg ; C until usage.

3.2 Man-made dyes

Two types of dye: Remazol Brilliant Blue R ( RBBR ) and Remazol Black B ( RB5 ) were obtained from Dystar Thai Company Limited in Thailand.

3.3 Preparation of biomass

The fungus mycelium was grown on fresh PDA and incubated at room temperature ( 28 – 30 & A ; deg ; C ) for 5 yearss. Ten agar stoppers ( & A ; Oslash ; 5 millimeter from the border of a 5-day-old agar civilization ) of fungous biomass ( Lentinus strigosus ) were inoculated in 100 milliliters Potato Dextrose Broth ( PDB ) before incubating at room temperature ( 28 – 30 & A ; deg ; C ) with agitating for 7 yearss. After cultivation, the alive biomass was prepared by reaping and rinsing three times with distilled H2O. The dead biomass was prepared through the autoclaving at 121 & A ; deg ; C, 1 standard pressure for 20 min. These were ready to be used for farther experiments.

3.4 Analysis of man-made dyes

Concentrations of man-made dyes solution were determined utilizing a spectrophotometer ( JASCO V-530 UV/VIS spectrophotometer ) at 592 and 597 nanometer for RBBR and RB5, severally.

3.5 Biosorption experimental

The biosorption of man-made dyes was carried out in 250 milliliters Erlenmeyer flask incorporating 100 milliliter of dyes solution. To guarantee the equilibrium, the solution mixtures of 50 mgl-1 dye and 1.0 g of alive or dead biomass at pH 2.0 were incubated at 30 & A ; deg ; C with agitating rate of 150 revolutions per minute for 6 H on a rotary shaker. The experiments were performed in triplicate. The sum of dyes adsorbed per unit of alive or dead biomass ( mg dyes/g biomass biosorbent ) was determined utilizing the undermentioned look:

qeq = ( 1 )

Where

qeq = the equilibrium dyes uptake ( mg dyes/g biomass weight of alive or dead biomass )

V = the volume of dyes solution ( cubic decimeter )

Ci = the initial concentration of dyes in the solution ( mg l-1 )

C = the residuary concentration of dye in the solution at any clip ( mg l-1 )

M = the weight of alive or dead biomass ( g )

3.5.1 Sorption isotherm

Langmuir and Freundlich isotherm theoretical accounts were used in the survey of surface assimilation efficiency ( Arica and Bayramoglu, 2007 ; Rachna and Suresh, 2008 ) .

The Langmuir isotherm is based on the homogenous surface and monolayer surface assimilation, and is presented by the undermentioned equation:

qeq= ( 2 )

where

qmax = the maximal uptake capacities ( mg g-1 biosorbent )

Ceq = the equilibrium concentration ( mg l-1 solution )

B = the equilibrium invariable ( fifty mg-1 )

The Freundlich isotherm theoretical account is based on heterogenous surface and multilayer surface assimilation, and is presented by the undermentioned equation:

qeq= ( 3 )

where

KF, n = the Freundlich contants characteristic of the system

3.5.2 Sorption dynamicss

In the survey of sorption kinetic theoretical account, it is really of import to cognize the rate of surface assimilation for design and measure the adsorbent in taking the dyes in H2O. The kinetic surveies were carried out by carry oning batch biosorption experiments with different initial dyes concentrations. Samples were taken at different clip periods and analyzed for their dyes concentration. The pseudo-first-order Largergren and the pseudo-second order biosorption processes ( Zeroual et al. , 2006 ) were applied to the experimental information.

The first-order rate look of Largergren is shown in the undermentioned equation:

log ( qeq – qt ) = logqeq – k1, adt/2.303 ( 4 )

where

qeq = the sum of adsorbed dye at equilibrium ( mg g-1 )

qt = the sum of adsorbed dye on the biosorbent at clip T ( mg g-1 )

k1, ad = the rate invariable to Largergren first-order biosorption ( min-1 )

T = clip ( min )

The pseudo second-order kinetic rate equation is shown in the undermentioned equation:

t/q = 1/ ( K2, adq2eq ) + t/qeq ( 5 )

where

K2, ad = the rate invariable of second-order biosorption ( g mg-1 min-1 )

T = clip ( min )

3. Consequence

3.1 Biosorption of man-made dyes

In order to find the consequence of contact clip on the dyes sorption capacity of alive and dead biomass, both biosorbents were contacted with 50 mgl-1 dyes solution for assorted intervals runing between 20 min and 6 H at 30 & A ; deg ; C and pH 2. Fig.1 shows the consequence of contact clip on dyes sorption capacities of alive and dead fungous biomass. The rapid dyes sorption rate of RBBR and RB5 by both biomass occurred within the first 20 min. The sorption sum of RBBR and RB5 were 65.23 and 64.04 % , severally, by alive biomass, and 82.69 and 84.80 % , severally, by dead biomass. While the equilibrium of RBBR and RB5 sorption system were established in 90 and 120 min for dead and alive biomass severally.

Fig.1. Effect of contact clip on man-made dyes biosorption capacities of alive and dead fungous biomass

3.2 Sorption Isotherms

The surface assimilation isotherms indicate how the surface assimilation molecules distribute between the fungous biomass and dyes molecule when the surface assimilation procedure reaches an equilibrium province.

B

a

Fig. 2. Langmuir ( a ) and Freundlich ( B ) isotherms of RBBR and RB5 on alive and dead fungous biomass

Fig. 2 shows the Langmuir and Freundlich secret plans of RBBR and RB5 sorption onto fungous biomass. Table 1 shows the comparings between Langmuir and Freundlich isotherms. The experimental information fitted good with the Langmuir equation with every bit high correlativity coefficients ( r 2 ) as 0.999. Therefore, the dyes surface assimilation onto biomass was consistent with strong monolayer sorption. With Langmuir isotherms, the maximal surface assimilation capacities, qmax, of RBBR and RB5 were 16.12 and 15.15 milligram g-1, severally, by alive biomass, and 66.66 and 29.41 mg g-1 severally, by dead biomass.

Table 1. Isotherm theoretical account invariables and correlativity coefficients for surface assimilation of RBBR and RB5 by alive and dead fungous biomass

Biosorbent

Exp.

Langmuir isotherm theoretical account

Freundlich isotherm theoretical account

qmax ( mg g-1 )

qmax ( mg g-1 )

B ( fifty mg-1 )

r2

KF

1/n

r2

Alive biomass

RBBR

RB5

15.87 ± 0.58

14.85 ± 2.63

16.12

15.15

0.095

0.103

0.999

0.999

4.45

4.12

0.203

0.207

0.919

0.916

Dead biomass

RBBR

RB5

64.61 ± 0.80

28.39 ± 1.53

66.66

29.41

0.112

0.129

0.999

0.999

8.76

7.61

0.387

0.216

0.893

0.948

The Langmuir changeless surface assimilation value ( RL ) can be used to foretell whether a sorption system is favorable or unfavaourable. Since the RL values were within the nature of the surface assimilation procedure as given below table 2 ( Anjaneya et al. , 2009 ; Saeed et al. 2009 ) . The calculated by the undermentioned equation:

RL = ( 6 )

Where

B = the Langmuir invariable ( fifty mg-1 )

C0 = the initial dyes concentration ( mg l-1 )

Table 2. The Langmuir changeless surface assimilation value ( RL )

RLvalue

Nature surface assimilation procedure

RL & A ; gt ; 1

RL= 1

0 & A ; lt ; RL & A ; lt ; 1

RL= 0

Unfavorable

Linear

Favorable

Irreversible

The RL values for sorption of RBBR and RB5 are shown in Fig.3 and table 3. The mean values of RL at different initial dye concentration was found to be 0.066 and 0.061 severally, for alive biomass and 0.057 and 0.050 severally, for dead biomass severally, bespeaking that the surface assimilation of dyes by alive and dead fungus biomass was a favourable procedure.

Fig. 3 Value of Langmuir changeless surface assimilation ( RL ) for the sorption of RBBR and RB5 by alive and dead fungus biomass

Table 3. dyes diffusion rate parametric quantity and diffusion coefficient at different initial dye concentration

Initial dye concentration

The value of RL

RBBR

RB5

alive biomass

dead biomass

alive biomass

dead biomass

50

70

90

100

300

500

700

900

1000

0.1739

0.1307

0.1047

0.0952

0.0338

0.0206

0.0148

0.0115

0.0104

0.1515

0.1131

0.0902

0.0819

0.0289

0.0175

0.0125

0.0098

0.0088

0.1626

0.1218

0.0973

0.0884

0.0313

0.0190

0.0136

0.0106

0.0096

0.1342

0.0997

0.0793

0.0719

0.0251

0.0152

0.0109

0.0085

0.0076

3.3 Sorption dynamicss

To look into the sorption dynamicss of RBBR and RB5 by the fungous biomass, the invariables of dyes sorption were calculated utilizing the pseudo-first and pseudo-second order equation. For rating of RBBR and RB5 biosorption, the secret plan of ln ( qe – qt ) versus clip and t/qt versus clip were used and displayed as informations shown in Fig. 4 and Table 4.

a

B

Fig. 4 Pseudo-first dynamicss theoretical account ( a ) and Pseudo-second dynamicss theoretical account ( B ) of RBBR and RB5 on alive and dead fungous biomass

Table 4 Theoretically determined invariables and experimental values of kinetic theoretical account for surface assimilation of RBBR and RB5 by alive and dead fungous biomass

Biosorbent

Exp.

Theoretical values

First-order kinetic theoretical account

Second-order kinetic theoretical account

qeq

( mg g-1 )

qeq

( mg g-1 )

k1, ad

( min-1 )

r2

qeq

( mg g-1 )

K2, ad

( mg g-1min-1 )

r2

Alive biomass

RBBR

RB5

4.79

4.88

1.48

3.48

0.037

0.039

0.951

0.971

4.93

5.08

0.027

0.019

0.999

0.999

Dead biomass

RBBR

RB5

4.89

4.97

0.26

0.29

0.025

0.039

0.940

0.926

4.95

5.05

0.056

0.059

1.000

0.999

From Table 4, the pseudo-second order kinetic theoretical account provided better correlativity of all experimental informations than the pseudo-first order kinetic theoretical account. In add-on, all the qeq calculated utilizing the second-order kinetic theoretical account were closer to the experimental values than utilizing the first-order kinetic theoretical account.

4. Discussion and Decision

The present survey shows that the biomass of Lentinus strigosus was an effectual biosorbent for the surface assimilation of RBBR and RB5 from aqueous solution. The consequence of contact clip on man-made dyes biosorption capacities of alive and dead fungous biomass. It was found that the dye surface assimilation experiments at the same clip, the dead biomass adsorbed RBBR and RB5 than alive biomass. Accoding to Gallagher et Al. ( 1997 ) and Fu and Viraraghavan ( 2002 ) reported the biosorption of Reactive Red 158 and Congo Red by Aspergillus Niger. It was found that the dye sorption by dead biomass was better than that by alive biomass. The readying of fungous biosorbent by an autoclave procedure increased the sorption capacity of the fungous biomass by interrupting the fungous construction. Harmonizing to Arthur et Al. ( 2007 ) reported the Tametes versicolor reveals the porousness and surface texture. The hempen nature of the wall constituents was found merely in the alive biomass. Dead biomass is likely to be caked by autoclave intervention, connoting that the physical strength of hypae of the fungus was weak. Therefore, the autoclave procedure may besides ease a cementing consequence of fungus wall componants, therefore altering hempen hypae to from the caked morphology of the wall surface. This consequence might do an addition in surface country and porousness of the fungus biomass, and therefore latent sites, accordingly increasing the dye surface assimilation.

The efficiency of surface assimilation isotherms and dynamicss theoretical account has been developed and fitted for the sorption of synthetics dyes onto biomass of White putrefaction fungus, Lentinus strigosus. The consequences show that the sorption of synthetics dyes onto biomass can be described by a Langmuir isotherm and pseudo-second-order-model. The dyes surface assimilation are consistent with strong monolayer sorption and the premise that the rate-limiting measure may be chemical sorption affecting valency forces though exchange or sharing of negatrons between the white putrefaction fungous biomass and dyes molecule. ( Iqbal and Saeed, 2007 ; Ong et al. , 2010 ) .

5. Suggestion

The survey showed that the biomass of Lentinus strigosus reduced man-made dyes efficaciously, but that will be used for existent industrial graduated table should analyze the state of affairs existent effluent from the production procedure to acquire the conditions removed dyes have a suited and effectual for a maximal dye soaking up.

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