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Reference
Endpoint:
adsorption / desorption: screening
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: data is from peer reviewed journal
Justification for type of information:
data is from peer reviewed journal
Qualifier:
according to
Guideline:
other: refer principle below
Principles of method if other than guideline:
To determine adsorption percentage on test chemical -[3-(1,3-dihydro-1,3,3-trimethyl-2H-indol-2-ylidene)prop-1-enyl]-1,3,3-trimethyl-3H-indolium chloride on sewage sludge.
GLP compliance:
not specified
Type of method:
batch equilibrium method
Media:
sewage sludge
Radiolabelling:
not specified
Test temperature:
303 K
Analytical monitoring:
not specified
Details on sampling:
Samples were withdrawn at regular interval
Details on matrix:
Details on Matrix:
Sewage sludge was used as matrix (biosorbent) obtained from sewage treatment plant, Pholriwal, Jalandhar (India).

Pretreatment of matrix:
20.0 g of dry sludge was treated with 100 mL of 1 M H2SO4. This pretreatment helped in removing excess of urea and hydrogen sulphide gas.
The sludge was allowed to stand in acid overnight. This was then separated by filtration. The residue was washed with deionized water several times till the washing attained neutral pH. The water was drained off and sludge was dried in hot air oven at 80°C for 24 h. The dried material was ground to a fine powder in an electrical grinder. This was then passed through a mesh screen to get particles < 500 μm size. This was then stored in air tight container for further use.
Details on test conditions:
Details on test conditions
- pH: study was done at different pH

TEST SYSTEM: The experiments were conducted by taking 50 mL of dye solution in Erlenmeyer flask and adding required amount of biosorbent in that. The pH of different solutions was adjusted with 0.1 N HCl and 0.1 N NaOH using microprocessor based pH meter by Toshniwal India. The biosorbent dose was varied from 2.5 g/L to 20.0 g/L. The solutions were kept in incubator shaker at 303 K.
Sample No.:
#1
Duration:
2 h
Initial conc. measured:
250 other: mg/L
pH:
6
Temp.:
303 K
Remarks:
other details not available
Sample No.:
#1
Type:
other: % adsorped
Value:
92.5 other: percentage
pH:
6
Temp.:
303 K
Matrix:
sewage sludge
Remarks on result:
other: other details not available
Transformation products:
not specified

Temperature (K)

KF

n

Qo(mg/g)

b(L/mg)×10-2

303

3.6837

1.5582

72.48

2.7156

 

313

3.5906

1.1565

138.72

1.1199

323

1.0712

0.9335

295.85

0.9761

WhereQ0(mg/g) andb(L/mg) are Langmuir constants related to maximum adsorption capacity and equilibrium constant related to binding energy respectively, while KF and n are Freundlich constants related to adsorption capacity and sorption intensity

Validity criteria fulfilled:
not specified
Conclusions:
The test chemical 2-[3-(1,3-dihydro-1,3,3-trimethyl-2H-indol-2-ylidene)prop-1-enyl]-1,3,3-trimethyl-3H-indolium chloride (CAS no. 6320-14-5) showed 92.2 % adsorption on pretreated sewage sludge in 2 hrs. On the basis of percentage adsorption value it can be concluded that test chemical is expected to show very strong sorption to soil and sediment.
Executive summary:

Adsorption experiment was carried to determine percentage adsorption of test chemical 2-[3-(1,3-dihydro-1,3,3-trimethyl-2H-indol-2-ylidene)prop-1-enyl]-1,3,3-trimethyl-3H-indolium chloride (CAS no. 6320-14-5) on sewage sludge. Sewage sludge was used as matrix (biosorbent) obtained from sewage treatment plant, Pholriwal, Jalandhar (India). Matrix was pretreated in this treatment 20.0 g of dry sludge was treated with 100 mL of 1 M H2SO4. This pretreatment helped in removing excess of urea and hydrogen sulphide gas.

The sludge was allowed to stand in acid overnight. This was then separated by filtration. The residue was washed with deionized water several times till the washing attained neutral pH. The water was drained off and sludge was dried in hot air oven at 80°C for 24 h. The dried material was ground to a fine powder in an electrical grinder. This was then passed through

a mesh screen to get particles < 500 μm size. This was then stored in air tight container for further use.The experiments were conducted by taking 50 mL of test chemical solution in Erlenmeyer flask and adding required amount of biosorbent in that. The pH of different solutions was adjusted. The biosorbent dose was varied from 2.5 g/L to 20.0 g/L.The solutions were kept in incubator shaker at 303 K.The batch adsorption experiments show that the adsorption of test chemical over sewage sludge is dependent on pH, amount of adsorbent, concentration, contact time, and temperature, and almost 92.5% could be accomplished at low concentrations, whereas at higher concentrations, the adsorption was slightly decreased to 90%. Freundlich and Langmuir parameters for adsorption of test chemical over sewage sludge at different temperatures and their coefficients are also determined which is given in table1. On the basis of percentage adsorption value it can be concluded that test chemical is expected to show very strong sorption to soil and sediment.

Description of key information

The test chemical  2-[3-(1,3-dihydro-1,3,3-trimethyl-2H-indol-2-ylidene)prop-1-enyl]-1,3,3-trimethyl-3H-indolium chloride (CAS no. 6320-14-5) showed 92.2 % adsorption on pretreated sewage sludge in 2 hrs. On the basis of percentage adsorption value it can be concluded that test chemical is expected to show very strong sorption to soil and sediment.

Key value for chemical safety assessment

Additional information

Experimental data and predicted data studies have been reviewed for adsorption endpoint for target chemical  2-[3-(1,3-dihydro-1,3,3-trimethyl-2H-indol-2-ylidene)prop-1-enyl]-1,3,3-trimethyl-3H-indolium chloride (CAS no. 6320-14-5) and their results are summarized below.

 

In an experimental data study the adsorption experiment was carried to determine percentage adsorption of test chemical 2-[3-(1,3-dihydro-1,3,3-trimethyl-2H-indol-2-ylidene)prop-1-enyl]-1,3,3-trimethyl-3H-indolium chloride (CAS no. 6320-14-5) on sewage sludge. Sewage sludge was used as matrix (biosorbent) obtained from sewage treatment plant, Pholriwal, Jalandhar (India). Matrix was pretreated in this treatment 20.0 g of dry sludge was treated with 100 mL of 1 M H2SO4. This pretreatment helped in removing excess of urea and hydrogen sulphide gas.

The sludge was allowed to stand in acid overnight. This was then separated by filtration. The residue was washed with deionized water several times till the washing attained neutral pH. The water was drained off and sludge was dried in hot air oven at 80°C for 24 h. The dried material was ground to a fine powder in an electrical grinder. This was then passed through a mesh screen to get particles < 500 μm size. This was then stored in air tight container for further use. The experiments were conducted by taking 50 mL of test chemical solution in Erlenmeyer flask and adding required amount of biosorbent in that. The pH of different solutions was adjusted. The biosorbent dose was varied from 2.5 g/L to 20.0 g/L. The solutions were kept in incubator shaker at 303 K.The batch adsorption experiments show that the adsorption of test chemical over sewage sludge is dependent on pH, amount of adsorbent, concentration, contact time, and temperature, and almost 92.5% could be accomplished at low concentrations, whereas at higher concentrations, the adsorption was slightly decreased to 90%. Freundlich and Langmuir parameters for adsorption of test chemical over sewage sludge at different temperatures and their coefficients are also determined which is given in table1. On the basis of percentage adsorption value it can be concluded that test chemical is expected to show very strong sorption to soil and sediment.

 

Above experimental study was supported by predicted data in this study the Soil Adsorption Coefficient i.e. Koc value of test chemical 2-[3-(1,3-dihydro-1,3,3-trimethyl-2H-indol-2-ylidene)prop-1-enyl]-1,3,3-trimethyl-3H-indolium chloride (CAS No. 6320-14-5) was estimated using EPI suite KOCWIN Program (v2.00) as 12.5 L/kg (log Koc= ) by means of MCI method at 25 deg. C.  This log Koc value indicates that test chemical 2-[3-(1,3-dihydro-1,3,3-trimethyl-2H-indol-2-ylidene)prop-1-enyl]-1,3,3-trimethyl-3H-indolium chloride has very strong sorption to soil and therefore test chemical has negligible migration potential to ground water.

 

On the basis of both the studies mentioned above it is concluded that test chemical 2-[3-(1,3-dihydro-1,3,3-trimethyl-2H-indol-2-ylidene)prop-1-enyl]-1,3,3-trimethyl-3H-indolium chloride (CAS no. 6320-14-5) is expected to show strong sorption to soil and sediment and therefore has negligible migration potential to ground water.