Dodecylbenzenesulphonic acid

Endpoint summary

Additional information

Physical and chemical properties

 

Dodecylbenzenesulphonic acid /Dodecylbenzenesulfonic acid/Benzenesulfonic acid, dodecyl-

1.Appearance

Dodecylbenzenesulfonic acid (DBS) is a liquid organic substance (light yellow to brown) with characteristic odor at 20°C and 1013 hPa. 

 

2.Melting point

Dodecylbenzenesulphonic acid has a melting point of 10 deg C

Using the EPI Suite Mpbwin (v.1.43) QSAR model, a Melting Point of 177.76 deg C (Weighted Value) was established.

 

3.Boiling point

Using the EPI Suite Mpbwin (v.1.43) QSAR model, a Boiling Point of 459.93 deg C (estimated) was established.

Boiling Point of 205 deg C at 1013 hPa was established according IUCLID cited source.

 

4.Specific gravity

1.06

 

5.Vapour pressure

A QSAR method predicts the vapour pressure of this substance to be 1.06E-008 Pa at 25C.

6.Water solubility

100mg/l

9.1359 mg/l

0.7032 mg/l

The substance is moderately soluble (100 mg/l) in water. Water solubility of 100 mg/l for sodium dodecylbenzenesulfonate as a surrogate for benzene sulfonic acid, dodecyl- (27176-87-0) was determinated. Sodium dodecylbenzenesulfonate (CAS No.25155-30-0, EC Number; 246-680-4) is a very close analogue of the dissociated acid because it readily dissociates in water and release the dodecylbenzene sulfonic anion in solution.

Substance is predicted by QSAR method (EPI Suite v 4.1/WATERNTv 1.01) to be slightly soluble( 9.1359 mg/l) with water

Substance is predicted by QSAR method (EPI Suite v 4.1/WSKOW v1.42 ) to be slightly soluble ( 0.7032 mg/l) with water.

 

7.Partition co-efficient

A reliable QSAR method predicts a value for the partition co-efficient (logKow) of 4.78 for this substance.

8.Hydrolysis as a function of pH

The hydrolysis of the substance was less than 10% over the 5 days.Based on these results, dodecylbenzenesulfonic acid was hydrolytically stable (half life > 1 year) specified by the OECD Guidelines .

 9.Adsorption/desorption

The log of the adsorption coefficient (KOC) of LAS-C12 was estimated to be log KOC = 3.21 which is equal to a KOC value of 2360 . Sodium dodecylbenzenesulfonate (CAS No. 25155-30-0) is a very close analogue of the dissociated acid because it readily dissociates in water and release the dodecylbenzene sulfonic anion in solution.

The log of the adsorption coefficient (KOC) of Dodecylbenzenesulphonic acid was estimated to be log KOC =3.5691which is equal to a KOC value of 3707 using the KOCWIN v2.00 QSAR method.

10.Dissociation constant

A dissociation constant value of 0.7 was obtained using an accepted calculation method. The result is considered to be reliable

 

11.Flammability

From the compositional description and the structural formula given, it can be concluded that this substanceDodecylbenzenesulphonic acid CAS 27176-87-0, (EINECS) 248-289-4 is not pyrophoric (will not ignite or emit flammable gases on contact with air, damp air, or water) nor does it exhibit the property of flammability (will not easily burn when ignited or contribute to the combustion of other materials). There are no functional groups or other structural alerts present that would support any concern that this substance should be classified as dangerous according to the criteria for evaluating flammability, which is furthermore confirmed by long term handling experience.

12.  Flash point

 Flash point of Dodecylbenzenesulphonic acid is 149°C ( 300°F) at atmospheric pressure.

 

13.Explosiveness

 

From the compositional description and the structural formula given, it can be concluded that the substance Dodecylbenzenesulphonic acid CAS 27176-87-0, (EINECS) 248-289-4 does not exhibit explosive properties (will not detonate or deflagrate, under conditions of excessive heating with or without confinement, impact, or friction to produce heat and or gas). There are no functional groups or other structural alerts associated with explosive properties or tendencies that would indicate that this substance will manifest explosive properties. Similarly, the calculated Oxygen Balance is less than -200 suggesting that testing need not be conducted and that a negative result can be predicted. Thus, this substance should not be classified as dangerous according to the criteria for explosivity, which is furthermore confirmed by long term handling experience.

14.Stability In Organic Solvent

From the compositional description and the structural formula given, it can be concluded that the substance Dodecylbenzenesulphonic acid CAS 27176-87-0, (EINECS) 248-289-4 is stable in organic solvents. There are no functional groups or other structural alerts present that would indicate that this substance should be reactive or give rise to any instability under routine storage conditions or testing conditions in general. This reality is furthermore confirmed by long term handling experience in addition to observations made during subsequent downstream formulating and blending operations where this substance is also observed to be very stable.

It should be noted that this substance is not completely soluble in some very polar low molecular weight organic solvents (egs. alcohols, esters, ketones, and ethers). However, this is not the result of substance instability, and no reactions between these solvents and the functional groups present in this substance would be expected.

15.Viscosity

960 mPa · s .

 

16.Decomposition products

Decomposesand produces toxic fumes including sulfur oxides and hydrogen sulfide. Reacts with bases and oxidants. This produces sulfur oxides. This generates toxic hazard. Attacks metals. 

 

17.Autoignition temperature

From the compositional description, the structural formula given, it can be concluded that it is not necessary to evaluate the ignition temperature of this substance by either the Self- or Auto-Ignition testing criteria indicated in the TGD.

There are no functional groups or other structural alerts present that indicate that this substance would spontaneously ignite in air when exposed to a hot surface and thus should not be classified as dangerous with respect to this endpoint.

This empirical evaluation is furthermore confirmed by long term handling experience. The study is therefore considered scientifically unjustified.

Therefore testing for Auto flammability does not need to be performed.

 

18.Reactivity

Reacts with bases and oxidants. This produces sulfur oxides. This generates toxic hazard. Attacks metals. 

  

19.Composition of commercial product

Commercial LAS consists of more than 20 individual components.Dodecylbenzenesulfonic acid is one of the linear alkylbenzene sulfonic acids(LAS). The alkyl carbon chain typically has 10 to 14 carbon atoms and the linearity of the alkyl chains ranges from 87 to 98%. While commercial LAS consists of more than 20 individual components, the ratio of the various homologs and isomers, representing different alkyl chain lengths and aromatic ring positions along the linear alkyl chain, is relatively constant in currently produced products, with the weighted average carbon number of the alkyl chain based on production volume per region between 11.7-11.8. Dodecylbenzenesulfonic acid is regarded with 12C-LAS therefore some endpoints were assessed by 12C-LAS.

20.Oxidizing properties

From the compositional description and the structural formula given, it can be concluded that the substance Dodecylbenzenesulphonic acid CAS 27176-87-0, (EINECS) 248-289-4 does not exhibit oxidizing properties (will not cause or contribute to the combustion of other materials by virtue of its own inherent oxidation or reduction potential). There are no functional groups or other structural alerts present that would indicate that this substance would promote oxidation and thus should not be classified as dangerous according to the criteria for evaluating oxidizing properties. Furthermore, this is confirmed by long term handling experience.

 Table    Summary of physico-chemical properties

Property	Value	References
Physical state	Liquid	HSDB, 2002
Substance type	Organic	HSDB, 2002
Color	Light yellow to brown	HSDB, 2002
Molecular Weight	326.54 g/mol	HSDB, 2002
Melting point	177.76°C (calculated) 10°C	US EPA, 2011 Verschueren, 1996
Boiling point	459.93°C (calculated) 205°C	US EPA, 2011 IUCLID cite
Vapour pressure	1.06E-008 Pa at 25C.	US EPA, 2011
Water solubility	100 mg/L at 25°C (experimental for sodium dodecylbenzenesulfonate) 9.1359 mg/l (calculated) 800 mg/L at 25°C (experimental for sodium dodecylbenzenesulfonate)	Smith, D.L.,1997   US EPA, 2011 Geyer et al., 1981
Dissociation constant (pKa)	0.7 (estimated)	ACD, 2009
Partition coefficient n-octanol/water (log value)	log Kow=4.78 (calculated) log Kow=1.96 (experimental for sodium dodecylbenzenesulfonate)	US EPA, 2011   Hand and Williams, 1987
Half-life in air	0.654 days = 7.85 hours	US EPA, 2011
Henry Law Constant	6.27E-008 atm-m3/mole (6.35E-003 Pa-m3/mole)	US EPA, 2011

Sodium dodecylbenzenesulfonate (CAS No. 25155-30-0) is a very close analogue of the dissociated acid because it readily dissociates in water and release the dodecylbenzene sulfonic anion in solution.