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Environmental fate & pathways

Phototransformation in air

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Description of key information

Using the AOPWIN QSAR model, the photochemical degradation rate of Sodium isobutyl xanthate in the atmosphere is 16.0392 E-12 cm3/molecule-sec, with a resultant predicted half live of 8.002 Hrs (0.667 Days (12-hr day; 1.5E6 OH/cm3).
If released to air, a vapor pressure of 1.26E-009 mm Hg at 25 deg C (1.26E-009 mm Hg is equivalent to 1.68E-007 Pa ) indicates Sodium isobutyl xanthate will exist solely as a vapor in the atmosphere. Vapor-phase Sodium isobutyl xanthate will be degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals; the half-life for this reaction in air is estimated to be 0.667 days, calculated from its rate constant of 16.0392 E-12 cm3/molecule-sec at 25 deg.
Xanthates do not contain chromophores that absorb at wavelengths >290 nm and therefore Sodium isobutyl xanthate is not expected to be susceptible to direct photolysis by sunlight.

Key value for chemical safety assessment

Half-life in air:
0.667 d
Degradation rate constant with OH radicals:
0 cm³ molecule-1 s-1

Additional information

If released to air, a vapor pressure of 1.26E-009 mm Hg at 25 deg C (1.26E-009 mm Hg is equivalent to 1.68E-007 Pa ) indicates Sodium isobutyl xanthate will exist solely as a vapor in the atmosphere. Vapor-phase Sodium isobutyl xanthate will be degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals; the half-life for this reaction in air is estimated to be 0.667 days, calculated from its rate constant of 16.0392 E-12 cm3/molecule-sec at 25 deg. Xanthates do not contain chromophores that absorb at wavelengths >290 nm and therefore Sodium isobutyl xanthate is not expected to be susceptible to direct photolysis by sunlight.

Using the AOPWIN QSAR model, the photochemical degradation rate of Sodium isobutyl xanthate in the atmosphere is 16.0392 E-12 cm3/molecule-sec, with a resultant predicted half live of 8.002 Hrs (0.667 Days (12-hr day; 1.5E6 OH/cm3)

OVERALL OH Rate Constant = 16.0392 E-12 cm3/molecule-sec

HALF-LIFE = 0.667 Days (12-hr day; 1.5E6 OH/cm3)

HALF-LIFE = 8.002 Hrs

If released to air, a vapor pressure of1.26E-009 mm Hg at 25 deg C (1.26E-009 mm Hg is equivalent to 1.68E-007 Pa ) indicates Sodium isobutyl xanthate will exist solely as a vapor in the atmosphere. Vapor-phase Sodium isobutyl xanthate will be degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals; the half-life for this reaction in air is estimated to be0.667days, calculated from its rate constant of16.0392 E-12 cm3/molecule-secat 25 deg.

 

Xanthatesdo not contain chromophores that absorb at wavelengths >290 nm and therefore Sodium isobutyl xanthate is not expected to be susceptible to direct photolysis by sunlight.