Encyclopedia of Environmental Science and Engineering, Volume I and II

PCBs AND ASSOCIATED AROMATICS 865

COMMERCIAL APPLICATIONS OF PCBs

Because of their physical properties, PCBs found extensive

applications in electrical equipment such as power trans-

formers and capacitors, as well as in hydraulic machinery,

vacuum pumps, compressors and heat-exchanger fluids.

Other uses include:

• lubricants


• fluorescent light ballasts


• paints


• glues


• waxes


• carbonless copy paper


• inks, including newspapers


• dust-control agents for dirt road
  
  
  • solvents for spreading insecticides
  
  
  • cutting oils.
  
  
  
  

Table 9 illustrates the diversity of applications in the

United States of different Aroclors.

A numbering system used in Aroclor products describes,

firstly the number of carbon atoms in the molecule by the first

two digits (12) and, secondly, the last two digits indicate the

percentage of chlorine in the product. For example, Aroclor

1254 is biphenyl with 6 carbon atoms in each of two phenyl

rings and 54% chlorine by weight.

Aroclor 1016 is an exception to the rule. It was not manu-

factured with 16% chlorine but rather is the name given to

a product obtained by distilling Aroclor 1242. The distillate

product contained 41% chlorine and the percentage of the rel-

atively low boiling, low chlorine isomers, with 3 or 4 chlorine

TABLE 7

Some of the environmentally important properties of PCB homologous series

PCB Homologous Series Molecular Weight

(g/mol)

Water Solubilityat

25°C (g/m^3 )

Log Kow Bioconcentration

Factor in Fish

Evaporation Rateat

25°C (g/(m^2 h))

Biphenyl 154.2 9.3 4.3 1000 0.92

Monochlorobiphenyl 188.7 4.0 4.7^2500 0.25

Dichlorobiphenyl 223.1 1.6 5.1^6300 0.065

Trichlorobiphenyl 257.5 0.65 5.5 1.6 ^104 0.017

Tetrachlorobiphenyl 292.0 0.26 5.9 4.0 ^104 4.2 ^10 ^3

Pentachlorobiphenyl 326.4 0.099 6.3 1.0 ^105 1.0 ^10 ^3

Hexachlorobiphenyl 360.9 0.038 6.7 2.5 ^105 2.5 ^10 ^4

Heptachlorobiphenyl 395.3 0.014 7.1 6.3 ^105 6.2 ^10 ^5

Octachlorobiphenyl 429.8 5.5 ^10 -3 7.5 1.6 ^106 1.5 ^10 ^5

Nonachlorobiphenyl 464.2 2.0 ^10 -3 7.9 4.0 ^106 3.5 ^10 ^6

Decachlorobiphenyl 498.7 7.6  10 -4 8.3 1.0  107 8.5  10 ^7

TABLE 8

Some Aroclor properties of environmental importance

Aroclor

Property 1016 1242 1248 1254 1260

Vapor Pressure at 25°C (Pa) 0.10 0.091 0.023 6.7  10 ^3 6.4  10 ^4

Viscosity at 25°C (mPa.s) 45 69 280 2.0  103 1.9  105

Specific gravity at 25°C 1.4 1.4 1.4 1.5 1.6

Fluid density at 25°C 1,370 1,381 1,445 1,539 1,621

Solubility in water at 25°C (g/

m3)

0.84 0.75 0.32 0.14 0.035

Log 10 Kow 4.4–5.8 4.5–5.8 5.8–6.3 6.1–6.8 6.3–7.5

Bioconcentration 1.3  103  3.2  104 1.6  103  3.2  104 3.2  104  1.0  105 6.3  104  3.2  105 1.0  105  1.6  106

Factor in Fish —————

Evaporation rate at 25°C

(g/(m2h)) 0.031 0.029 8.3  10-3 2.7  10-3 2.9  10-4

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