PicolineF raction of Coal-tar Bases (II).

Coal tars and coal tar pitches.

Numerous studies, mostly case reports, have found that occupational exposure to coal tars or coal-tar pitches (coal-tar distillates) is associated with skin cancer, including scrotal cancer; workers in these studies have included patent-fuel (coal-briquette) workers, pitch loaders, workers in electrical trades, and optical-lens polishers (IARC 1985, 1987). A 1946 study in the United Kingdom fou...

Cold Applied Coal Tar Paints

Coal Tar Analysis by Lc/ms

The production of liquids from coal gives rise to complex intermediates which require detailed analysis to understand the processes occurring and to make effective use of the products. Analysis has hitherto been based on structural parameters from NMR methods (1) to give the average characteristics of the sample, supplemented by molecular information from GC and GC/MS. The gas chromatographic a...

Occupational Exposures during Coal-tar Distillation

Coal tar is obtained by cooling the gas that is formed during the destructive distillation of coal to approximately ambient temperature. It is a black, viscous liquid composed primarily of a complex mixture of condensed-ring aromatic hydrocarbons. It may contain phenolic compounds, aromatic nitrogen bases and their alkyl derivatives, and paraffinic and olefinic hydrocarbons. Coal-tar pitch is t...

Chemical Structure Changes of Coal, Char, and Tar during Devolatilization

Enormous progress has been made in coal pyrolysis research during the last decade. Models of coal devolatilization have progressed from simple rate expressions based on total mass release's to empirical relationships based on the elemental composition of the parent coal3 to models that attempt to describe the macromolecular network of the ~ o a l . ~ ~ Measurements of particle temperature durin...