Stockholm tar

The pyrolysis or carbonization of hardwoods, eg, beech, birch, or ash, in the manufacture of charcoal yields, in addition to gaseous and lighter Hquid products, a by-product tar in ca 10 wt % yield. Dry distillation of softwoods, eg, pine species, for the production of the so-called DD (destmctively distilled) turpentine yields pine tar as a by-product in about the same amount. Pine tar, also called Stockholm tar or Archangel tar, was at one time imported from the Baltic by European maritime countries for the treatment of cordage and ship hulls it was an important article of commerce from the seventeenth to the nineteenth century. The small amount produced in the late twentieth century is burned as a cmde fuel. Charcoal production from hardwoods, on the other hand, has increased in the 1990s years. 

Penman Cemant. Pettman Cement (PC) is described briefly in Vol 2, C126-R. This water-repellant cement originally consisted of methylated spirit, Stockholm tar, Venetian red, and shellac. It was used as an adhesive in making flares and signals and is mentioned in an early BritP(Refl)... 

A Soap for Washing Bogs and other animals is sometimes made by mixing Stockholm tar (woodtar) with melted soap. The tar should first be dissolved in pyroxylic spirit (wood napbtba). -... 

Stockholm tar, derived from pine by pyrolysis, was fractionated by TLC, and the sample and fractions were examined by MALDI-MS using sinapinic acid and a-cyano as matrices [29]. For the unfractionated tar, the maximum ion intensity was close to m/z 2000 with a high-mass tail to m/z 20,000. Mass spectra of fractions gave ion intensity maxima from m/z 1000 to 7000 as mobility on the TLC plate decreased. 

The efficient removal of tar still remains the main technical barrier for the successful commercialisation of biomass gasification technologies and unless this barrier will be properly addressed biomass gasification applications for power, with the exception of pressurised IGCC, will never materialise. There arc several groups which have been working extensively on tar, however the most prominent teams arc those (in alphabetical order) of the University of Madrid (30, 31), The Royal Institute of Technology in Stockholm (32, 33) and VTT (34, 35). 

Bragc, C. Yu, Q., Chen, G., SjostrOm, K. Use of Amino phase Adsorbent for Biomass Tar Sampling and Separation , Department of Chemical Engineering and Technology, Chemical Technology, Royal Institute of Technology. Stockholm, Sweden. Fuel. Vol. 76, No. 2, pp. 137-142, Jan. 1997... 

Pine tar, Stockholm n. Kiln-burned pine tar produced in Scandinavian countries from wood of the Northern European pine, Pinus sylvestris. 

Stockholm, or wood, tar as well as coal tar and bitumen, pitch or asphalt could be used alone or in admixture with other ingredients and fillers to give a range of sealants exhibiting differing physical properties. 

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