William Henry Perkin

Sir William Henry Perkin, FRS (12 March 1838 – 14 July 1907) was an English chemist best known for his discovery, at the age of 18, of the first aniline dye, mauveine.

Early years

William Perkin was born in the East End of London, the youngest of seven children. His father was a successful carpenter. His mother, Sarah, was of Scottish descent but moved to east London as a child.[1] He was baptised in the parish church of St Paul's, Shadwell, which had been connected to such luminaries as James Cook, Jane Randolph Jefferson (mother of Thomas Jefferson) and John Wesley.

Perkin attended the City of London School, where he was taught by Thomas Hall, who fostered his scientific talent and encouraged him to pursue a career in chemistry.[1]
Discovery of mauveine

In 1853, at the precocious age of 15, Perkin entered the Royal College of Chemistry in London (now part of Imperial College London), where he began his studies under August Wilhelm von Hofmann.[2] At this time, chemistry was still in a quite primitive state: although the atomic theory was accepted, the major elements had been discovered, and techniques to analyze the proportions of the elements in many compounds were in place, it was still a difficult proposition to determine the arrangement of the elements in compounds. Hofmann had published a hypothesis on how it might be possible to synthesize quinine, an expensive natural substance much in demand for the treatment of malaria.[1] Perkin, who had by then become one of Hofmann's assistants, embarked on a series of experiments to try to achieve this end. During the Easter vacation in 1856, while Hofmann was visiting his native Germany, Perkin performed some further experiments in the crude laboratory in his apartment on the top floor of his home in Cable Street in east London. It was here that he made his great discovery: that aniline could be partly transformed into a crude mixture which when extracted with alcohol produced a substance with an intense purple color.[2] Perkin, who had an interest in painting and photography, immediately became enthusiastic about this result and carried out further trials with his friend Arthur Church and his brother Thomas. Since these experiments were not part of the work on quinine which had been assigned to Perkin, the trio carried them out in a hut in Perkin's garden, so as to keep them secret from Hofmann.

They satisfied themselves that they might be able to scale up production of the purple substance and commercialize it as a dye, which they called mauveine. Their initial experiments indicated that it dyed silk in a way which was stable when washed or exposed to light. They sent some samples to a dye works in Perth, Scotland, and received a very promising reply from the general manager of the company, Robert Pullar. Perkin filed for a patent in August 1856, when he was still only 18.[2] At the time, all dyes used for colouring cloth were natural substances, many of which were expensive and labour-intensive to extract. Furthermore, many lacked stability, or fastness. The colour purple, which had been a mark of aristocracy and prestige since ancient times, was especially expensive and difficult to produce—the dye used, known as Tyrian purple, was made from the glandular mucus of certain molluscs. Its extraction was variable and complicated, and so Perkin and his brother realised that they had discovered a possible substitute whose production could be commercially successful.[1]

Perkin could not have chosen a better time or place for his discovery: England was the cradle of the Industrial Revolution, largely driven by advances in the production of textiles; the science of chemistry had advanced to the point where it could have a major impact on industrial processes; and coal tar, the major source of his raw material, was an abundant by-product of the process for making coal gas and coke.[3]

Having invented the dye, Perkin was still faced with the problems of raising the capital for producing it, manufacturing it cheaply, adapting it for use in dyeing cotton, gaining acceptance for it among commercial dyers, and creating public demand for it. However, he was active in all of these areas: he persuaded his father to put up the capital, and his brothers to partner him in the creation of a factory; he invented a mordant for cotton; he gave technical advice to the dyeing industry; and he publicized his invention of the dye. Public demand was increased when a similar colour was adopted by Queen Victoria in England and by Empress Eugénie, wife of Napoleon III, in France, and when the crinoline or hooped-skirt, whose manufacture used a large quantity of cloth, became fashionable. Everything seemed to fall into place by dint of hard work, with a little luck, too. Perkin became rich.[1]

After the discovery of mauveine, many new aniline dyes appeared (some discovered by Perkin himself), and factories producing them were constructed across Europe.
Later years

William Perkin continued active research in organic chemistry for the rest of his life: he discovered and marketed other synthetic dyes, including Britannia Violet and Perkin's Green; he discovered ways to make coumarin, one of the first synthetic perfume raw materials, and cinnamic acid. (The reaction used to make the latter became known as the Perkin reaction.)[4] Local lore has it that the colour of the nearby Grand Union Canal changed from week to week depending on the activity at Perkin's Greenford dyeworks. In 1869, Perkin found a method for the commercial production from anthracene of the brilliant red dye alizarin, which had been isolated and identified from madder root some forty years earlier in 1826 by the French chemist Pierre Robiquet, simultaneously with purpurin, another red dye of lesser industrial interest, but the German chemical company BASF patented the same process one day before he did.[2] Over the next few years, Perkin found his research and development efforts increasingly eclipsed by the German chemical industry, and so in 1874 he sold his factory and retired from business, a very wealthy man.

Perkin received many honours in his lifetime. In 1879, he received the Royal Society's Royal Medal, and then, in 1889, its Davy Medal. He was knighted in 1906, and in the same year he was awarded the first Perkin Medal, established to commemorate the fiftieth anniversary of his discovery of mauveine.[2] Today the Perkin Medal is widely acknowledged as the highest honour in American industrial chemistry and has been awarded annually by the American section of the Society of Chemical Industry to many inspiring and gifted chemists.

Perkin died in 1907 of pneumonia and appendicitis.

Today blue plaques mark the sites of Perkin's home in Cable Street, by the junction with King David Lane, and the Perkin factory in Greenford.

References

1. ^ a b c d e UXL Encyclopedia of World Biography (2003).[1] Accessed 18 March 2008.
2. ^ a b c d e Encyclopedia Britannica, 1911 edition.[2] Accessed 18 March 2008.
3. ^ Michigan State University, Department of Chemistry website.[3] Accessed 18 March 2008.
4. ^ Michigan State University, Department of Chemistry website.[4] Accessed 18 March 2008.