44 SECTIONAL ADDRESSES. 



new type of resins to which the name resinolic acids has been given, as 

 they are intermediate in chemical properties between resinols and resinoic 

 acids. Resinolic acids in the presence of ammonia are largely responsible 

 for the dark red colour of the aqueous effluents from gasworks. These 

 aqueous liquors have also furnished on systematic extraction aniline, 

 pyridine and a-picoline, and the series of fatty acids ranging from formic 

 to TC-valeric acids. 



High Pressure Chemistry. 



During the past ten years increasing attention has been directed to 

 the use of pressure as a means of facilitating the course of chemical 

 reactions, and research on high pressure syntheses was started at the 

 laboratory in 1926 on the recommendation of the Chemistry Co-ordinating 

 Research Board, whose members were impressed by the possibilities 

 revealed by the work of Patart in France and of the Badische Anilin und 

 Soda Fabrik in Germany. 



The plant required for this investigation was designed and built in 

 the laboratory workshop, and the earliest experiments were carried out 

 with hand compressors. Subsequently, motor-driven compressors and 

 circulators were added to the equipment. This plant was first tried out 

 with catalysts of the Patart type (normal or basic zinc chromate) in order 

 to gain skill and confidence in the process. It was thus found that on 

 passing the mixed gases (1 vol. CO, 2 vols. H.^) at the rate of 30,000 vols, 

 per hour, measured at N.T.P. over unit volume of such a catalyst at 380° 

 and under 200 atmospheres' pressure the hourly production of methyl 

 alcohol was about twice the volume of catalyst space. 



The addition of cobalt chromate or nitrate to the foregoing zinc 

 chromate catalyst led to an interesting development, since with the more 

 complex catalyst ethyl alcohol and other higher' alcohols made their 

 appearance, although methyl alcohol remained the predominant product. 

 Small amounts of aldehydes and acids were also detected. By the use of 

 mixed cobalt catalysts containing zinc, together with chromium or 

 manganese, the following alcohols have been obtained in addition to 

 methyl and ethyl alcohols : ?i-propyl, «-butyl, tso-butyl and n-amyl 

 alcohols and racemoid 1-methyl-propylcarbinol CH,.CH^.CH(CH.,).CHo.OH. 

 So far only primary alcohols have been detected. Aldehydic products have 

 been identified as follows : formaldehyde, acetaldehyde, propaldehyde, 

 w-butaldehyde and also certain aldehydals arising from the condensation 

 of the foregoing aldehydes and alcohols. Moreover, the synthetic products 

 contain formic, acetic, propionic and M-butyric acids. 



The addition of even small proportions of cobalt to copper-manganese 

 oxide catalysts (Audibert type) has a marked effect on the production of, 

 ethyl alcohol and its homologues, and a similar result is noticed on] 

 replacing the cobalt in these catalysts by iron. Traces of alkali hydroxide! 

 promote the formation of higher alcohols, and in this respect potash is' 

 more efficacious than lithia. 



Helium from Monazite Sand. 

 In addition to their synthetic experiments, the staff engaged on high 

 pressure chemistry have brought to completion a research on the extrac- 

 tion of helium from the monazite sand conveyed to this country from 



