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THE ALUMNI JOURNAL, 



lime is transported in a continuous stream 

 by single or double conveyors in an 

 opposite direction to the current of dilute 

 chlorine aud the bleaching powder form- 

 ed delivered direct into casks. 



ADVANTAGES OF THE DEACON PROCESS. 



Mr. Deacon's beautiful and scientific 

 process thus involves still more movement 

 of materials than the very simple process 

 of Mr. Weldon, because in lieu of large 

 volumes ot liquids he only moves a cur- 

 rent of gas through his apparatus, which 

 requires a minimum of energy. The only 

 raw material used for converting hydro- 

 chloric acid into chlorine is atmospheric 

 air, the cheapest of all at our command. 

 The hydrochloric acid which has not been 

 converted into chlorine by the process is 

 all obtained, dissolved in water, as muri- 

 atic acid, and is not lost, as in previous 

 processes, but is still available to be con- 

 verted into chlorine by other methods, 

 or to be used for other purposes. 



In spite of these distinct advantages, 

 this process took a long time before it 

 became adopted as widely as it undoubt- 

 edly deserved. This was mainly due to 

 the fact that the economy in the use of 

 muriatic acid which it eflfected was at the 

 time when the process was brought out, 

 and for many years afterwards, no object 

 to the majority of chlorine manufacturers, 

 who were still producing more of this 

 commodity than they could use. More- 

 over, there were other reasons. The 

 plant required for this process, although 

 so simple in principle, is very bulky in 

 proportion to the quantity of chlorine 

 produced, and as I have pointed out, the 

 process only succeeded in converting about 

 one-third of the hydrochloric acid pro- 

 duced into chlorine, the remainder being 

 obtained as muriatic acid, which had in 

 most instances to be converted into chlo- 

 rine by the Weldon process: so that the 

 Deacon process did not constitute an en- 



tirely self-contained method for this 

 manufacture. This defect, of small mo- 

 ment as long as muriatic acid was pro- 

 duced in excessive quantities, was only 

 remedied by an invention of Mr. Robert 

 Hasenclever a short number of years ago 

 when by the rapid development of the am- 

 monia soda process the previous existing 

 state of things had been completely 

 changed, and when, at least on the Con- 

 tinent, muriatic acid was no longer an 

 abundant and valueless bye-product, but 

 on the contrary, the alkali produced by 

 the Le Blanc process had become a bye- 

 product of the manufacture of chlorine, 

 Mr. Hasenclever, in order to make the 

 whole of the muriatic acid he produces 

 available for conversion into chlorine by 

 the Deacon process, introduces the liq- 

 uid muriatic acid in a continuous stream 

 into hot sulphuric acid contained in a 

 series of stone vessels, through which he 

 passes a current of air. He thus obtains 

 a mixture of hydrochloric acid and air, 

 well adapted for the Deacon process, the 

 water of the muriatic acid remaining with 

 the sulphuric acid, from which it is sub- 

 sequently eliminated by evaporation. In 

 this way the chlorine in the hydrochloric 

 acid can be almost entirely obtained in 

 its free state by the simplest imaginable 

 means, and with the intervention of no 

 other chemical agent than atmospheric 

 air. Since their introduction the Deacon 

 process has supplanted the Welden pro- 

 cess in nearly all the largest chlorine 

 works in France and Germany, and is 

 now also making very rapid progress in 

 this country. 



THE WELDON-PECHINEY PROCESS. 



Mr. Weldon, when he decided to give 

 up his manganite of magnesia process, 

 by no means relaxed his efforts to work 

 out a chlorine process which should util- 

 ize the whole ot the muriatic acid. While 

 working with manganite of magnesia 



