V O L U M E 2 3 , N O . 6, J U N E 1 9 5 1 volves the removal of coppei ab the sulfide, described previouhl\ 111 tho ensuing study of propohed pioccdules, the values found tn this method were accepted :IS t r w v,ilucls. KEL.4TIVE ECONOMY OF METHODS FOR SICKEL I N A L L ~ I I N U . \ l ALLOY s
.\ride from the obvious evils of hj-drogen sulfide, the nitsthod i n which copper is removed 1)y clcctrol\-sis has the atlvantagc, from the standpoint of the tinir wquircd for a deterniination, of 45 minutes compared \\-ith 55 t o GO minutes required in the sulfide 1nethoti. Thcl method by \vhic~hnicnkcal is rl(~tc~1~mined in 1 he p r e w n c ~of
883
copper is recommended for the routine analysis of aluminum alloys. By this method 31 samples were analyzed in 15 hours. This indicates a saving of time which should be valuable to laboratories where large numbers of nickel detrrminations are required routinely. LITERATURE CITED
Testing Materials, Philitdclphia, Pa., "hIethods of Chemical Analysis of Metals," pp. 160-1, 1946. ( 2 ) Cooper, M.D., ANAL.(;HEM., 23,875 (1951). < Ij
.hi,
SOC.
1931. Presented a t the Fourth Annual Pittahuroii Analytical Symposium. January 1949. KKCLIVED.Ingust 31,
Simple Methylo1 Determination During a study of the cure of phenol alcohols and one-stage phenolic resins i t became very important to be able to determine their methylol content. By reaction of phenol alcohols and similar materials containing methylol groups with an excess of phenol, i t was found that a mole of water is formed For each methylol group. When benzene is added to the phenol containing the sample and refluxed, the water formed b y reaction of the methylol group*
NTII, recently it riiiiplc iuc.1hoci h:w not been :tv:tilal)lefortleterniining the methylol content of phr1iol alcohols or phenolic resins containing methylo1 gt'oups. This has been due largely to the fact that a reagent which \vi11 rmct quantitntivc>ly with a niethylol group and yet not :ttt:trk the phenolic hytlrosyl group or I lit! benzene ring ha,=h c m tliflicwlt to find. 1,illeg and Osmond report th:it iodiiic, i n :ilkaliiie solut,ioli will oxidize a methylol group without attarking the phenolic groul) ( 8 ) . However, the iodin? i w c t s witli the ring hydrogens 0 1 t 1 1 ~ ~~ti(vioI, so that corrections for this side reaction brcomc nert!s>:try. Runk (10) has roportcd his inability to obtain rcllia\)lervsultr ivith this method and the nrithor has espericncetl pimilnr difticultiw. Sprung ( 1 1 ) ha. rhown that 0- and p-hydros\-l)enzyl :ilcohol react with 1~roniatc-bromidesolution to add :Itonis of lironiinc~---thatis, these phenol alcohols react with Ijroniine as if thc niethglol group were not, present. However, tho formation of a diphenylol methane b y c.oridrns:ition of a phenol nlcohol reduces the number of posit,ions reactive toward bromine I)y oil(' 1)t.r phenol nucleus for cacli metliylcnc hridge established. Thus, it' t,he quantity of fornialdchycio :itldrd to a phenol-forn~nldehyd(, i.cwt,ionmixture is known, t1etermin:ttion of the amount of formalclehyde reacted and t,he reduction in bromine absorption c:rusrtl Iiy cnndcnsation will give :in indirect measure of the methylo1 content. However, the nict,hod is limited, as Ruderman ( 8 ) h:w *hoivn that the methylol groups of most phenol alcohols, with the, esception of the two mentioned al~ovc,are not quantitatively displaced by bromine. Iarc niust also he exercised to see that the water contmt of t h r resin i?; accurately determined, if relinhle result' :irv t o tie obtained. Formaldehyde w r i c t i a-it11 phciiol t o liherate a molr or' water for each mole of aldehytlc rcwst.rd. While dry phenolic resina rontain very little unrractrtl forin:tldehyde, resins before dehydration often rontain free formaldehyde. In such cases a rorrection must, he matie for t h e unreactrti formaldehyde in the iv:ir*tion mixture. 4CKNOa'LEDGM ENT
The author is indebted t.o L. S.Moody for t,he saniplw i ) i ' oxllyloxy benzyl alcohol ant1 2,fi-bis-(liydro.uymeth~l)-~-chlori~phenol, and to Ii. R. Goldblum for his many helpful suggest,ioii.;. LITERATURE CITED
Claisen, L., and Eisleb, O., Ann., 401, 30-1 (1913). D'Alelio, G. F., "Laboratory Manual of Plastics and Sytii hr-tic. Resins," p. 28, New York, John Wiley & Sons, 1943. Einhorn, A., and Hamburg, A., Ber., 41, 24 (1908). Feith, F., Kunstsfofe ver Kunststoff-Tech. u. 4nweiid.. 34. 71-6 (1944).
Fischer, K., Angew. C h n . , 48, 394-6 (1935). Gladstone, M. T., private communication. Koebner, M., Chem.-Ztg., 54, 619 (1930). Lilley, H. S., and Osmond, D. W. J., J . SOC.Chem. I n d . ( L i i n don),66,425-7 (1947).
Ruderman, I. W., ISD. ENG. CHEM.,A N ~ L ED., . 18, 7 5 3 - 9 (1946).
Runk, R. H., Ind. Eng. Chem., 42, 2110-14 (1950). Sprung, M. M., IND.ENG.CHEM.,ANAL.ED.,13, 35-8 (1941 ) . Sprung, M. M., and Gladstone, M. T., J . Am. C h c n ~ h. e . , 71, 2907-13 (1949).
Ullmann, F., and Brittner, K.. Ber., 42, 2539-48 (1909). Weiler, M., and Berres. K., Cer. Patent 510,447 (1929). RECEIFED Deconihw 18. 1950.
