Document GKGRkE3eMyJkZ8n0e8YeQQX4v

532 G. W. JONES been reported, the lowest apparently reliable one has been taken, after du consideration has been given to the size of the apparatus, the composition of the surface that came into contact with the heated mixture, and the method used t determine the ignition temperatures. C. IGNITION TEMPERATURES IN AIR AND OXYGEN From an industrial standpoint the minimum ignition temperatures of com' bustibles in air are what is desired, although occasionally their ignition tempera tures in pure oxygen are desired. It is also of interest to compare the ignitio' -temperatures of combustibles in both air and oxygen, since numerous reference dealing with ignition temperatures have reported results in which the ignitio1 temperatures in oxygen were sometimes higher than in air. Such reported results' appear very unusual because combustibles heated in pure oxygen to reaction temperatures should react and oxidize at a higher rate and therefore ignite at a lower temperature in oxygen than in air. The results given in Table 4, based on studies that were carried out unde similar conditions, prove rather conclusively that combustibles have lower ignit tion temperatures in oxygen than in air. III. Flash Points .. The fash point may be defined as the minimum temperature at which a liqui gives off vapor sufficient to form a flammable ..mixture-in -contact -with-air-i-I-twi" a rather rough yet quick way of measuring the relative combustibility of volatT* liquids and, in turn, determines the approximate temperature below which codi bustibles may be stored and used without creating explosive atmospheres. In general, the higher the flash point of a liquid, the greater its Bafety in respect to; fires and explosions. It should be emphasized, however, that the flash point alone "C. E. H. Bawn, J. Chem. Soc., 1933, 145. / ** A. H. Nuckolls, Underwriters' Lab. Card Data Service, Chicago. "H. B. Dixon and H. F. Coward, J. Chem. Soc., 95, 614 (1909). " A. G. White and T. W. Price, J. Chem. Soc., 115, 1462 (1919). ** C. W. Sortman, C. W. Beatty, and S. D. Heron, lnd. Eng. Chem., 33, 357 (1941). " Table of Common Hazardous .Chemicals. Natl. Fire Protect. Assoc., Boston. 1949. ----- J?-Q^-'^fy-JonesrW-rPrYKBt;''WrErMiller7'and',R:'E71Se5nedy, V. S. Bur. Mines-Se Invest. No. 3234, 1935. "H. F. Coward, J. Chem. Soc., 1934, 1382. "P. Laffitte and G. Baret, Bull. soc. chim., 51, 281 (1932). "National Board Fire Underwriters Research Report, No. 4, New York, 1947, _____."6. WrJon6S"and-M;-G; Zabatakis-IL.il-B.ur-Jlfmea-RB7it^Ittgstr:'No-4.fi7:i--19S" "A. Grebel, Mem. et eompt. rend. trav. soc. ing. civile France, 83, 35 (1930). "* J, M. Weizevich and L. B. Turner, lnd. Eng. Chem., 27, 152 (1935). 1WE. Mack, C. E. Boord, and H,N. Barham, lnd. Eng. Chem., 15, 963 (1923). "* J. Baron and P. Laffitte, Compt. rend., 206, 1386 (1938). " A. Egerton and 8. F. Gates, J. Inst. Pet. Technol., 13, 244 (1927). hazards of combustible gases and vapors 533 TABLE 4 Ignition Temperatures of Combustible Gases and VaporB in Air and Oxygen Minimum ignition temperatures jSfifi'., Sufficetal Name gSKcetie acid. W& anhydride '"vl bromide j chloride yl acetate nzoic acid onzyl alcohol !!utadiene tane butane Stene-l Lalcohnl__ . ^tyl alcohol Butyl alcohol Butyl alcohol .lamina jitylasnine Blbenzene Qblitylbenzene jdutylbenzene BuJyfaldehyde ^f.hion disulfide bdn monoxide llfeigen ycf^bpane ifiBflae piloTobenzeno ichloro-n-bu tane _,iethylbenzene Jicthylpcntane neihylamine tgiiiimethylbutane 2j5@unethylbutane Formula C.H0, CiHiO C,H.O, C.H.O, C.H.0 C,H,0 CiHjN CjH,0 C,H,N CiHtBr CiHsCl CtHj.Oi CrHflOj C,H,0 C.H, CiHio C,H,s C,H, CjHmO ca!o C,HuO C,H,,,0 C,H,,N C,H,,N CmHh c,,hn CioHh CiHwOj C.H.0 CS, CO C,N, "c;fc... C,H, Ci0H GiBiCU C4HaCls CioH C,Hto C*H7N CtHii CftHu In air In oxygen Ref. Ref. e -p C. no. o p C. no. 446 230 73 345 174 349 176 74 221 105 1022 550 73 914 490 738 392 76 682 361 1042 561 77 . 905 485 453 234 30 439 226 898 481 47 860 460 712 378 80 658 348 73 74 73 76 73 30 47 73 705 683 909 676 1064 802 784 761 864 374 295 487 358 573 428 418 405 462 30 586 308 30 516 269 73 759 404 10 453 234 73 1033 556 80 704 373 73 635 335 75 542 283 10 606 319 30 30 73 10 73 82 73 73 10 723 653 813 763 892 694 712 774 802 784 384 345 434' 406 478 312 378 412 428 418 10 590 310 80 622 328 80 687 364 75 ' 711 377 73 860 460 31 536 280 75 626 330 75 527 275 75 588 309 75 700 371 10 82 86 73 73 31 10 30 30 30 633 446 248 1130 1562 334 230 120 610 850 31 540 282 31 73 403 206 73 88 225 107 88 89 1090 588 106 92 1492.,,..,811. 92 500' 928 406 1198 529 594 806 554 756 260498 208 648 276 312 430 290 402 76 68 75 31 73 31 75 75 73 489- ..--254- .....30 - 849 454 68 396 202 30 1123 606 31 482 250 73 554 290 ,31 590 310 38 432 222 38 655 346 73: 797 425 788 420 30 73 620 271 568 298 .39 73 (continued)