T H E J O U R N A L O F I N D U S T R I A L .1ND E N G I N E E R I N G C H E M I S T R Y
824
corresponds t o a n average saving of 40 per cent of what a corresponding Bunsen range would require. I t may also be assumed t h a t the latter would cost t h e consumer $35 a n d the former $ j o a n d t h a t gas costs $1.00 per 1000 cu. f t . a n d electric current I O cents per K. W. hour. The surface combustion range would consume per year j o X 3 X 300 = 4j,ooo cu. f t . of gas, while t h e corresponding Bunsen would consume 45,000 + (1.0 - 0.4) = 7 j,ooo cu. f t . so t h a t t h e saving of the former over t h e latter is 30,000 cu. f t . , worth $30 per year. From this is to be subtracted t h e cost of 900 hours of electrical supply, which must be estimated, This can be calculated from the power charts given, a n d it will be found t h a t for even low efficiencies of fan a n d motor not over 0.j ampere a t I I O volts or j j watts should be ample. I n fact actual measurement of the Regina vacuum cleaner set, illustrated o n the first range, Figs. 48 a n d 49, which had a delivery pressure twice a n d a n air volume about four times what was required, required 92 watts with all burners in operation a n d 90 with none! proving the excess capacity a n d t h e probability of operating with fans a n d motors designed for the service on less t h a n half a n ampere. Assuming t h a t a t the start no efficient fan a n d motor be available a n d t h a t t h e absurdly high consumption of 9 0 watts would be required for the necessary I O cu. f t . of air per minute a t 4-j inches water pressure, the electrical cost of operation would be I O X 901 1000 = 0 . 1 cent per hour, in round numbers, or $ 9 . 0 0 per year. This makes t h e net saving in operation $30.000 - $9.00 = $21.00 per year, a n d as the excess of first cost was assumed t o be $ ~ j . o oit would be paid off completely in 600 hours of operation, or if uniformly distributed in 81j2 months. One short way of disposing of the electrical cost is t o consider t h a t the gas saved b y a single t o p burner GASSAVING NECESSARY TO JUST P A Y COST O F ELECTRIC CURRENT E X PENDED FOR F A N OPERATING SURFACE COMBUSTION APPLIANCE?
----
-
Electric H.P.' Equivalent Amperes at required Equivalents by fan watts 1 I 0 volts 220 volts 0.01 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.09 0.10
7.46 14.92 22.38 29.84 37.30 44.76 52.22 59.68 67.14
0.11
82.06 89.52 96.98 104.44
0.12 0.13 0.14
0.06782 0.13564 0.20346 0.27128 0.33910 0.40692
0.47474
74.60
.
0.54256 0.61038 0.67820 0,74602 0.81384 0.88166 0,94948
Cu. f t . gas per hr. costing same as electric curCurrent at rent at $1.00 10 c. per per 1000 K. W. hour cu. ft. gas
0,03391 0.06782 0.10173 0.13564 0.16955 0.20346 0.23737 0.27128 0.30519 0.33910 0,37301 0.40692 0.44083 0.47474
0.0746 0.1492 0.2238 0.2984 0.3730 0.4476 0.5222 0.5968 0.6714 0.7460 0.8206 0.8952 0.9698
1.044
0.75 I .49 2.24 2.98 3.73 4.48 5.22 5.9T 6.71 7.46 8.21 8.95 9.70 10.44
will more t h a n pay for the electric current t o operate t h e entire range so t h a t for all burners in operation in excess of one the electrical current costs nothing. T h a t this statement is justified is indicated by the following, assuming the inefficient fan a n d motor t o be used t h a t costs 0.1 cent per hour t o operate. If the service of a standard ~j cu. f t . Bunsen top burner
1'01.
j, NO. I O
is preferred by a I O ft. surface combustion burner (ratio 1.j) t h e gas saving is j cu. f t . per hour, which is worth j X I O O O ~ I O O= 0 . j cent per hour, a net saving of 0.4 cent per hour. This shows how conservative is the general estimate above, t h a t other gas saving a t one burner will more t h a n defray t h e expense for current for t h e entire range, for under the conditions named the gas saving a t one burner is five times t h e cost of current for all of t h e m . I n t h e preceding table there is given a series of equivalents in gas saving, cu. ft. per hour, the value of which just balances various values of electrical horse power requirements of fan. CONCLUSIOS
I t is hoped t h a t thik review of the development of surface combustion will show t h a t it is now possible t o design rather t h a n merely invent apparatus, a n d t h a t such apparatus as commercial conditions may require may now be produced in no more time t h a n is necessary t o decide on t h e models t o be manufactured a n d t h e production of a n initial stock. However, there is no intention of leaving t h e impression t h a t t h e work of development is finished for i t is only just fairly started, a n d should be continued with corresponding improvement in appliances for the next half century. COLUMBIA UNIVERSITY, N E W YORK
METHODS FOR THE EXAMINATION OF NATURAL GAS FOR THE PRODUCTION OF GASOLINE B y E. S. MERRIAMAND J . A. BIRCHBY Received July 18, 1913
The production of natural gas gasoline from the casing head gas of t h e oil fields, by compression a n d cooling, has, within t h e last five years, grown t o be a very important industry. Through t h e failure of many plants t o obtain gasoline in paying quantities, i t was early recognized t h a t a preliminary examination of any proposed gas should always be made, a n d naturally the problem was put up t o the analytical chemist. Any one a t all familiar with t h e literature on natural gas will realize t h a t positive statements in regard t o the presence a n d quantities of the higher paraffines occurring in natural gas are not numerous. Ethane. propane, a n d b u t a n e were early found in natural gas, b u t no reliable figures could be given as to their amounts. I n fact from combustion d a t a alone only the total quantity of paraffin vapors present can be determined, a n d not which ones.' Generally t h e results are recorded on t h e assumption t h a t methane a n d ethane alone are present. The exact analysis of a mixture of five hydrocarbon gases does not seem possible, with t h e means available in a n ordinary laboratory. Fractional distillation a t -190' C. a n d - - I Z O O C. seems t o have given Lebeau a n d Damiens2 good results. The use of high pressur es in con ne c ti on with the critic a1 t e mp e r a t ur e of the vapors believed to be present might lead t o a more or less correct result. though the solubility of a gas in a liquid hydrocarbon must be taken into account. 1
3
G. A . Burrell, Bur. of Mines, Bull. 15, 67. Cornpi. r e n d . , 156, 144-7 and 325-7; Chem. Abslracts, 7 . 1338
Even if we h a d methods whereby t h e percentage of butanes a n d pentanes could be determined in a given gas, i t would still be a difficult matter t o calculate how much of each could be condensed t o liquid a t any given temperature a n d pressure. a n d when i t is found t h a t t h e 1-arious makes of compressors and condensers are not equally efficient, it can readily be seen t h a t t h e chemist should be extremely conservative i n d cautious in his reports. I n T-iem of these facts i t is evident t h a t t h e most logical method t o pursue is t o obtain gases from plants where t h e production is known, a n d t o examine these gases b y methods which will respond t o t h e presence of t h e more readily condensible hydrocarbons. I n this way empirical relations between certain physical a n d chemical properties of t h e gases and t h e yields in actual practice can be established. a n d a probable yikld for a n y unknown gas can be predicted. -4 second method is t o construct a small compressor so t h a t a n y gas m a y be subjected t o a n y desired pressure or a n y degree of cooling. We have proceeded along both these lines, a n d t h e object of this article is t o describe t h e methods which we ha\-e found most suit able. I t may be of interest t o describe first some methods which we tried a n d discarded. Fivsl.-By passing t h e gas through absolute alcohol i t was believed t h a t t h e heavier hydrocarbons mould be partially dissolred. If this alcohol be then diluted with water, t h e hydrocarbons, being insoluble in a n d lighter t h a n water, would separate a n d their TTolume could be determined. This method was used b y Bun-
the method did not seem t o respond with sufficient delicacy t o t h e presence of t h e heavier hydrocarbons. The first method which showed promise w a s t o determine the solubility of t h e gas in absolute alcohol.’ T h e following solubilities are given in U-atts’ dictionary: 1 volume 1 volume 1 volume I volume
of of of of
alcohol alcohol alcohol alcohol
dissolves dissolves dissolves dissolves
0 . 5 2 3 vol. CHd a t 0’ C 1 , 5 vols. C ~ W S . 6 . 0 vols. C3H8. 1 8 . 0 vols. C~HI..
The process used was simply t h a t of Hempel for determining benzene vapors in illuminating gas: I cc. of absolute alcohol mas placed in a Hempel explosion pipette over mercury? 100 cc. of gas introduced and t h e decrease in volume noted after three minutes shaking. This decrease will be due t o a slight extent t o methane, a n d in an increasingly greater measure t o ethane, propane, etc. The I cc. of alcohol will be completely saturated n i t h CHI, probably nearly saturated with C,HR. b u t will in general not be saturated with t h e heavier constituents which are present in smaller amounts rind which have a far higher solubility. If, then, a second quantity of IOO cc. of fresh gas is shaken with this same I cc. of alcohol, t h e decrease in volume this time will lie clue mainly to t h e heavier yapors present. Since alcohol has an aplirecialile 7-apor tension, is also a n oxygen-containing b o d y . a n d should therefore be a poorer solvent for hydrocarbons t h a n another hydrocarbon, we soon discarded i t s use a n d used I cc. of kerosene instead. The results obtained by t h e use of kerosene have proven of great value.
TABI .E I so.
26 27 30 33a 33b
-, I
80 84 85 96 99 117 125 135 136
D 1.305
1.276 1.41 1.24 1.12 I 244 1.202 1,004 0.931 0.799 0.795
I.08i 1.398 1.31 1.142
P e r cent air
D’
A
B
1.406 1,383
13.6
6.0
11.1
5.4
...
19.0 11.2 6.6 12.9 6.8 2.4 3.i 4.0 3.4 6.9 16.0 14.0 8.8
6.8 5.7 1.9 4.3 3.2 1.1 0.4 1.1 1.1 1.4 7.1 4.4 2.9
25.0 38.5 0.0 44.0
1,429
..
...
0.0 61 . 0 34.0 27, 5 0.0 0.0 0.0 26.5 0.0 17.0
... 1.515 1.005 0.905
... . . ... 1.542
... 1,171
Olive oil A/B absorption 2.27 2.06 2.79 1.97 3.48 3.0 2.12 2.18 9.2 3.63 3.1 4.92 2.25 3.18 3.04
15.8 13.2 26.2 14.5 9.2 19.0 8.8 5.2 4.i 5.8 4.7 10.6 21.4 16.8 9.0
hf 67 66 65 60 58 58 69 73 48 58 69 52 60
YIELD 5.0 5.0 8.0 5.0
80 YO 80 80
..
...
4,0
.
,..
.. 0.75 0.0 0.50 0.25 0.0
5.0
57.5
1.0
61
2.5
sen in showing t h e presence of benzene in illuminating gas (Hempel-Dennis, “Gas Analysis”). I n t h e case of natural gas, hoTvever, owing t o the rapid escape of t h e lighter constituents , such brisk effer \-es ce ii ce occurred on diluting t h a t t h e heavier hydrocarbons were carried off. Elyen with ice water and in a closed vessel no reliable results could be obtained. Secor,d.--By treating t h e gas with a suitable high boiling oil, such as lubricating oil. t o absorb t h e vapors, a n d then distilling t h e mixture. i t was sought t o regain t h e lrapors. The hydrocarbons t h u s obtained could not be condensed satisfactorily. ?‘liiid.-By combustion. This method as mentioned above gives t h e total paraffins only, a n d while a rich gas can easily be distinguishecl from a poor one?
PRESSERE
100 250 250 200
180
REXARHS “ G a s p u m p gas” “ G a s p u m p gas” “ G a s p u m p gas” “ G a s p u m p gas” 3 3 a after compression T a k e n f r o m well under 5 0 Ibs. pressure \7ield 6 t o 7 after eliminating air a t 225 Ibs. T h i s gas had been through a plant a t 250 Ibs. Unsuccessful plant Unsuccessful plant G a s had been through a t 180 Ibs.
110 not known
I n Table I , the figures under A denote t h e number of cc. of gas absorbed by I cc. of kerosene, under 13 t h e absorption when a second IOO cc. of gas is shaken with t h e same I cc. of kerosene. B is, of course, in every case, smaller t h a n A , and is proportional t o the heavier constituents present. F e have found t h a t the value of B approximately represents t h e yield of gasoline in gallons per 1000 CLI. f t . of gas. When €3 is small i t will exceed the yield; when high it will fall below t h e yield. The ratio of X t o €3 is also of significance, as can be expected from general principles. If t h e h y d r o c n b o n s causing B are of high molecular weight they should be more readily condensible a n d show a higher solubility. The first 100 c r . of g a s I
G . A . Burrell, ioc. cii.
826
T H E JOL*RilidL O F I N D L - S T R I A L A,VD E,VGINEERING C H E M I S T R Y
therefore will not come so near to saturating the I cc. of kerosene, a n d B will be greater t h a n would be t h e case if more volatile constituents were present. T h e ratio of A to B should show something about the condensibility of t h e vapors a n d the pressure needed t o liquefy t h e m . The determination of A a n d B should, of course, be made a t a fixed temperature; the figures given refer t o 2 0 ’ C. Further information in regard t o the nature of the hydrocarbons can be gained very simply. It is easy t o determine t h e mean molecular weight of the vapors which have dissolved in a n y solvent. All we need to know is their volume a n d weight under t h e temperature a n d pressure prevailing. For this determination we have used a small vessel of the shape shown in Fig. I. This contains some glass beads t o increase t h e surface, a n d is charged with j cc. of olive oil. We have used olive oil rather t h a n a mineral oil since i t has practically a n unvarying constitution, is non-volatile a n d does not foam. T h e olive oil is first saturated with our city gas, which, PIG.1 pears to consist of aboutfrom jj per combustion cent methane d a t a , aapnd
*
2 5 per cent ethane; the gas in the upper part of the bulbs is driven out by aspirating through a small a m o u n t of air, a n d t h e whole is weighed. T h e bulbs are then connected between a gas burette a n d Hempel pipette filled with water, a n d I O O cc. of gas are slowly passed back a n d forth a dozen times or more, or until no further gas is absorbed. The decrease in volume is noted a n d the increase in weight of the absorption bulbs. Readings of the temperature (which we have always kept as near 2 0 ’ C. as possible) a n d pressure then give all the necessary data for computing the molecular weight of t h a t part of t h e vapor which has dissolved in t h e oil. An example will make the method of calculation clear. In gas No. 26 of Table I , 15.8 cc. of gas were dissolved by t h e olive oil, a n d the oil thereby gained in weight 4 2 . 9 mg. T h e temperature was 2 0 ’ C., a n d the barometric pressure (corrected for the vapor tension of water) was 740 mm. At o o a n d 760 mm. t h e I j . 8 cc. reduces t o 14.32 cc. T h e weight in milligrams of 2 2 . 4 cc. of a n y gas measured a t o o and 760 mm. is equal t o t h e molecular weight M. Therefore, 14.32 : 42.9 = 2 2 . 4 : M. hl is 6 7 in this case. T h e molecular weight of butane C4H10is j 8 , a n d of pentane C ~ H I ?is 7 2 . It seems certain, therefore, t h a t this gas contains a t least I j . 8 per cent of condensible hydrocarbons corresponding t o butane a n d pentane. T h e absorption is, of course, by no means quantitative. It will v a r y for one thing with the amount of olive oil used. Using mixtures of air a n d gasoline vapors of known composition we have found it possible, using j cc. of oil, t o recover from 40 t o 60 per cent of t h e vapor present, according to the volatility of t h e gasoline used in preparing the mixture. I n a n y case the figure thus obtained for the molecular
Vol.
j,
NO.
IO
weight of the condensible vapor is of value. From i t we can draw conclusions as t o t h e pressure needed a n d as t o t h e quality of t h e gasoline obtainable. A low molecular weight would mean a very lively condensate; a high figure would indicate a less volatile gasoline. As a rule t h e ratio of A t o B is also consistent with the molecular-weight determination, a high M going with a low ratio. T h e determination of AI also enables one t o tell whether a gas has been subjected t o pressure. These few simple determinations together with t h e density of t h e gas a n d determination of the air present, when checked upon gases where t h e production is known, enable one t o draw a fair conclusion as t o t h e probable yield of a n y gas. I n Table I are given the results of examination of gases from a number of plants. D gives the density of t h e gas, taking air as unity. When air is present, t h e density of the gas itself, D’, can be calculated from the formula: IOOD-70air
D’=
IOO
-70 air
L-nder yield is given the number of gallons of gasoline which the operators claim t o be making per 1000 cu. f t . of gas. Nos. 26, 2 7 , 30 a n d 33a are all “ g a s p u m p
FIG.2
gas,” i. e., are obtained from the wells by use of a vacuum. This process favors t h e evaporation of t h e lighter constituents from the oil, a n d usually gives a rich gas requiring only moderate pressures: 33b is the same gas as 33a after i t has been through t h e plant a t 80 lbs. pressure. The change in the figures for A a n d R a n d their ratio is quite marked. No. 84 is from a plant which is barely making expenses. No. 8 ; is gas which has been through a plant a t Z ~ lbs. O
OCt.,
I913
T H E J O r R N A L O F I N D C S T R I A L A N D E iVGINE E RI N G C H E M I S T R Y
M is extremely low a n d A/B very high. is gas which has been through a t 180 lbs. Nos. 96 a n d 99 are from unsuccessful plants. No. 80 m-as examined by us and we reported a probable yield of 2 l , ? gals., b u t stated t h a t if t h e entrance of air could be avoided a yield of 6 gals. might be expected. T h e operator went over his lines finding numerous leaks which he repaired, a n d is now making 6 t o 7 gals. per 1000 cu. ft. For further tests we have constructed a small compressor by which the exact yield under a n y working conditions can be obtained. T h e results obtained in this way are free from a n y uncertainty, a n d the approximations of t h e analytical methods and personal equation of the analyst are done away with. I n the accompanying Fig. 2 . A a n d A’ are 2 cylinders of polished brass tubing 4” X I O “ . each fitted with a bronze cap B, B’. screwed a n d soldered on. Each cylinder is provided with a piston C, C’, with close fitting leather cups above a n d below, a n d a piston rod, D, D’, provided with a stuffing box, E, E’. Each cylinder is provided with a water jacket which can be pressure.
No.
11;
827
into the cylinders on top of the pistons; the pistons are then forced u p t o the top of the cylinders. The excess water is thus forced out, a n d only enough remains t o fill the space between the pistons a n d caps of the cylinders. Connection is now made with the gas to be tested. By opening the valves G, G’ a n d pressing on the stirrups the pistons are drawn down, a n d t h e cylinders filled with a measured volume of gas. The graduated glass tube J is now attached a n d it a n d the condenser I are surrounded by the cooling water. Boiling water is placed in the jackets, the valves G, G’ closed, a n d hot water is pumped into cylinder A’ through F’, forcing t h e piston up a n d driving t h e gas over into A. T h e rise of the water into the tube H’ shows when t h e gas is all out. The valve F’ is now closed. All t h e gas is now in A. The valve G is closed a n d hot water is pumped into A, compressing the gas. The gauge shows the pressure. When the desired pressure is obtained, the valve G’ is opened very carefully, allowing t h e right-hand piston t o descend. T h e p u m p is now operated a n d the pressure kept constant. The gas thus passes slowly
TABLSI1 NO.
D
Per cent air
145
0.94
0.0
D’
-4
B
...
i.3
2.5
A/B
Olive oil absorption
M
2.92
8.8
69.0
Empirical formula Calculated from combustion d a t a D
Cr.66H5.59
0.88
146
1.062
i.0
1.068
8.5
3.2
2.66
10.4
63.5
Cr.r,Ha.,o
1.045
147
0.95i
0.0
...
6.6
2.3
2.87
7.9
68.0
C~.aiHr.ir
0.947
148
0.802
0.0
...
3.6
0.7
5.15
4.2
CI.~~HI.II
0.803
Pressure Yield 1.35 2.26 2.94 1.49 2.76 3.58 1.33 2.34
3.00 105?
149
0.958
0.0
...
5.9
2.2
2.68
6.5
76.0
Cx.a.Hr.a,
161
0.886
0.0
...
5.8
1.6
3.62
6.9
69.0
. .. . . . . .
filled with hot water. I n the base of the cylinders are two openings, F , F’ a n d G, G‘, which serve for the entrance a n d exit of the hot water used for exerting the pressure. By the use of a small boiler testing p u m p a n y pressure up to joo lbs. can be exerted on the gas, a n d the pressure can be controlled accurately b y the gauge which is placed between t h e pump a n d cylinders. A n u t a n d sleeve press the small glass tube H, H ’ into a gas-tight connection on the cap of each cylinder. T h e sleeve is partially cut away so t h a t the glass tube can be observed. From cylinder A leads a small capillary copper tube, the lower part of which is wound spirally a n d serves as t h e condenser I. This passes through a small brass disk against which is pressed a graduated glass tube, J , which serves t o collect t h e condensed liquid. This glass tube is seated tightly with a rubber washer, as are also the tubes H a n d H’. Through this brass disk passes another tube, K , which conducts the spent gas to t h e other cylinder. T h e tube J a n d condenser I are set in a jar of water of a n y desired temperature. The method of operation is as follows: the graduated glass tube J is removed a n d a little water is drawn
0.955
...
0.36 0.64 0.91 1.43 2.45 3.12 0.79 0.99 1.26 1.52
Lbs. 100 200 250 100 200 300 100 200 300 100
Cooling temperature 7’ C .
8‘ C.
70
c.
15°C.
200 300 100 250 350 100 150 200 300
8 O
C.
l5’C.
a t the desired pressure through the condenser a t t h e desired temperature, a n d any liquid forming in the condenser is carried down a n d collects in the glass tube, which is graduated so as to read directly in gallons per 1000 cu. f t . of gas. The spent gas passes over into cylinder A‘. After t h e gas has passed through a t a n y pressure it can be transferred back by opening G a n d pumping in a t F’, and put through again a t a higher pressure. As many readings can be made as desired. The use of hot water in the jackets a n d pump prevents t h e condensation of gasoline in the cylinders, though i t is always advisable, especially in the case of rich gases, t o increase the pressure by easy stages. If the pressure were raised to 2 0 0 lbs. a t the start some liquid might condense in t h e cylinders and not get over into t h e measuring tube. We have found t h a t all the gasoline obtainable a t a n y pressure is thrown down by one operation, a second trip through a t the same pressure not yielding a n y more liquid. We have found this apparatus to work very well, a n d have examined a good many samples of gas by the
,
828
T H E JOl’R.VdL
O F I z V D l ’ S T R I d L d.VD EaVGI-VEERILVG C H E A I f I S I R Y Vol.
absorption methods and the compression method. T h e results of a few of these tests are given in Table 11. Under yield is given t h e quantity of liquid condensed b y use of the .compressor described above. This figure is t o be looked upon as an upper limit. T h e yield on the large scale will be less t h a n t h e figure given. owing t o leakage, eraporation losses, imperfect cooling, etc. The combustions were made over mercury, using oxygen and a heated platinum spiral. I n almost every case t h e figure for hydrogen is slightly greater t h a n t h a t corresponding t o a paraffin of t h e This i s undoubtedly due t o formula CnH2, + 2. experimental error, as i t is well established t h a t natural gas does not contain free hydrogen. The density of the gas calculated from the empirical formula agrees fairly well with t h e observed D. SCUMARY
I. X few simple empirical tests are given whereby t h e approximate quantity of gasoline obtainable from natural gas can be determined. 11. A small testing compressor is described. 111. Some typical analyses and tests are given. MARIETTACOLLEGE MARIETTA 0.
T H E CHEMISTRY O F ANAESTHETICS, V.: E T H Y L CHLORIDE B y CHARLESBASKERVILLE A N D W. A . HAMOR
CHEXICAL HISTORY
Ethyl chloride (“sweet spirit of s a l t ; ” uetlzq’iu~iz c h l o v a t u m ; a e t h y l i s c h l o r i d u w t ; a e t h e r c h l o r a t u s ; aether h y d r o c h l o r i c u s s e u muriaticzis; “hydrochloric ether;” chlorhydric ether; chloro-ethane; mono-chlorethane; chlorethyl; c h l o r a t h y l ; clzlor~asserstoffaither; leichter salzather; chlorure d’ethyle; ether chlorhydrique; “chelen” or “chelene;” “kelen” or “kelene;” “anodyn o n e ; ” “antidolorin; ” “ethylol;” “loco-dolor;” etc.) was first obtained in alcoholic solution by Basil T‘alentine ( p s e u d o - ) . * “Sweet Spirit of S a l t ” was well known t o the later chemists. Glauber, for example, referred t o i t in 1648. Ludolff stated, in I j 4 g I 3 t h a t on heating alcohol with sulfuric acid a n d sodium chloride, a distillate was obtained which, when treated with lime, yielded a n “ e t h e r ; ” but he endeavored in vain t o obtain a similar compound b y the action of hydrogen chloride (“muri1 Read a t t h e regular June meeting of t h e ICew York Section of t h e American Chemical Society, 1913 2 H e described its preparation t h u s (“U’iederholung des grossen Steins der uralten Tt’eisen,” ed. Petraeus, p. i 2 ) : “ T h i s I also s a y t h a t , when t h e spirit of common salt unites with spirit of wine, a n d is distilled three times, i t becomes sweet a n d loses its sharpness.” I n his Lasl Testament (“Basilius T’alentinus,” ed. Petrueus, p. 786) h e also says: “ T a k e of good spirit of salt which has been well dephlegmated a n d contains n o watery particles, one p a r t ; pour t o this, half a p a r t of t h e best a n d most concentrated spirilus vini which also contains no phlegma or vegetable mercury.” Valentinus goes on t o s t a t e t h a t this mixture must h e repeatedly distilled, a n d t h e n “placed in a well-closed bottle a n d allowed t o s t a n d f o r a m o n t h or until i t has all become quite sweet a n d h a s lost its acid taste. T h u s is t h e spiritus salis et i’ini prepared a n d m a y be readily extracted ” I n 1739, Johann P o t t demonstrated t h a t “sweet spirit of salt’’ could be obtained b y t h e action of “ b u t t e r of arsenic” or “butter of antimony” (arsenic o r antimony trichloride) on spirit of wine. a n d other chemists f o u n d t h a t other metallic chlorides might be employed for t h e same purpose. Rouelle, in 1759, found t h a t ethyl chloride resulted from t h e action of sulfur chloride, phosphorus pentachloride. aluminum chloride, ferric chloride, stannic chloride, etc., on alcohol. 3 Die in der J f e d i c i n siegende Chemie. . . . , ,, E r f u r t . 1746-9.
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atic gas”) on alcohol. BaumC was also unsuccessful in this direction, but Woulfel obtained the preparation in this way, a n d i t was afterwards prepared a n d sold b y an apothecary in Germany under the name of “Basse’s hydrochloric e t h e r ” (1801). H I S T O R Y O F I T S U S E AS A N A S A E S T H E T I C
Flourens2 drew attention t o the anaesthetic properties of ethyl chloride in 1847, and Heyfelder. in the following year. first administered t h e vapor for surgical purposes . Cns at i sf a c t or y sy mpt o m s oft en a cco m panied its administration a t t h a t time, these effects being attributed t o imperfections in t h e manufacture a n d t h e consequent presence of impurities. The use of t h e agent as a general anaesthetic was abandoned until 189j, since which time i t has rapidly gained in favor. This is principally attributable t o the improved methods of administration. a n d t o an increase in t h e knowledge of its properties a n d physiological action: and last, but not least. t o improvements in its manuf acture.3 Ethyl chloride may be regarded as ethyl alcohol (CHaCH?OH), in which the O H has been replaced b y C1, hence t h e formula CHqCH2C1,which w a s established b y Colin and Robiquet..‘ “Alcoholic (or ‘alcoholized‘) muriatic e t h e r ” is a solution of ethyl chloride in an equal amount of alcohol by volume. I t has been used as an internal stimulant in doses of 0 . 6 t o I . 8 cc. CSES
So far ethyl chloride has not been used technically. although Palmer5 called attention t o its advantages (and disadvantages) as an industrial refrigerating agent. I n medicine i t is used for ( a ) general anaesthesia (by inhalation) ; ( b ) local anaesthesia (by external application, i n effect refrigeration); a n d ( c ) diagnostic a n d therapeutic purposes. PREP 4 R A T I 0S
-4s noted, ethyl chloride may be rcgarded as ethyl alcohol (C*H50H), in which the hydroxyl has been replaced b y chlorine. Ethyl alcohol is t h e raw product from which i t is usually made, although ethyl chloride results in the regulated chlorination of ethane,6 o n treating acetic a n d other ethers with hydrogen chloride, b y the action of hydrochloric acid on ether in sealed tubes,’ and b y t h e action of chlorine on ethyl iodide. I n actual practice, ethyl alcohol is mixed Phil. T r a n s . , 1767, 520. Hewitt, ‘:Anaesthetics,” 1907, 11. 3 I n 1880, a committee of t h e British Liedical Society reported t h a t ethyl chloride was n o t safe t o employ as a general anaesthetic, owing t o its liability t o produce respiratory failure a n d convulsions. I n 1898, i t was stated in Sajous’ A n n u a l : “ W e would also warn against its (ethyl chloride) use f o r t h e purpose of inducing general anaesthesia, as the dangers incurred therefrom a r e too great.” Interest in its use was revived in t h e same year, however, b y t h e reports of Lotheisen, a n d i n 1901 b y McCardie, who cited a large number of successful cases in general anaesthesia. T o quote Dodge [Boston .\fed. S u r g . J . , 1909, 234 (February 2 5 ) l : “It is believed t h a t t h e bad results obtained earlier were d u e partly t o impure preparation of the drug, as well a s improper methods of administration. W a r e ( J . A m . M e d . A s s n . , November 8 . 1902) directed attention t o t h e f a c t t h a t preparations marketed in this country in 1902 contained methyl chloride t o facilitate evaporation. 4 A n n . chim. phrs., [21, 1, 343. 6 Eng. Digest, 6 , 262. 6 Darling, A n n . , 160, 216; Schorlemmer, ConzPi. r e n d . , 68, 703. 7 Berthelot. 1
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