THE JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
704
Estimate 1 was based upon the assumption that one cyanizing retort would be capable of producing cyanized briquets of 20 per cent sodium cyanide content a t the rate of 7 Ibs. sodium cyanide per hr. and that this cyanide could be converted into ammonia with 85 per cent recovery. This would give 50.4 Ibs. of ammonia per retort per day. It would be necessary to keep 198 cyanizing retorts in operation. Estimating the life of a retort as 15 days, 215 retorts would be needed in the installation. Estimate 2 was based on the assumption that each cyanizing retort would produce briquets of 23 per cent sodium cyanide content at the rate of 8 Ibs. sodium cyanide per hr., and with 95 per cent ammonia recovery 158 cyanizing retorts
Vol. 14, No. 8
would have to be kept in operation. A total of 170 would have to be installed. Fixed charges were based upon cost of construction of the government cyanide plant a t Salt~ille,~ and calculated for amortization of plant (a) in 3 years, (b) in 5 years, (c) 15 per cent annual depreciation. Estimated cost of materials were as follows: Coal for fuel at
$ 4 . 0 0 per ton
Coke (low ash) at 25.00 per ton Iron at 60.00 per ton 35.00 per ton
Soda ash at
All costs were worked out in detail. 9
LOC.
Cil.
Preparation of Alpha, G a m m a Quinolines-I'8"s '
2,4-Dimethyl-6-Ethoxyquinoline : An Improved Method for Its Preparation By S. Palkin and M. Harris COLOR LABORATORY, BUREAU oP CHEYISTPY, WASAXNOTON, D. C.
The VQhe of the dicyanine dyes for spectrophotographic work, and their continued absence from the American markets led to an investigation of the preparation of the quinoline intermediates for these dyes, with a view to developing a commercial process more suitable than those now available and to working out some means of increasing the yields. The steps involved in the recovery of the pure quinoline derivatirres constitute by far the greatest dificuIties in the preparation of these or, y-quinolines. requiring repeated steam distillations or ether extractions. This is in a large medsure due to the tar formed i n the synthesis. The method described differs essentiaUy from the former methods f n the treatment of the reaction mixtures after the synthesis and the recovery of the pure base.
an excess of strong sodium hydroxide. When the oil has risen to the top (several hours are required) the aqueous layer is drawn off and the oily base subjected to vacuum distillation (30 to 70 mm). After removal of the water, the oil is collected to about 225' (30 mm.). This "crude base" distillate is treated on the steam bath with an equal weight of acetic anhydride and poured gradually into 3 1. of water. Most of the primary base and the hydro base is thus converted into insoluble acetyl compounds, which are removed by fitration after solidification. The cool filtrate is neutralized
HE condensation of ethylidene acetone with aniline, discovered by Baeyer,4 was used, with modifications, by Mikeska, Stewart, and Wise5 for the preparation of 2,4-dimethylquinoline, By the substitution of p-toluidine for aniline in the condensation, Pfitzingers prepared a,ydimethyltoluquinoline (or 2,4,6-trimethylquinoline). Using p-phenetidine as the primary base in this synthesis, Mikeska, Haller, and Adams' prepared 2,4-dimethyl-6-ethoqquinoline. They introduced improvements in the recovery and purification of the quinoline base. Ether extractions were substituted for steam distillation hitherto employed, and acetylation and diazotization were used for the removal of the unchanged phenetidine and hydro base.
T
SYNTHESIS
I
The synthesis proper is based on the Baeyer condensation and is carried out as described by Mikeska, Haller, and Adams.? The reaction product is treated as follows: A current of steam is passed through the reaction mixture (which has been diluted with 2 1. of water) for 0.5 hr. After cooling, the supernatant liquid is poured off and the tarry residue is washed several times with dilute hydrochloric acid which is added to the main liquid. The cool solution is treated with Received December 14, 1921. Published by permission of the Department of Agriculture. 8 Published as Contribution No. 58 from the Color Laboratory. 4 J . grakl. Chem., [2J38 (1886),401. 6 THISJOURNAL, 11 (Isle), 456. 6 J . grakt. Chcm., (21 32 (1885), 240; 121 36 (I888), 41. 7 J . Am. Chcm. Soc., 42 (1920), 2392.
I
1
I
0 PER CENT OF DISTILLATE -
RQ. 2-BOIrJNG
RANGESO F BASE AT 80 MX. ABTEB DIAZOTIZAT~OW X3A = extracted; X3B 3 not extracted
Aug., 1922
THE JOURNAL OF INDUSTRIAL
with strong sodium hydroxide solution, the solidified base is removed by atration and dissolved in twice its weight of concentrated hydrochloric acid and the cooled mass is diazotized. Upon dilution of the reaction mixture to about 4 1. with water, all of the base hydrochlorides dissolve, leaving a brown insoluble residue of phenacetin which contains the nitroso compounds. This residue is removed by filtration and a current of steam is passed through the filtrate for about 20 min. to decompose the diazonium salts to phenol. The cooled solution is filtered through cotton and neutralized. The base solidifies as a brown mass in about 1 hr., and is removed by filtration and distilled in vacuum. The base is recrystallized from 800 cc. of hot 18 per cent hydrochloric acid solution, filtered in three stages: viz., when the solution has cooled to 40' to 50" C., to room temperature, and to 0" C. The base is liberated from a water solution with alkali, filtered, and distilled at atmospheric pressure. Nearly the entire product boils between 314" and 316"+. It is almost white in color. The dry crystals melt a t 88" to 88.5' C.
I
220
.......... .......... ..........
I
I
I
l
3-BOILING
12ob
,o
OF DISTILLATE
RANGES OF BASE AT 30 M M . AFTER DIAZOTIZATION
210
I 30
I 40
PER CENT
TABLE I-EFFECT OF NITROSOCOMPOUND ON PURITY OB BASS AND COMPARISON OB FILTRATION AND EXTRACTION AS MEANSOF PURIFICATION
..........
j
I
0
About 4 k. of "crude base" were prepared. Boiling range curves, determined a t 30-mm. pressure, served as a working comparison for the products subjected to subsequent purification. A portion of this "crude base" was carried through the acetylation purification and vacuum distillation (30 mm.), and boiling range curves were plotted. This distillate served as a working sample for the study of diazotization and the influence of nitroso compounds. Table I records experiments which were carried out t o show the influence of the nitroso compound on the qu$y of the final base, and to test the feasibility of removingithis product by filtration, without resorting to extraction.
B. P. of Recryst. M. P. of Treatment Boiling Maximum B. P. at Product a t Recryst. of above Atmospheric Product Diazotized 205' C. 30 Mm. No. Mixture P e r c e n t C. Pressure ' C . C. REMARKS 210 314-316 8 8 . 5 Little tar: disxsANOcompound 15 tillate light removed by extraction in color with ether 220 315-317 Below 88 More tar: disabB Notextracted 40 tillate dark throughout AE11 Filtrate exNone 204 314-316 88.5 tracted with ether AEe1 Filtrate exNone 203 314-316 88.5 tracted with ether AEs1 N o extracNone 205 314-316 88.5 tiou AEd' No extrach-one 203 314-316 88.5 tion 1 Insoluble phenacetin with nitroso compound was removed by filtration.
I
I
PER CENT FIG.
PURIFICATION REACTIONS
1
I
,
1
I
I
FIG.4-BOILING
I
50
I
60
I
70
OF DISTILLATE
I
80
I I 90100
RANGESOF "CRUDE BASE"
of using an oxidizing agent to convert the hydro base to the desired quinoline. The results shown in Table 1II:are selfexplanatory. TABLE 111-EFFECT OF VARYING CONDITIONS I N THE SYNTHESIS FRACTION O F "CRUDE No.
BASE" WHICHDISTILS ~ ~ MM. ~ 3 0Yield of Yield To 160 200' UD "Crude" Pure Base Per cent Per cen? Grams Grams
Description of Experiment
Norma2 Normal as per method average
20
25
(105)' 310
(43.4)1
86.8
HCI Saturation-Tcmpsroturc Y1 Y21
Saturated acetone paraldehyde a t IO" C. Saturated acetone paraldehyde a t Z O O C.
27.0
I9
290
60
34.0
22
125
21
Moisture Experiments
Cond. with phenetidine (no water) 8 106 57.0 10 Cond. with phenetidine Yd HCl dry 22.0 150 22 40.6 with 20 Der The experiments recorded in Table I1 were made to de- Y6' Saturation 29.0 cent water 130 18 12 termine the optimum conditions for acetylation. Complete Y7B' HCl saturation and synthesis carried out removal of primary and hydro base by acetylation alone was 50.0 same day 10 122 12.5 Used arsenic acid as Y 81 not possible in any case. 25.0 oxidant 150 19 30 Heated "crude base" YlC TABLE 11-ERFECT OF VARYINGTIMEAND TEMPERATURE IN ACETYLATION with arsenic acid Impossible t o handle-too much tar TESTFOR PRIMARY AND HYDRO BASE 1 0.5 N quantities used. "Crude Base" IN RESIDUE Consumed by Period of Acetylation Acetylation Residual Nitroso Compound No. Steam Bath Per cent Phenacetin by Diazotization 53 AA 0 . 5 hr. Present Present By a bill passed unanimously by the House, the Department 51 BB 1 hr. Present Present of Conservation of the State of Louisiana is given regulatory DD 4 hrs. 45 Present Present 1 d a y (6 control over the natural gas fields, to prevent waste and to guarEE hrs.) 47 Present Present antee a supply of gas to any pipeline that may be built for the 2 days distribution of gas. The Department is specifically authorized FF (12 hrs.) 49 Present Present t o curtail the amount of gas used by carbon black mills whenever 0 . 5 hr. 53 other markets for domestic or industrial consumption are found. YI 129-130' With some tar Considerable Considerable
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