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Vol. 19, No. 3
Table 111-Analyses of Extracts before a n d after Vacuum Distillation
I ANALYSIS
Degree of concentrationa Alcohol, per cent by volume Total extractive Vanillin Lead number (Winton) Ash PzOr in ash, mg. per 100 cc. Total acidityb Acidity equivalent to vanillinb Aciditv other than vanillinb Reducing sugar as invert: Before inversior After inversion Sucrose (by copper) Nonsugar solids Vanilla resins Anisyl alcohol Piperonal b
1 I
SAMPL& A &XT. 1
Before 1.0 57.80 3.14 0.239 0.52 0.272 18.2 42.1 15.7 26.4 0.96 1.47 0.48 1.70 0.10 0 0
SAMPLE B EXT.
2
EXT.
After
After
Before
After
2.68 61.06 3.10 0.242 0.50 0.274 17.5 40.1 15.9 24.2 1.00 1.48 0.46 1.64 0.10
2.24 57.92 3.12 0.243 0.44 0.260 10.6 40.0 15.9 24.1 1.00 1.47 0.45 1.67 0.15 0 0
1.0 58.06 4.61 0.416 0.49 0.251 9.4 52.7 27.3 25.4 1.50 2.39 0.85 2.26 0.13
5.04 59.20 4.59 0.415 0.49 0.264 9.5 Tj0.1 27.3 22.8 1.51 2.41 0.86 2.12 0.13 0 0
0 0
0
0
I
SAMPLE C
S.4MPLE D
I
SAMPLE E
1
Before After
3 Before
After
0
0
0
0
I
After
0 0
I Before 1.0 58.50 2.89 0.137 0.52 0.278 11.8 35.8 9.0 26.8 0.69 1.03 0.32 1.88 0.08
0
After 16.54 58.94 2.91 0.130 0.54 0.275 11.8 33.7 8.5 25.2 0.72 1.02 0.29 1.90 0.08 0
1.0
26.11
+ ++ i
See Table 11. Cc. 0.1 N alkali per 100 cc. extract; other results in grams per 100 cc. unless otherwise noted
this was because the flavor of Tahiti vanilla is largely due to the volatile oil. The acetone extracts were distinctly inferior to the alcohol extracts in flavor. This was due, not to acetone, but apparently to acrid material extracted by the acetone but not by alcohol. The distillates were extracted with ether, which was evaporated spontaneously. The residues had the characteristic odor of the volatile oil of vanilla. The distillate from the Tahiti extract was rich in anisyl alcohol and piperonal. Owing to the minute proportion of volatile oil in the distillate, it is not feasible to extract it and return i t to the concentrate. Portions of the different original extracts were heated a t 98” C. in sealed flasks for 1 to 4 hours. On cooling t o room temperature and comparing with the original extracts, little or no difference in flavor and aroma was found. The 5 per cent dilutions were similarly heated, with little effect on the flavor and aroma. These experiments indicate that there is no appreciable decomposition of flavoring material, a t the temperature employed, but that loss of flavor is due to volatilization of flavoring material. Comparative Value of Vanilla Extract and Concentrates
It has been shown that when vanilla extract is concentrated there is a loss of volatile acids and volatile oil, and a corresponding loss of flavor and aroma, varying from 10 to 40 per cent, depending on the degree of concentration and kind of bean. This loss is not merely a weakening of the flavor, but is a change in the quality as well.
The liquid concentrates used by ice cream manufacturers and bakers are usually claimed to be a t least eight times standard strength; that is, 80 gallons of standard vanilla extract have been evaporated to 10 gallons. I n such a concentration approximately seven-eighths of the alcohol is recovered, or about 30 gallons of 95 per cent alcohol. This represents an apparent saving of about $1.60 on each gallon of standard strength vanilla. After January 1, 1927, the alcohol tax will be reduced $1.04 per wine gallon, and the apparent saving will be about $1.20 instead of 31.60. A second reduction in tax, scheduled for January 1, 1928, will reduce the apparent saving to about 80 cents. It is obvious that the sale of concentrated vanilla depends almost entirely on the high tax on alcohol. If the tax were abolished the saving on alcohol would be very little greater than the cost of distillation. On the other hand, the loss in strength must be considered. The net saving will, of course, depend on the market price of vanilla extract and the loss of strength in concentrating. At the present price of vanilla extract a loss of strength of 25 per cent would exactly counterbalance the saving on alcohol. Examination of a number of commercial concentrates disclosed that, when diluted to standard strength, they are, if free from adulteration, weaker in flavor and aroma than standard vanilla extracts. This deficiency in flavor and aroma was made up, in several of the samples examined, by the addition of flavoring materials foreign t o vanilla; the resulting mixtures were strong, but the flavor was not vanilla.
Recovery and Utilization of Waste Liquors in the Pulp Industry‘ By Umberto Pomilio BLETTROCHIMICA POJIILIO, NAPLES,ITALY
PPROXIMATELY 50 per cent of the weight of wood and annual plants used in pulp manufacture is obtained as pulp. This leaves a large tonnage of lignin and other carbohydrates, rosins, albuminates, etc., to run to waste. I n 1922 in the United States alone 5,550,000 cords of wood were converted into pulp, with the concurrent waste
A
1 Presented under the title “A-ew Lines for the Recovery and Utilization of Waste Liquors in the Pulp Industry” before the Dlvision of Industrial and Engineering Chemistry at the 72nd Meeting of the American Chemical Society, Philadelphia, Pa., September 5 to 11, 1926.
of many millions of pounds of organic substances. The pulp industry has long realized that the question of its wastes and by-products is a serious one, and although large sums have been spent a complete solution has not been attained, particularly with respect to the sulfite wastes. It is true that a small amount of alcohol and certain colors, medicinals, and explosive materials have been derived from the waste liquors from pulp mills, but the processes are complex, the yields low, and the costs high. Much of the difficulty is due to the low concentration of solids in the liquors
ILI-DUSTRIAL,AAYDESGI-VEERISG CHEMISTRY
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and to the considerable number of organic substances present', some of which have not been completely identified. From sulfite wastes some adhesives, tanning materials, and compounds for fire extinguishers have been produced and the lignin has been obtained in some instances to be used as fuel. Here again the consumption has been small and such processes as have been devised are applicable only to particular cases. Wastes from the soda or sulfate processes are t'reat'ed for the recovery of the sodium salts, but the organic constituents are either destroyed or utilized merely for their heating value, which cannot be regarded as wholly efficient. Though Rinman's process has been utilized to some extent, the fact is that many pulp mills, among which may be numbered large installations, have no recovery plant. and apart from economic considerations mills may a t any time be confront,ed with the necessity of treating their wastes to avoid stream pollution. The low concentration and complex composition of waste liquors are the principal difficulties in their economic treatment. The cost of concentrating such dilute liquors is high and the presence of fats, waxes, and resins, as well as pectic, mucic, albuminoid, pentosanic, and lignonic substances, intimately mixed and both in the free state or in combination with the reagent' chemicals used in the manufacture of pulp, as well as in true or colloidal solution, presents a difficult problem. Sulfite wastes have but 10 to 12 per cent of solids; that is, for each ton of cellulose 9 tons of liquor are produced, containing about 1.2 tons of solid matter. Wastes from the soda process vary from 8" to 9" B6., and may run as low as 6" to 7 " B6. From the sulfate process the wastes run about 15" BC., with about %50per cent of the solid matter combustible. Wastes from Chlorine Process
.
These circumstances point to the desirability 01: obtaining more concentrated wastes, containing less complex products, if an economic solution is to be found. The preparation of pulp by the use of chlorine gas offers such a possibility. According to one of the author's processes the non-cellulose constituents which can be separated from the vegetable fibers may be divided into four general classes-namely, neutral, acid, alkaline, and amphoteric. Also the trea.tment of wood may be carried out with four reagents-water, alkali, chlorine, and heat-all substantially effective, though in different ways. The process consists in. an alkaline impregnation of the wood occasionally following a preliminary hot-water treatment and then chlorination, washing with water, and finally mashing with alkali. The residual wastes of this treatment are as follows: TREATMENT H o t water Alkali impregnation Chlorination Alkaline washing
RSSIDUALLIQUOR Neutral Alkaline Acid washing waters (containing HCI) Chlorolignonic a n d alkaline
It will be seen that the non-cellulose substances are roughly grouped into various residual wastes from the consecutive steps of the chlorine process. I n the neutral liquors of the first treatment are the water-soluble materials which, especially with annual plants as the raw material, are Important. I n the alkaline liquors are the organic substances which, having an acid reaction, have combined with the alkali. Following chlorination the first wash water will contain only hydrochloric acid formed from the action of chlorine as an oxidizing agent or where it has been substituted for. hydrogen in the organic compounds. The final alkaline wastes will contain the oxidat'ion products and principally the substances of the lignonic type in the form of alkali chlorolignoiiic derivatives. The concentrat'ion of' the residual liquors is very low when the liquors are used but once in t.he treatment of fiber, but
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it is possible to strengthen these liquors for re-use and employ them a number of times, thereby obtaining a higher concentration of extractable substances than is possible with the ordinary wastes from the sulfite, soda, and sulfate processes. The wastes both from alkali impregnation and washing after chlorination are the most interesting, the loss of weight of esparto, for example, being nearly the same-25 per rentin both treatments. The alkali \Tastes have the following average compositions: Density Free NaOH Residue a t 1 0 0 - l l O o C. Mineral residue Organic substances (by difference)
22' t o 2 4 O Be 1 t o 1 5 per cent 35 t o 40 grams per 100 cc
20 t o 25 grams per 100 cc About 15 grams per 100 cc.
The mineral residue consists of sodium carbonate and sodium chloride, the latter forming more than 50 per cent, as the reagent employed is liquor from the cathode side of diaphragm cells, containing 130 grams of sodium hydroxide and 150 grams of sodium chloride per liter, or from the ma-li waters from the evaporators containing the same salt. lT7hen the treating liquor is made by diluting 50" B6. sodium hydroxide containing practically no salt, the waste water has the following composition: Density Free S a O H Residue a t 100-110° C. Mineral residue Organic substances (by difference)
About 20' BC. (sp. gr. 1 l:,j) 2.52 per cent 30 grams per 100 cc. About 15 grams per 100 cc. About 1.5 grams per 100 cc.
The boiling points of such waste liquors vary from 103" to 120" C., and from 5 liters of such waste having a specific gravity of 1.165 and containing 2.2 per cent of free sodium hydroxide there may be obtained 2 kg. of semisolid matter with 33 per cent of water. For each ton of esparto, returning the liquors to the process four to six times, 750 liters of 20" BC. residual liquors are obtained, bearing 15 per cent organic and 15 per cent mineral matter. Waste liquors from the alkaline wash are less concentrated with the present method of working. They have an average density of 4" BB. and carry 3 t o 4 per cent of residual matter, but it would not be difficult to bring them t o a somewhat higher concent'ration with 750 liters of residual liquor per ton of vegetable fiber treat'ed. The alkali impregnation washes from the treatment of such fibers as esparto and straw seem t'o offer possibilities for dry distillation with or without the addition of an excess of alkali (Rinman's method). The distillation products are mostly acetone, light and heavy oils, paraffins, tar, and pitch products, as well as combustible gases. The acetone must be considered as a derivative of the sodium acetate contained in the waste and, although methanol might be formed from lignonic substances, the amount is so small as to be of no practical importance. Hagglund's Process
Hbgglund's process would seem to be more suitable than Rinman's for the treatment of this material. Although Hagglund's process has not yet been put into industrial practice, it is interesting theoretically, as well as original. Hagglund proposes to submit the residual wastes of the soda process to a thermic treatment under pressure. Under such conditions higher yields might be expected than is possible with ordinary methods of dry distillation, including Rinman's excess alkali method. Hagglund's method2 is based on the t.echnology of the Bergius process for the decarbonization of cellulose in aqueous suspension a t high temperatures and is extended to the waste liquors containing lignin and saccharic acids, which are decomposed by heating under pressure. Tarry substances, gases, methanol, and 2
Papier-Fabr., 23, 493 (1926).
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some acetates are thus obtained, and a small amount of carbon is left as a residue. The process is equally suited to the treatment of wastes from either the soda or the sulfate process, but in the sulfate process compounds containing sulfur are formed together with the methanol. As this is a serious matter, the author suggests that used washes might be regenerated with wastes containing acetate instead of sulfate, so that the fibrous material would be heated with mixtures of hydrate and acetate instead of hydrate and sulfide. The practical process described by Hagglund for the use of his method, and so far satisfactory only on a small scale, involves continuous operation under pressure, with filtering, pumping, and preheating of the liquors, followed by decomposition in a reaction vessel under pressure with the separation of gases a t the top and the condensation of solid material on the sides. Pyrogenetic Treatment in Presence of Catalysts
Research on the pyrogenetic treatment of the wastes without pressure but in the presence of catalysts is going forward in the writer’s laboratories. Zinc and aluminum chlorides
F’ol. 19: s o . 3
have been tested, but the results obtained are not yet sufficiently confirmed to warrant announcement. Experiments will also be made with finely divided metals as catalysts. The electrolytic method for treating these wastes involve> the difficulty, when there are chlorides in the solution, of the action of chlorine or oxygen a t the anode on the organic substances and the separation of large quantities of gelatinous matter which are difficult to decant and still more difficult to filter. As a matter of fact, electrolysis resulting in a partial regeneration of the alkali has been carried out here with diaphragm cells having an iron cathode and a graphite anode. But i t would doubtless be cheaper to obtain such alkali in dilute form from electrolytic cells. Utilization of Wastes from Chlorine Process
As regards the direct utilization of waste liquors from the chlorine process, Professor Casaburi, of Naples, has already obtained interesting results on a semicommercial scale in the destruction of plant parasites and also in the tanning of hides. Such uses were reported by the author a t the meeting of the Associazione Italiana di Chimica in Sicily in the spring of 1926.
Our Expanding Trade in Perfumery and Toilet Articles‘ By Otto Wilson irL.SbBY
I
BUILDIXG, \VASHIKGTUN,
S T H E general industrial and trade expansion that
has marked the post-war period in the United State>, the industry which has to do with perfumery and toilet preparations of all kinds has more than held its own. The growth in the value of its output has indeed been remarkable. I n a little more than a decade this output has been multiplied six times over, and the gain in the last two years alone has matched the entire annual production before the war. This activity has served a demand very largely domestic. Our foreign trade in these articles has gone rapidlv forward, but the amount crossing the borders of the country every year is but a small proportion of the total produced. Analyzing the trade in a search for the causes of thib enormous expansion, we can easily see that they lie both inside and outside the industry itself. Articles of luxury as most of them are, perfumes and toilet preparations are consumed, in some measure, almost universally. Their sale is peculiarly responsive to any conditions which affect the spending power of the mass of the people. The business has thus been easily swept along on the tide of commercial activity that has ruled in recent years. The point has been well made, however, that this rapid growth has not been merely a passive response to a swelling demand, but as in a great many other lines of trade has been partly due to a marked development in the science of merchandising. Prosperous times have simply furnished the opportunity for the extension of credit and installment-plan buying, the opening up of new levels of consumption by advertising, etc., to which much of the expansion in this and other chemical industries is directly due. Peculiar to the perfumery and toilet-article industry are two causes of expansion which may be cited as especially prominent. One is the much greater addiction of girls and women to cosmetics of all kinds than before the war. One 1 Received
February 10, 1927.
D.
c.
of the \-agaries of fashion that has characterized the ao-called
“jazz” age, this turn in taste has had the serious economic results which always follow such whimsical changes, and has diverted tens of millions of dollars to the manufacturers who could satisfy it. The other factor is the rise of artificial and synthetic aromatic compounds. Kot only have these newcomers into the ranks of trade enlarged the market for perfumes by keeping prices down, but they have stimulated the production of the natural essences and have mixed with them to swell the volume necessary t o meet the new demand. The results of these factors are shown in the figures (from the Bureau of the Census) of total value of output of perfumery and toilet preparations in the United States for various years since the war as compared with 1914 (Table I). Table I-Total
ii
O u t p u t i n United States since t h e War Compared w i t h 1914 YEAR VALUE 1914 J 26,966,000 1919 82,084,000 1921 90,756,000 1923 119,237,000 1926 141,488,000a Preliminary.
This 500 per cent increase has come about almost entirely through the enlargement of the capacity of existing plants. The number of establishments engaged in the business is about the same as in pre-war days, some five hundred or six hundred. Production is strongly concentrated, however, less than 6 per cent of the total number turning out nearly two-thirds of the total finished goods. New York is by far the leading state, as it has been for many years, followed by Illinois, and the manufacture of toilet preparations continues to be confined almost wholly to eastern and midwestern states. Of the output of the industry in 1925, perfumery and toilet waters made up only about 15 per cent. Much more irn-
