GB1564373A - Process for the separation of dinitroanthraquinone mixtures - Google Patents
Process for the separation of dinitroanthraquinone mixtures Download PDFInfo
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Abstract
Dinitroanthraquinone mixtures which contain nitrobenzene are separated. The process comprises the following steps: a) 1 part by weight of a dinitroanthraiquinone mixture containing 4.5 to 9 parts by weight of nitrobenzene and/or the solution present after the separation of 1,5-dinitroanthraquinone as per step b) is treated at 100 - 200 DEG C and then the insolubles are separated off at 100 - 150 DEG C. b) The residue obtained according to a), which consists essentially of 1,5-dinitroanthraquinone, is treated with 1 to 4 parts by weight of nitrobenzene at 140 DEG C to the boiling temperature and then cooled down to 90 to 130 DEG C, and the undissolved 1,5-dinitroanthraquinone is separated off. c) Finally the solution remaining according to step a) after the insolubles have been separated off is cooled down to 90 to 120 DEG C and the crystallised 1,8-dinitroanthraquinone is separated off. The 1,5- and 1,8-dinitroanthraquinone obtained can be used for synthesising anthraquinone dyes.
Description
(54) PROCESS FOR THE SEPARATION OF
DINITROANTHRAQUINONE MIXTURES
(71) We, BAYER AKTIENGESELLSCHAFT, a body corporate organised under the laws of Germany, of Leverkusen, Germany, do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: In the dinitration of anthraquinone, mixtures are obtained, as is known, which essentially consist of 1,5-, 1,8-, 1,6- and 1 ,7-di- nitroanthraquinone. Various methods for the separation of such mixtures are described in the literature. With oleum, for example, the separation is carried out according to German Offenlegungsschrift (German Published
Specification) 2,143,253, with monohydrate (= 100% strength sulphuric acid) it is carried out according to Helv. chim. Acta 14, 1404 (1931), with N-methylpyrrolidone it is carried out according to German Offenlegungsschrift 2,334,713, with nitrobenzene it is carried out according to Japanese Laidopen Published Specification 49-76,851 and with nitrobenzene and/or nitrotoluene it is carried out according to German Offenlegungsschrift 2,248,704.
However, these processes are unsatisfactory with regard to the quality and/or the yield and are actually only suitable for the isolation of 1,5-dinitroanthraquinone. 1,5dinitroanthraquinone obtained by this separation process still containing, however, about 5% of 1,8-dinitroanthraquinone (compare, for example, German Offenlegungsschrift 2,248,704).
Such a content of 1 ,8-dinitroanthraquinone in the 1,5-dinitroanthraquinone is very troublesome, however, in the preparation of secondary products, for example of industrially important 1,5-diaminoanthraquinone and of l-amino-5-benzoyl- amino-anthraquinone. Thus, in the prepa
ration of 1 ,5-diamino-anthraquinone, the
1 ,8-dinitroanthraquinone is also reduced and is then present in the 1,5-diamino- anthraquinone as 1,8-diamino-anthraquin- one. During the monobenzoylation reaction, the 1,8-diamino-anthraquinone is converted into l-benzoylamino-8-aminoanthraquinone and 1 ,8-dibenzoylamino-anthra quinone and is present in this form in the 1 - amino - 5 - benzoylamino - anthraquinone. The removal of the undesired secondary products of 1,8 - dinitroanthraquinone can be effected only with difficulty and necessitates complicated and wasteful operations. If the 1,8 - isomeric by-products are not removed, these have a disadvantageous effect on yields and/or shades and/or fastness properties in the preparation of dyestuffs which are prepared from 1 - amino - 5 - benzoylamino anthraquinone. Thus as complete a separation as possible of the 1,8 - dinitroanthraquinone in the 1,5 - dinitroanthraquinone is of great industrial importance.
The separation proceses described above are completely unsuitable for the preparation of pure 1,8 - dinitroanthraquinone, which is also a valuable dyestuff intermediate product. Thus, for example, a 1,8 - dinitroanthraquinone which contains 15% of 1,5 - dinitroanthraquinone as an impurity is obtained by the process in German
Offenlegungschrift 2,248,704.
A process for the separation of dinitroanthraquinone mixtures using nitrobenzene has now been found, which comprises the steps of
a) treating 1 part by weight of a dinitroanthraquinone mixture with a total of 4.5 - 9 parts by weight of nitrobenzene, using either nitrobenzene alone, or together with the solution obtained after the separation of 1,5 - dinitroanthraquinone according to step b) and optionally wash liquid recycled from step b); or with the said solution from step b) together with part of the solution obtained from step d), at 100 to 2000C and then separating off the undissolved constituents at 100 to 150"C, the temperature of the treatment being the same or higher than the temperature of the separation during at least part of the treatment,
b) treating the residue, which is obtained according to step a) and essentially consists of 1,5 - dinitroanthraquinone, with 1 4 parts by weight of nitrobenzene at a temperature from 140"C to the boiling point, then cooling the mixture to 90 to 1300C and separating off and optionally washing with nitrobenzene the 1,5 - dinitroanthraquinone which is not dissolved,
c) cooling the solution obtained after the separation of the undissolved constituents according to step a) to 90 to 120"C and separating off and optionally washing with nitrobenzene the 1,8 - dinitroanthraquinone which has crystallised out,
d) in order to separate l,X-dinitroanthra- quinone (where X denotes the 5, 6, 7 or 8 ring position) the solution obtained after separation of the 1,8 - dinitroanthraquinone optionally combined with the washing liquid from the washing of 1,8 dinitroanthraquinone is cooled to 5 to 850C and the mitxure which crystallises out is separated off,
e) in order to separate X,Y - dinitroanthraquinone (where Y denotes the 1 or 2 and X denotes the 5, 6, 7 or 8 ring positions) the remaining solution from the 1,Xdinitroanthraquinone separation is distilled to dryness under reduced pressure.
The process of the present invention makes possible the isolation of 1,5-dinitroanthraquinone in purities of over 96% with a separation yield of over 80%. After separating off the 1,5 - dinitroanthraquinone, 1,8 - dinitroanthraquinone can be obtained in a similar purity to the 1,5dinitroanthraquinone. In general, the 1,5dinitroanthraquinone and 1,8 - dinitroanthraquinone isolated by the process according to the invention contain less than 2%, often less than 1%, of the other isomer. 1,5- and 1,8 - dinitroanthraquinone of such quality is certainly obtained when the products separated off according to steps b) and c) of the inventive process are washed with nitrobenzene. In cases where the separated products have a high content of solids (i.e. a low content of absorbed nitrobenzene), for example more than 70%, especially more than 80%, products of such purities can also be obtained often without washing with nitrobenzene.
A preferred embodiment of step a) of the inventive process comprises one or more of the following process features and can be carried out, for example, by treating 1 part by weight of a dinitroanthraquinone mitxure with 5.5 to 8 parts by weight of nitrobenzene at 110 to 200"C and then separating off the undissolved constituents at 110 to 1300C.
By a preferred heating to a temperature above the temperature at which the separation is carried out, preferably to a temperature above 160"C, one achieves a considerable coarsening of the undissolved portions and of those portions which have been precipitated during the cooling; because of this the separation period and the moisture remaining in the residue (= part of the mother-liquor) are greatly diminished.
After a period of 1/2 - 1 hour of stirring preferably at 110 to 1300C the crystallisation equilibrium is reached to an extent that these advantages are obtained upon separation. By the preferred heating to temperatures above the temperature at which the separation is carried out one achieves further a higher content of 1,5dinitroanthraquinone in the separated undissolved constituents and normally a higher purity of 1,5-dinitroanthraquinone separated in the following step b).
The residue obtained according to step a), which essentially consists of 1,5-dinitroanthraquinone, is treated with 2 to 3 parts by weight of nitrobenzene at a temperature of 150 to 200 C, preferably of 160 to 180 C, the mixture is then cooled to 100 to 1100 C and the 1,5 - dinitroanthraquinone which precipitates is separated off and optionally washed with 0.3 to 1 part by weight of nitrobenzene.
The solution obtained after separating off the undissolved constituents according to step a) is cooled to 90 to 1100 C, preferably to 100 to 110 C, and the 1,8 - dinitroanthraquinone which has crystallized out is separated off and optionally washed with 0.3 to 1 part by weight of nitrobenzene.
The solution obtained after the separation of the 1,8 - dinitroanthraquinone optionally combined with the washing liquid from the washing of 1,8 - dinitroanthraquinone is cooled to 5 to 850C, a 1,X - dinitroanthraquinone mixture (X = 5, 6, 7 and 8) separating out. The mixture is separated off and some of the remaining solution is used again for separating the starting dinitroanthraquinone mixture employed and some is concentrated by distillation to dryness in vacuo to separate the X,Y-dinitroanthraquinone (X = 5, 6, 7 and 8; Y = 1 or 2). It is possible to wash the separated 1,X-dinitroanthraquinone with nitrobenzene, however, this gives normally no special advantages because the desired qualities can be obtained without carrying out a washing. It is possible to separate out the 1,X-dinitroanthraquinone mixture from all of the solution obtained after the separation of the 1,8-dinitroanthraquinone or only from a part of this solution. It is possible to isolate sepa rately the remaining dinitroanthraquinone portions from this solution remaining after the separation of 1,8-dinitroanthraquinone and from the solution obtained after the separation of 1 ,X-dinitroanthraquinone by distilling off nitrobenzene. However, it is advantageous to work up both solutions jointly by distilling off nitrobenzene. Dependent on the amount of the solution remaining after the separation of 1,8-dinitroanthraquinone which is used for the isolation of 1 ,X-dinitroanthraquinone X,Y - dinitroanthraqiuone mixtures of different composition can be obtained. In this manner, further dinitroanthraquinones can also be obtained, such as 1,6-, 1,7-, 2,6- and 2,7-dinitroanthraquinone, in addition to the 1,5and 1,8-dinitroanthraquinone which remained. The temperature to which the solution remaining after the 1,8-dinitroanthraquinone separation, optionally together with the wash liquid from the washing of 1,8dinitroanthraquinone, is cooled is decisive for the composition of the 1 ,X-dinitroanthra- quinone mixture obtained. If, for example, the solution is cooled to a temperature which is above 60 - 70"C, a 1,5- and 1,8dinitroanthraquinone mixture is obtained which contains only about 2 to 5% of 1,6
and 1 ,7-dinitroanthraquinone, whilst at lower temperatures a dinitroanthraquinone mixture is isolated which can contain up to 40% of 1,6- and 1,7-dinitroanthraquinone.
In the residual solution, some of which, as mentioned above, can be used again for the separation of the dinitroanthraquinone mixture employed, there are the remaining nitroanthraquinone compounds which have not been separated off, mainly residual 1,5and 1 ,8-dinitroanthraquinone, in addition to the majority of the 1,6/1 ,7-dinitroanthraquinone contained in the material employed.
This X,Y-dinitroanthraquinone (X = 5, 6, 7 and 8; Y = 1 or 2) can be isolated by distilling off the nitrobenzene to dryness, preferably under reduced pressure.
When the nitrobenzene used is re-employed in the form of a part of the solution obtained after separating off 1 ,X-dinitro- anthraquinone for the dinitroanthraquinone separation, care must be taken that no more than 0.25 part by weight of dinitroanthraquinones, relative to 1 part by weight of the dinitroanthraquinone mixture employed, is recycled with the nitrobenzene. The separations mentioned above, which are separations of solids from liquids, can be carried out by applying customary methods, for example by filtration, decantation or in a hydrocyclone. The preferred measures and features stated above can be applied separately; for example the relative amounts of substances and temperatures given for a preferred separating operation can be varied independently from one another.
It is an essential characteristic of the present invention that the dinitroanthraquinone mixture employed is initially pretreated with nitrobenzene, preferably in the form of a solution obtained after carrying out step b) and/or after separating 1 ,X-di- nitroanthraquinone, whilst hot, and the resulting crude 1,5 - dinitroanthraquinone, which still contains about 6 to 30%, preferably 8 to 20%, of 1,8-dinitroanthraquinone, is again after-treated with pure nitrobenzene. The solution obtained after carrying out step b) can be used in total or partially, the solution obtained after separating 1 ,X-dinitroanthraquinone is preferably partially used for the separation of dinitroanthraquinone mixtures. Only by a double treatment with nitrobenzene, in which the starting dinitroanthraquinone mixture is also treated with the solution obtained after carrying out step b), is a 1,5-dinitroanthraquinone obtained in separation yields of over 80% and purities over 96%, with a 1,8dinitroanthraquinone proportion of less than 2%, often less than 1%.
Furthermore, it is important for the process according to the invention that in the separation of dinitroanthraquinone mixtures at least about 75%, but preferably about 80 to 86%, of the 1,5-dinitroanthraquinone present are separated off before the 1,8-dinitroanthraquinone crystallises out or that, relative to the 1,8-dinitroanthraquinone. only a maximum of 25%, preferably a maximum of 20%, of 1,5-dinitroanthraquinone is still present. The isolation of 1,8-dinitroanthraquinone which only still contains less than 2% of 1,5-dinitroanthraquinone is otherwise no longer possible or only possible in very low yields.
The recycling, which takes place by the process according to the invention, of the nitrobezene solutions obtained in the 1,5and 1,X-dinitroanthraquinone separation.
especially the recycling of the solution obtained from the fine purification of 1 ,5-di- nitroanthraquinone and also the recycling of solution obtained after the separation of 1 ,X-dinitroanthraquinone, into the dinitroanthraquinone separation effects a significant rise in the separation yield in the separation of 1,5- and 1,8 - dinitroanthraquinone,
Furthermore, these measures make it possible to carry out the process according to the invention particularly economically, since only a proportion of the amounts of solvent used must be purified by distillation.
The dinitroanthraquinone containing mixtures subjected to the separation process can contain some water, for example in form of a precipitate obtained in the dinitration process of anthraquinone after filtration and washing with water until neutral. Before subjecting such water containing mixtures to the separation process the water is to be removed, for example by azeotropic distillation at normal or reduced pressure. The small amount of nitrobenzene which distills off together with water is to be replaced by fresh nitrobenzene. Preferably the nitrobenzene obtained after cooling and phase separation of the azeotropic distillate is used for this purpose. It is also possible to subject dinitroanthraquinone containing mixtures to the separation process which contain up to 2% by weight of sulfuric acid without getting worse results with respect to quality and yield.
Virtually all dinitroanthraquinone mixtures accessible by industrial routes can be employed in the process according to the invention. Thus, for example, dinitroanthraquinone mixtures can be separated which are obtained by the nitration of anthraquinone in highly-concentrated nitric acid, by the nitration of anthraquinone using a mixture of highly-concentrated nitric acid and 0.75 to 2 parts by weight of sulphuric acid, relative to the weight of nitric acid, or by the nitration of anthraquinone in excess sulphuric acid, which optionally contains SO,, or hydrofluoric acid or organic solvents. It is also possible to employ those dinitration products which have been obtained by the nitration of 1nitroanthraquinone, which may contain other nitroanthraquinones as impurities.
The 1-nitroanthraquinone to be nitrated can contain anthraquinone, 2-nitroanthraquinone and the various dinitroanthraquinone isomers as impurities, especially if it has been obtained as the residual product in the purification of l-nitroanthraquinone by crystallisation or distillation.
Furthermore, those dinitroanthraquinone mixtures which are obtained by mixing any desired products, solutions or suspensions of any desired origin containing 1,5- and 1,8-dinitroanthraquinone can also be employed in the process according to the invention. The content of any 1,6- and 1,7dinitroanthraquinone which may be present and the raio of 1,5-dinitroanthraquinone to 1,8-dinitroanthraquinone are of minor importance.
The process according to the invention can be carried out both discontinuously and partly or entirely continuously. The 1,51,8-dinitroanthraquinone obtained according to the invention can be converted directly into the corresponding amino compound and then further processed to give anthraquinone dyestuffs (compare, for example, Friedlaender, Fortschritte der Teerfarben-Fabrikation (Advances in the Manufacture of Aniline Dyes), 22nd part (1935), page 1014; Fiat Final Report 1313, German Dyestuffs and Intermediates, II, page 26).
The Examples which follow are intended to illustrate further the process according to the invention. The analyses in the Examples are based on high pressure liquid chromatography and on semi-quantitative thin layer chromatography.
Examples 1. Separation of dinitroanthraquinone mixture having the composition: 0.5% of 2,6-dinitroanthraquinone, 0.4% of 2,7-dinitroanthraquinone, 1.8% of l-nitroanthraquinone, 9.8% of 1,6-dinitroanthraquinone, 9.6% of 1,7-dinitroanthraquinone, 39.9% of l,5-dinitroanthraquinone and 36.6% of 1 ,8-dinitroanthraquinone, obtained during the nitration of 208 g of anthraquinone with a mixture of 424 g of 98% strength nitric acid and 500 g of sulphuric acid monohydrate, the mixture having been stirred initially at 40"C (1 an hour), then at 50"C (+ an hour).
The instructions which follow refer to a crystallisation with recycling of the mother liquor after all the crystallisation equilibria are established. For starting up, pure nitrobenzene is used instead of recycled mother liquor.
1.1. Isolation of the 1 ,5-dinitroanthraquinone
65.0 g of the above dinitroanthraquinone mixture together with 252 g of recycled mother liquor from 1.3. and 252 g of recycled mother-liquor from the fine purification described below are warmed to 120"C for 0.5 hours, whilst stirring, and the mixture is then filtered at 1200 C. The filtrate is used for further processing to give 1,8-dinitroanthraquinone according to 1.2. The moist filter cake is warmed to 1600C with 180 g of nitrobenzene for 0.5 hour, whilst stirring. The mixture is then cooled to 100"C in the course of 0.25 hour, and after stirring for 0.5 hour at 100"C, is filtered. The residue is washed with 60g of nitrobenzene, heated to 100"C, in portions. The combined filtrates of the fine purification which still contain dissolved dinitroanthraquinone and/or mononitroanthraquinone are used for the next 1,5dinitroanthraquinone crystallisation. After drying the residue in vacuo at 1000C, there are obtained: 22.4 g of 1,5-dinitroanthraquinone (97.3% of 1,5-dinitroanthraquinone, 1.1 % of 1 ,8-dinitroanthraquinone, 0.2% of 1 ,6-dinitroanthraquinone and 0.1% of 1 ,7-dinitroanthraquinone).
Separation yield 84.1%.
1.2. Isolation of the 1,8-dinitroanthraquinone
The filtrate from the 1,5-dinitroanthraquinone separation (about 510 g) is cooled to 1050 C, after it has been warmed, if appropriate, to 140"C in order to achieve a clear solution, and seeded with a few crystals of 1,8-dinitroanthraquinone and the mixture is stirred for 2 hours at 1050C.
It is filtered and the residue is washed with 48 g of cold nitrobenzene and dried in vacuo at 100"C: 7.3 g of 1,8-dinitro anthraquinone (98.5% of 1,8-dinitroanthraquinone and 0.6% of 1,5-dinitroanthraquinone).
Separation yield 30.2%.
The combined filtrates are used for the separation of the 1 ,X-dinitroanthraquinone mixture according to 1.3.
1.3. Isolation of the 1,X-dinitroanthraquinone (X = 5, 6, 7 and 8)
The combined filtrates from the 1 ,8-di- nitroanthraquinone separation (about 540 g) are warmed to 120"C until the solution becomes clear. It is then cooled to 25"C and stirred at this temperature for 3 hours.
The product which has crystallised out is then filtered off and dried in vacuo at 1000C: 21.0 g of 1,X-dinitroanthraquinone (6.7% of 1 ,6-dinitroanthraquinone, 15.6% of 1,7-dinitroanthraquinone, 10.8% of 1,5dinitroanthraquinone and 60.7% of 1,8dinitroanthraquinone and 2.2% of l-nitroanthraquinone).
1.4. Isolation of the X,Y-dinitroanthraquinone (Y = 1 and 2, X = 5, 6, 7 and 8)
The filtrate from 1.3. (about 504 g) is divided, about 252 g being recycled to 1.1 for the next crystallisation. The remainder is distilled to dryness in vacuo: 11.1 g of
X,Y-dinitroanthraquinone (2.0% of 2,6-dinitroanthraquinone, 1.9% of 2,7-dinitroanthraquinone, 37.5% of 1,6-dinitroanthraquinone, 22.1% of 1,7 - dinitroanthraquinone, 6.1% of 1,5-dinitroanthraquinone and 14.4% of 1 ,8-dinitroanthraquinone and 3,6% of l-nitroanthraquinone).
The nitrobenzene which has distilled off
is used again in 1.1. and 1.2.
2. Separation of a dinitroanthraquinone mixture having the composition of Example 1 (for establishing the crystallisation equilibria, compare Example 1).
2.1, Isolation of the 1,5-dinitroanthraquinone
65.0 g of the dinitroanthraquinone mixture having the composition as in Example
1, together with 216 g of nitrobenzene and 252 g of recycled filtrate and washing liquid from the fine purification described below, are warmed to 1200C for 0.5 hour, whilst stirring, and the mixture is then filtered at 120 C. The filtrate is used for the further processing to give 1,8-dinitro
anthraquinone according to 2.2. The moist
residue is warmed to 1800C with 180 g
of nitrobenzene for 0.5 hour, whilst stirring.
The mixture is then cooled to 1000C in
the course of 0.25 hour and, after stirring
for 0.5 hour at 1000 C, the product which
has crystallised out is filtered off. The
material on the filter is washed with 60 g
of hot nitrobenzene in portions. The com
bined filtrates of this fine purification are used for the next 1,5-dinitroanthraquinone crystallisation. After drying the residue in vacua at 100"C, there arse obtained: 21.7 g of 1,5-dinitroanthraquinone (98.8% of 1 ,5-dinitroanthraquinone and 1.1 % of 1,8dinitronanthraquinone).
Separation yield 82.7%.
2.2. Isolation of the 1,8-dinitroanthraquinone
The filtrate from 2.1. is cooled to 1000C and stirred at 100"C for 2 hours. The crystals are filtered off( washed with 48 g of nitrobenzene and dried in vacuo at 100 C: 6.8 g of 1,8-dinitroanthraquinone (97.5% of 1,8-dinitroanthraquinone and 0.7% of 1 ,5-dinitroanthraquinone).
Separation yield 27.9%.
2.3. Isolation of the 1,X-dinitroanthraquinone (X = 5, 6, 7 and 8)
The combined filtrates from the 1,8-dinitroanthraquinone separation are cooled to 250 C and stirred for 3 hours at this temperature. The precipitate is then filtered off and dried at 100"C in vacuo: 16.1 g of 1 ,X-dinitroanthraquinone (2.6% of 1,6dinitroanthraquinone, 4.9% of 1,7-dinitroanthraquinone, 12.6% of 1,5-dinitroanthraquinone and 74.4% of 1,8-dinitroanthraquinone).
2.4. Isolation of the X,Y-dinitroanthraquinone (Y = 1 and 2, X = 5, 6, 7 and 8)
The filtrate from 2.3. is distilled to dryness in vacuo: 19.5 g of X,Y-dinitroanthraquinone (1.5% of 2,6-dinitroanthraquinone, 1.5% of 2,7-dinitroanthraquinone, 30.8% of 1 ,6-dinitroanthraquinone, 28.2% of 1,7-dinitroanthraquinone, 7.8% of 1,5-dinitroanthraquinone and 16.1% of 1,8-dinitroquinone and 4.2% of l-nitroanthraquinone).
The nitrobenzene which has distilled off can be used again in 2.1. and 2.2.
3. Separation of a dinitroanthraquinone mixture having the composition: 0.4% of 2,6-dinitroanthraquinone, 0.5% of 2.7-dinitroanthraquinone, 1.7% of l-nitroanthraquinone, 10.6% of 1,6-dinitroanthraquinone, 10.8% of 1,7-dinitroanthraquinone, 36.5% of 1,5-dinitroanthra quinine, 34.7% of 1,8-dinitroanthraquinone and 0.1% of anthraquinone, obtained during the nitration of 188 g of anthraquinone, 145 g of a mother liquor product of a 1-nitroanthraquinone prepurification and 87 g of a distillation residue from a l-nitroanthraquinone distillation (composition of the mixture: of anthraquinone, 5.5% of 1,5-dinitroanthraquinone, 5.1% of 1,8-dinitroanthraquinone, 1.5% of 1,7-dinitroanthraquinone and 1,4% of 1,6-dinitroanthraquinone, 26.7% of 1 -nitroanthraquinone and 9.1% of 2-nitroanthraquinone) with 627 g of 98% strength nitric acid and 702 g of 96%
strength sulphuric acid at a temperature of 40"C (+ an hour), which was then raised to 500C (+ an hour) and 60"C (+ an hour).
The instructions which follow refer to a crystallisation with nitrobenzene recycling after all the equilibria are established. For starting up, pure nitrobenzene is used instead of recycled mother liquor.
3.1. Isolation of the 1,5-dinitroanthraquinone
70.7g of the above dinitroanthraquinone mixture together with 252 g of recycled filtrate and wash liquid from the fine purification of 1,5-dinitroanthraquinone described further below, 72 g of pure nitrobenzene and 180 g of recycled filtrate from 3.3 are warmed to 1200C for 1 hour, whilst stirring, and the mixture is then filtered at 120"C. The filtrate is used for the further processing to give 1,8-dinitroanthraquinone according to 3.2. The moist filter cake is warmed to 1800C with 180 g of nitrobenzene for 0.5 hour, whilst stirring, the mixture is then cooled to 100"C and filtered after stirring for i an hour at 100"C and the residue is washed with 60 g of nitrobenzene, heated to 1000C, in portions, and dried at 100"C. There are obtained: 22.9 g of 1,5-dinitroanthraquinone (97.8% of 1,5-dinitroanthraquinone, 1.8% of 1,8-dinitroanthraquinone and 0.3 % of l-nitroanthraquinone).
Separation yield 86.8%.
3.2. Isolation of the 1,8-dinitroanthraquinone
In this process, in the manner described in Example 1.2., the filtrate from 3.1 is crystallised at 100-102"C and the crystals are then worked up: 9.5 g of 1,8-dinitroanthraquinone (97.8% of 1,8-dinitroanthraquinone and 0.3% of 1,5-dinitroanthraquinone).
Separation yield 38%.
The combined filtrates are used for the separation, according to 3.3., of a 1,Xdinitroanthraquinone mixture.
3.3. Isolation of the 1,X-dinitroanthraquinone (X = 5, 6, 7 and 8)
The combined filtrates from the 1,8-dinitroanthraquinone separation in 3.2. are stirred at 60"C for 3 hours, after they had been brought into solution again by warming briefly to 1300 C. The precipitate is then filtered off and dried at 100"C: 13.2 g of 1,X-dinitroanthraquinone (1.5% of 1-nitroanthraquinone, 2.1% of 1,6-dinitroanthraquinone, 4.0% of 1,7-dinitroanthraquinone, 16.9% of 1,5-dinitroanthraquinone and 73.3% of 1,8-dinitroanthraquinone).
3.4. Isolation of the X,Y-dinitroanthraquinone (Y = 1 and 2, X = 5, 6, 7 and 8)
After separating off 180 g for recycling to 3.1., the filtrate from 3.3. is distilled to dryness.
21.9 g of X,Y-dinitroanthraquinone (3.8% of l-nitroanthraquinone, 1.2% of 2,6-dinitroanthraquinone, 1.3% of 2,7-dinitroanthraquinone, - 30.7% of 1,6-dinitroanthraquinone, 26.2% of 1,7-dinitroanthraquinone, 5.5% of 1,5-dinitroanthraquinone and 21.2% of 1,8-dinitroan crystallised at 95"C in the course of 6 hours and then worked up: 11.7 g of 1,8dinitroanthraquinone (98.0% of 1,8- and 1,3 % of 1 ,5-dinitroanthraquinone).
Separation yield 46.9%.
The combined filtrates are used for the separation, according to 4.3., of a 1,X-dinitroanthraquinone mixture.
4.3. Isolation of the 1,X-dinitroanthraffquinone (X = 5, 6, 7 and 8)
The combined filtrates from the 1,8-dinitroanthraquinone separation in 4.2 are stirred at 250C for 5 hours after they had been brought into solution again by briefly warming to 1300C. The precipitate is then filtered off and dried at 100"C: 21.0 g of I ,X-dinitroanthraquinone (1.8% of 1nitroanthraquinone, 11.9% of 1,6-dinitroanthraquinone, 22.8% of 1 ,7-dinitroanthraqinone, 13.1% of 1,3-dinitroanthraquinone and 47.7% of 1 ,8-dinitroanthraquinone).
About half of the filtrate (about 256 g) is recycled to 4.1.
4.4. Isolation of the X,Y-dinitroanthraquinone (Y = 1 and 2, X = 5, 6, 7 and 8)
The remaining filtrate from 4.3 is distilled to dryness in vacuo at 1500C: 12.5 g of X,Y-dinitroanthraquinone (2.7% of 1-nitroanthraquinone, 1.8% of 2,6-dinitroanthraquinone, 1.7% of 2,7-dinitroanthraquinone, 36.7% of 1,6-dinitroanthraquinone, 19.0% of 1,7-dinitroanthraquinone, 6.2% of 1,5-dinitroanthraquinone and 15.1% of 1,8-dinitroanthraquinone).
5. Separation of a dinitroanthraquinone mixture having the composition: 0.4% of 2,6-dinitroanthraquinone, 0.4% of 2,7-dinitroanthraquinone, 1.7% of l-nitroanthraquinone, 10.6% of 1,6-dinitroanthraquinone, 10.8% of 1,7-dinitroanthraquinone, 36.5% of 1,5-dinitroanthraquinone, 34.7% of 1,8-dinitroanthraquinone and 0.10% of anthraquinone, obtained according to the nitrataion instructions given in Example 3.
The instructions which follow refer to a crystallisation with filtrate recycling after all the equilibria are established. For statring up, pure nitrobenzene is used instead of recycled filtrate.
5.1. Isolation of the 1,5-dinitroanthraquinone 70.7 g of the above dinitroanthraquinone mixture together with 260 g of recycled filtrate from the fine purification of the 1,5-dinitroanthraquinone described further below and 73 g of recycled filtrate from 5.3. are warmed to 1700C for 1 hour, cooled to 1200C, stirred for 1 hour 1200C and the mitxure is then filterer at 1200C.
The filtrate is used for the further processing to give 1,8-dinitroanthraquinone according to 5.2. The moist filtrate cake is warmed to 1600C with 180 g of nitrobenzene for 0.5 hour, whilst stirring, the mixture is then cooled to 100"C and, after stirring at 1000 C for 1/2 an hour, the precipitate is sharply sucked off, and dried at 100"C. There are obtained: 22.5 g of 1,5dinitroanthraquinone (97.6% of 1 ,5-di- nitroanthraquinone, 0.8% of 1,8-dinitroanthraquinone and 0.3% of l-nitroanthraquinone.
Separation yield 85.1 %.
5.2. Isolation of the 1,8-dinitroanthraquinone
The filtrate from the 1,5-dinitroanthraquinone separation is warmed to 140"C with 183 g of recycled filtrate from 5.3., whilst stirring, until a clear solution is obtained and the solution is then cooled to 100"C and allowed to crystallise out in the course of 1.5 hours. The crystals are filtered off, sharply sucked and dried at 1200C: 9.0 g of 1,8-dinitroanthraquinone (98.2% pure, containing 1.0% of 1,5-dinitroanthraquinone, 0.3 /O of 1,6-dinitroanthraquinone and 0.3% of 1,7-dinitroanthraquinone).
Separation yield 36.1%.
The combined filtrates are used for the separation, according to 5.3., of the 1,Xdinitroanthraquinone mixture.
5.3. Isolation of the ;1,X-dinitroanthra- quinone (X = 5, 6, 7 and 8)
The filtrates from 5.2. are cooled to 100C and stirred at this temperature for 3 hours.
The precipitate is then filtered off and dried in vacuo: 28.6 g of 1,X-dinitroanthraquinone containing 1 ,8-dinitroanthraquinone as the main component (50-60%) and 5-10% of 1 ,5-dinitroanthraquinone, 20-25% of 1 ,7-dinitroanthraquinone and about 15% of 1 ,6-dinitroanthraquinone.
About half of the filtrate is recycled to 5.1 and 5.2.
6. 1,5- and 1,8-dinitroanthraquinone can be obtained in very similar qualities and with very similar separation yields, if Example 4 is repeated, however using instead of 70.7 g dinitroanthraquinone of the given composition a) 76 g of a dinitroanthraquinone mixture of following composition: 0.7% 2,6-; 0.7% 2,7-; 12.9% 1,6-; 12.6% 1.7-; 35.3% 1.5-; 32.6% 1,8-dinitroanthraquinone and 1.4% l-nitroanthraquinone.
Such a dinitroanthraquinone mixture can be obtained as follows: A mixture containing 7% anthraquinone, 9.8% 1,5-, 9.2% 1,8-, 2.7% 1,6-, 2.7% 1,7-dinitroanthraquinone, 48.4% 1- and 16.4% 2-nitro- anthraquinone is nitrated with a mixed acid consisting of the 1.23 fold amount by weight of 98% nitric acid and the 1.4 fold amount by weight of 96% sulphuric acid at 40, 50 and 60"C (each temperature is maintained for 30 minutes). After dilution with water the nitration product is isolated in customary manner. The starting material for such nitration can be obtained by mixing the product obtained in the working up of the mother liquor of the purification of l-nitroanthraquinone by crystallisation and the product obtained as residue in the distillation of l-nitroanthraquinone.
b) 61.2 g of a dinitroanthraquinone mixture of following composition: 2% 1nitroanthraquinone, 3.4% 1.6-, 3.5% 1.7-, 47.2% 1,5- and 39.1% 1,8-dinitroanthraquinone.
Such a dinitroanthraquinone mixture can be obtained as follows: A mixture containing 20.5% 1,5-, 13.9% 1,8-, 0.5% 1,6-, 0.4% 1,7-dinitroanthraquinone, 59.8% 1and 0.1% 2-nitroanthraquinone is nitrated with a mixed acid consisting of the 1.4 fold amount by weight of 98% nitric acid and of the 1.67 fold amount by weight of 96% sulfuric acid at 40, 50 and 60"C (each temperature is maintained for 30 minutes). After dilution with water the nitration product is isolated in customary manner. The starting material for such nitration can be obtained as a residue in the distillation of l-nitroanthraquinone.
c) 8.15 g of a dinitroanthraquinone mix
ture of following composition: 1.0% 1
nitroanthraquinone, 1.3% 2,7-, 1.1 % 2,6-, 18.4% 1,6-, 17.9% 1,7-, 27.9% 1,5- and 28.7 O,; 1,8-dinitroanthraquinone.
Such a dinitroanthraquinone mixture can be obtained as follows: A mixture containing 11.2% anthraquinone, 3.4% 1,5-, 6.4% 1,8-, 4% 1,6-, 4% 1,7-dinitroanthraquinone, 41.4% 1- and 26.2% 2nitroanthraquinone is nitrated with a mixed acid consisting of the 1.4 fold amount by weight of 98% nitric acid and the 1.67 fold amount by weight of 96% sulfuric acid at 40, 50 and 60"C (each temperature is maintained for 30 minutes). After dilution with water the nitration product is isolated in customary manner. The starting material for such nitration can be obtained in the working up of the mother liquor of the pre-purification of l-nitroanthraquinone by crystallisation.
7. Separation of a dinitroanthraquinone mixture having the composition: 0.4% of 2,6-dinitroanthraquinone, 0.4% of 2,7-dinitroanthraquinone, 1.7% of l-nitroanthraquinone, 10.6% of 1,6-dinitroanthraquinone, 10.8% of 1,7-dinitroanthraquinone, 36.3% of 1 ,5-dinitroanthraquinone, 34,7% of 1,8-dinitroanthraquinone and 0.10% of anthraquinone, obtained according to the nitration instructions given in Example 3.
The instructions which follow refer to a crystallisation with recycling of mother liquor after all the equilibria are established. For starting up, pure nitrobenzene is used instead of recycled mother-liquor.
7.1 Isolation of the 1 ,5-dinitroanthraquinone
70.7 g of the above dinitroanthraquinone mixture together with 247 g of recycled mother-liquor from the fine purification of the 1,5 - dinitroanthraquinone described further below and all of the mother-liquor from 7.3. are warmed to 1800C for 3 hours, whilst stirring, then cooled to 1200C during 30 minutes by means of vaporiza- tion cooling of nitrobenzene at reduced pressure, then stirred for 1 hour at 1200C.
The mixture is then filtered at 1200C. The filtrate is used for the further processing to give 1,8-dinitroanthraquinone according to 7.2. The moist filter cake is warmed to 160"C with 180 g of nitrobenzene for 0.5 hour, whilst stirring, the mixture is then cooled to 100"C and, after stirring at 100"C for 1/2 an hour, the precipitate is filtered off, washed with 60 g of cold nitrobenzene in portions, and dried at 100"C. There are obtained: 22.4 g of 1,5dinitroanthraquinone (98.9% of 1,5-dinitroanthraquinone, 0.6% of 1,8-dinitroanthra
quinone and 0.1% of l-nitroanthraquinone).
Separation yield 85.9%
7.2 Isolation of the 1,8-dinitroanthraquinone
The filtrate from the 1,5-dinitroanthraquinone separation is warmed to 1400 C whilst stirring, until a clear solution is obtained and the solution is then cooled to 100"C and allowed to crystallise out in the course of 1.5 hours. The crystals are filtered off, washed with 48 g of cold nitrobenzene and dried at 1200C: 8.3 g of 1,8dinitroanthraquinone (97.4% pure, containing 0.8% of 1 ,5-dinitroanthraquinone, 0.4% of 1 ,6-dinitroanthraquinone and 0.5% of 1,7-dinitroanthraquinone).
Separation yield 82.9%.
A part of the combined filtrates are used for the separation, according to 7.3., of the 1 ,X-dinitroanthraquinone mixture.
7.3. Isolation of the 1,X-dinitroanthraquinone (X = 5, 6, 7 and 8)
Half of the filtrates from 7.3 (about 200 g) are cooled to 60"C and stirred at this temperature for 3 hours. The precipitate is then filtered off and dried in vacuo:
9.5 g of 1,X-dinitroanthraquinone containing 64.6% of 1,8-dinitroanthraquinone
and 13.5% of 1 ,5-dinitroanthraquinone,
13.0% of 1,7-dinitroanthraquinone and about 4.1% of 1 ,6-dinitroanthraquinone.
7.4 Isolation of X,Y-dinitroanthraquinone (X 1 and 2, Y = 5, 6, 7 and 8).
Half of the filtrate from 7.2 is freed of nitrobenzene in vacuo: 30.0 g X,Y-dinitroanthraquinone containing 30.9% of 1,8-, 8.3% of 1,5-, 21.2% of 1,7-, 24.4% of 1,6-, 1% 2,6-, 1% 2,7-dinitroanthraquinone and 2.7% l-nitroanthraquinone.
Claims (14)
1. A process for the separation of dinitroanthraquinone mixtures using nitrobenzene, comprising the steps of
a) treating 1 part by weight of a dinitroanthraquinone mixture with a total of 4.59 parts by weight of nitrobenzene, using either nitrobenzene alone, or together with the solution obtained after the separation of 1,5-dinitroanthraquinone according to step b) and optionally wash liquid recycled from step b); or with the said solution from step b) together with part of the solution obtained from step d), at 100 to 2000C and then separating off the undissolved constituents at 100 to 150"C, the temperature of the treatment being the same or higher than the temperature of the separation during at least part of the treatment,
b) treating the residue, which is obtained according to step a) and essentially consists of 1 ,5-dinitroanthraquinone, with 14 parts by weight of nitrobenzene at a temperature from 140"C to the boiling point, then cooling the mixture to 90 to 130"C and separating off and optionally washing with nitrobenzene the 1 ,5-dinitro- anthraquinone which is not dissolved,
c) cooling the solution obtained after the separation of the undissolved constituents according to step a) to 90 to 1200 C and separating off and optionally washing with nitrobenzene the 1,8-dinitroanthraquinone which has crystallised out,
d) in order to separate 1,X-dinitroanthraquinone (where X denotes the 5, 6, 7 or 8 ring position) the solution obtained after separation of the 1,8-dinitroanthraquinone optionally combined with the washing liquid from the washing of 1,8dinitroanthraquinone is cooled to 5 to 85"C and the mixture which crystallises out is separated off,
e) in order to separate X,Y-dinitroanthraquinone (where Y denotes the 1 or 2 and X denotes the 5, 6, 7 or 8 ring positions) the remaining solution from the 1 ,X-dinitroanthraquinone separation is distilled to dryness under reduced pressure.
2. A process according to claim 1 in which in step a) 1 part by weight of a dinitroanthraquinone mixture is treated with 5.5 to 8 parts by weight of nitrobenzene.
3. A process according to Claim 1 or 2, in which in step a) the separation of undissolved constituents is carried out at a temperature of 110 to 1300C.
4. A process according to any of the foregoing claims in which in step b) the residue obtained according to step a) is treated with 2 to 3 parts by weight of nitrobenzene.
5. A process according to any of the foregoing claims, in which in step b) the process is carried out at a temperature of 150 to 200"C.
6. A process according to any of the foregoing claims, in which in step b) and/ or in step c) the mixture is cooled to 100 to 1100C.
7. A process according to any of the foregoing claims, in which in steps b) and c) the 1,5-dinitroanthraquinone (b) and 1,8-dinitroanthraquinone (c) which have been separated off are washed with 0.3 to 1 part by weight of nitrobenzene.
7. A process according to any of the foregoing claims, in which in step a) the dinitroanthraquinone is treated with a mixture of nitrobenzene and a part of the solution obtained after carrying out step b).
8. A process according to any of
Claims 1 to 7, in which the solution obtained after carrying out step b) is used in total or partially and the solution obtained after separating 1 ,X-dinitroanthra- quinone is partially used for the separation of dinitroanthraquinone mixtures in step a).
9. A process according to Claim 1, when carried out substantially as described in any one of the Examples.
10. 1,5-dinitroanthraquinone when produced by the process of any of the foregoing claims.
11. 1,8-dinitroanthraquinone when produced by the process of any of the foregoing claims.
12. A process according to Claim 1, in which the treatment of dinitroanthraquinone and the separation off of the undissolved constituents are at the same temperature of 100 to 1500C and the separation in each of steps a), b), c) and d) is by filtration.
13. 1,5-dinitroanthraquinone when produced by the process of Claim 12.
14. 1,8-dinitroanthraquinone when produced by the process of Claim 12.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19762637733 DE2637733C3 (en) | 1976-08-21 | 1976-08-21 | Process for the separation of dinitroanthraquinone mixtures |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| GB1564373A true GB1564373A (en) | 1980-04-10 |
Family
ID=5986033
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB3451777A Expired GB1564373A (en) | 1976-08-21 | 1977-08-17 | Process for the separation of dinitroanthraquinone mixtures |
Country Status (9)
| Country | Link |
|---|---|
| JP (1) | JPS5325549A (en) |
| AT (1) | AT350542B (en) |
| BE (1) | BE857926A (en) |
| CA (1) | CA1111032A (en) |
| CH (1) | CH634038A5 (en) |
| DE (1) | DE2637733C3 (en) |
| FR (1) | FR2362111A1 (en) |
| GB (1) | GB1564373A (en) |
| IT (1) | IT1079921B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102056475A (en) * | 2008-06-04 | 2011-05-11 | 阿德里安·约翰尼斯·斯塔夫伦 | Spade |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2458536A2 (en) * | 1978-07-27 | 1981-01-02 | Ugine Kuhlmann | Purificn. of mixed di:nitro anthraquinone(s) - to obtain 1,5 and 1,8 isomers, by treating with specified acetic acid ester(s) |
| FR2432014A1 (en) * | 1978-07-27 | 1980-02-22 | Ugine Kuhlmann | PROCESS FOR OBTAINING HIGH PURITY A, A'-DINITRO-ANTHRAQUINONES |
| DE2854427A1 (en) * | 1978-12-16 | 1980-06-26 | Bayer Ag | METHOD AND APPARATUS FOR THE RECOVERY OF DRY 1,5- AND / OR 1,8- DINITROANTHRAQUINONE FROM SUSPENSIONS CONTAINING SOLID 1,5- AND / OR 1,8-DINITROANTHRAQUINONE AND LIQUID NITROBENZENE |
| DE3329453A1 (en) * | 1983-08-16 | 1985-03-07 | Bayer Ag, 5090 Leverkusen | METHOD FOR PRODUCING PURE 1-NITROANTHRACHINONE |
| JPH0811251B2 (en) * | 1984-08-18 | 1996-02-07 | 愛知製鋼株式会社 | Overload prevention device in cold roll forming |
| US20170350621A1 (en) * | 2016-06-06 | 2017-12-07 | Frontline Aerospace, Inc | Secondary solar concentrator |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE167699C (en) * | ||||
| BE789702A (en) * | 1971-10-07 | 1973-02-01 | Sumitomo Chemical Co | PROCESS FOR THE PREPARATION OF DINITROANTHRAQUINONS |
| JPS4976851A (en) * | 1972-12-05 | 1974-07-24 | ||
| JPS511709A (en) * | 1974-06-25 | 1976-01-08 | Mitsubishi Heavy Ind Ltd | Renzokusokoshijono itotooshihoho |
| DE2524747C3 (en) * | 1975-06-04 | 1980-12-18 | Basf Ag, 6700 Ludwigshafen | Process for the isolation of 1,5- / 1,8-dinitroanthraquinone with a high content of a, a '-duutro compounds |
-
1976
- 1976-08-21 DE DE19762637733 patent/DE2637733C3/en not_active Expired
-
1977
- 1977-08-16 CH CH1002877A patent/CH634038A5/en not_active IP Right Cessation
- 1977-08-17 GB GB3451777A patent/GB1564373A/en not_active Expired
- 1977-08-19 CA CA285,064A patent/CA1111032A/en not_active Expired
- 1977-08-19 AT AT603577A patent/AT350542B/en not_active IP Right Cessation
- 1977-08-19 IT IT5072077A patent/IT1079921B/en active
- 1977-08-19 JP JP9879977A patent/JPS5325549A/en active Granted
- 1977-08-19 FR FR7725463A patent/FR2362111A1/en active Granted
- 1977-08-19 BE BE2056176A patent/BE857926A/en unknown
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102056475A (en) * | 2008-06-04 | 2011-05-11 | 阿德里安·约翰尼斯·斯塔夫伦 | Spade |
Also Published As
| Publication number | Publication date |
|---|---|
| CH634038A5 (en) | 1983-01-14 |
| AT350542B (en) | 1979-06-11 |
| DE2637733C3 (en) | 1982-05-06 |
| ATA603577A (en) | 1978-11-15 |
| FR2362111A1 (en) | 1978-03-17 |
| CA1111032A (en) | 1981-10-20 |
| FR2362111B1 (en) | 1981-09-04 |
| DE2637733A1 (en) | 1978-02-23 |
| BE857926A (en) | 1978-02-20 |
| JPS5546382B2 (en) | 1980-11-22 |
| DE2637733B2 (en) | 1981-07-30 |
| JPS5325549A (en) | 1978-03-09 |
| IT1079921B (en) | 1985-05-13 |
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