JPS647053B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for deodorizing crude isopropyl alcohol. More specifically, the present invention includes nickel,
a metal selected from the group consisting of cobalt, iron, palladium, rhodium, ruthenium, platinum, tungsten and copper and not containing Raney metal types and oxides of these metals which are at least partially reduced; The present invention relates to a method for deodorizing crude isopropyl alcohol, which comprises contacting a deodorizing contact agent prepared by the above method with crude isopropyl alcohol in a fixed bed contacting method. In a preferred embodiment of the invention, the deodorizing contact agent has a minimum particle size greater than about 0.254 mm so as to be suitable for use in a fixed bed contact process, and less than about 1500 m ² /g. nickel supported on a carrier with a small surface area;
Crude isopropyl alcohol is deodorized using a deodorizing contact agent consisting of a group metal such as iron, cobalt, etc. The present invention uses such a deodorization process in combination with an extractive distillation process to extract high grade, e.g.
% and/or anhydrous grades of isopropyl alcohol. Manufacturing and sales of isopropyl alcohol
Currently manufactured commercial products are hampered by highly undesirable odors. These undesirable odors are known to be particularly strong and make the commercialization of these products, which currently have a wide variety of commercial uses, quite difficult. especially,
Their commercial uses include use as solvents, disinfectants, spray products, and among the many applications in which the presence of such odors is particularly important are cosmetic and pharmaceutical formulations among others. This problem is particularly important with respect to the commercial production of isopropyl alcohol, which has become widely used in fields such as cosmetics, disinfectants, etc. due to its excellent solubility, low toxicity and cost. Thus,
There is a considerable need for commercial methods for deodorizing products without unnecessarily interfering with the commercial production of such products. Generally, extractive distillation,
Use of ion exchange resin, activated carbon, activated alumina,
Efforts have focused on methods such as adsorption onto compounds such as sand. In many of these cases, patent owners have taken it upon themselves to analyze the various possible causes of the bad odor characteristics of these substances, such as in U.S. Pat. No. 2,729,682, which is assigned to the assignee of the present invention. I planned it. In the above patent, the patentee attempts to solve the "recycle" odor problem by adding _C4 - _C6 monoolefins into the propylene stream followed by water extractive distillation. US Pat. No. 2,857,436 describes a method for improving odor by sequentially passing a lower alcohol through a bed of unglazed porcelain and a bed of ferrous metal such as steel wool. These prior art methods are:
None have been commercially useful and economically attractive methods of obtaining products with acceptable odor levels. US Pat. No. 2,356,689 describes a process for purifying alcohols using specified amounts of solid cuprous chloride to stabilize and improve the odor of such alcohols. This method is concerned with the removal of certain small amounts of odors due to impurities. This method also
Cuprous chloride is used as part of the alcohol finishing or refining process. U.S. Pat. No. 2,663,745 describes a method for improving the quality of various alcohols by bringing them into intimate contact with small glass particles having a particle size of about 4 to 20 mesh. U.S. Patent No. 2,585,816 discloses that
The color of _C4 - _C12 alcohols made from _C3 - _C11 olefins can be changed by essentially reducing the sulfur content, e.g.
The use of various metals such as mercury, copper and nickel for the purpose of improving by reducing from 83 ppm to e.g. 10-27 ppm has been described. In a more recent development, Japanese Patent Publication No. 51-1684 describes another process for purifying isopropyl alcohol which consists of contacting isopropyl alcohol with various Raney metals, including Raney nickel. The method preferably consists of contacting the Raney metal in the presence of a reducing gas such as hydrogen. Ranney metal is approximately
Present in an amount of 0.01 to 5 parts. However, this process cannot be carried out commercially, especially because Raney metals are highly unstable and potentially dangerous to use. Therefore, in a commercially acceptable and simple manner,
Research continues into new methods for deodorizing lower alcohols, _C2 and _C3 alcohols such as isopropyl alcohol and their ether and ester derivatives such as diethyl ether. The present inventors have now developed crude isopropyl alcohol, which is composed of metal and/or at least partially reduced metal oxides, and is of suitable size, e.g., for use effectively in solid bed contact processes.
A simple, economical, and flexible method for reducing crude isopropyl alcohol to very high concentrations by contacting it with a deodorizing contact mass having a particle size greater than about 1/100th of an inch (25.4 mm). We discovered that it is possible to deodorize to a certain extent. That is, these particle sizes allow the deodorizing contact agent to be used in the column and provide sufficient support for the contact agent itself in the column to be useful in the fixed bed contacting process described above. Therefore, the deodorizing contact agent should be approximately 0.254 mm (1/1
00 inches) or greater, preferably about 0.794 mm (1/32 inch) or greater, and most preferably about 1.588 mm (1/16 inch) or greater. In a preferred embodiment, the deodorizing contact agent is about
Having an effective surface area of 1500 m ² /g or less, most preferably the deodorizing contact agent consists of one or more of the above metals or metal oxides incorporated into a porous carrier. The carrier used is preferably about 1 to 1000 m ² /g.
has a surface area of The deodorizing contact agent is a metal selected from the group consisting of nickel, cobalt, iron, palladium, rhodium, ruthenium, platinum, tungsten and copper (excluding Raney metal types of these metals) and at least partially reduced It can be made of any metal oxide selected from the group consisting of oxides of these metals. By contacting a crude isopropyl alcohol stream with such a deodorizing contact agent, a highly deodorized, commercially acceptable isopropyl alcohol stream can be produced. Preferably, about
An initial stream of isopropyl alcohol containing 0.0005 to 90% water is contacted with a deodorizing contact agent in a finishing operation to produce a final deodorized isopropyl alcohol stream preferably containing no more than about 0.01% water. In one preferred embodiment of this aspect of the invention, the isopropyl alcohol production finishing operation removes undesirable impurities from the overhead and
It consists of various distillation steps including a first distillation step in a column maintained at a temperature to produce a bottoms stream of isopropyl alcohol containing 60-90% water. Additionally, the preferred isopropyl alcohol finishing operation also includes a second distillation step at a temperature of about 75-150°C;
In this step, a modified isopropyl alcohol stream containing 9-15% water is removed overhead. In addition, this finishing operation removes the final isopropyl alcohol stream containing 9-15% water from the bottom of the column and removes various undesirable low-boiling components from the top of the column, about 75% water.
It is most highly preferred to include a third distillation step carried out at a temperature of -150<0>C. In these preferred finishing operations for the production of isopropyl alcohol, the contacting step with the deodorizing contact agent of the invention can be carried out at any stage, but it is preferably carried out before or after the third distillation step. The detailed description of the invention set forth below will be more easily understood by reference to the accompanying drawings. One important aspect of the present invention is that it can be incorporated into conventional processing methods for the production of various oxygenated compounds.
Simple, economically desirable because it does not interfere with the commercial production of these compounds and is useful for adapting to conventional methods so that final products with excellent odor properties can be produced. , to provide an effective method. Further, the deodorizing contact agent used in the present invention can be used in various states and can be brought into continuous contact with the stream to be deodorized without requiring regeneration for an extremely long time. The contacting method used in the present invention is relatively simple and primarily results in only deodorization of the deodorized stream without significant side effects and/or changes in the deodorized stream. In particular, the present invention has a number of advantages over prior art methods, such as those described in Japanese Patent Publication No. 1684/1984, which utilize Raney metals to improve the odor of isopropyl alcohol. Firstly, significantly lower yield losses can be realized during product purification because the selectivity to undesired by-products is much lower. Also, higher metal processing capacity, costly filtration and/or
Removal of metal contaminants in the product without the need for distillation techniques, significantly lower residence times, no undesirable waste streams and therefore clean ecological benefits, no need to add hydrogen during processing Also associated with the present invention is low overall cost. The isopropyl alcohol to be treated contains relatively small amounts of sulfur-containing impurities, typically less than about 100 ppb. The deodorizing contact agent must be suitable for use in fixed bed or fluid bed contact methods. especially,
The deodorizing contact agent must have the above minimum particle size and further have an effective surface area of about 1500
m ² /g, preferably about 1000 m ² /g or less, most preferably about 1 to 500 ^{m 2} /g. One way to obtain such deodorizing contact agents with such surface area is to incorporate the metal or at least partially reduced metal oxide into an effective porous carrier material. Such incorporation may be accomplished by various methods known in the art such as impregnation, ion exchange, co-precipitation and/or co-precipitation, or by incorporation of suitable surface stabilizing elements into the larger metal/metal oxide structure. or by other methods that produce highly dispersed metal/metal oxide surfaces. These carrier materials themselves may be of various types, including silica, alumina, silica/alumina, zeolites, diatomaceous earth, carbon, various clays, refractory oxides, and the like. A number of such special carrier materials and their surface area and pore volume properties are shown in Table 1.

[Table] Nickel, cobalt,
and preferably from the group consisting of iron, palladium, rhodium, platinum, tungsten and copper (excluding Raney metal types of these metals) and at least partially reduced oxides of these metals. are copper, tungsten, ruthenium, rhodium, nickel, platinum, cobalt, iron,
Palladium and combinations thereof, e.g.
Rh/Ni is used. However, some of the most preferred deodorizing contact agents include
There are several commercially available hydrogenation catalysts that can be used under the conditions of the present invention and do not act as conventional catalysts.
These include Girdler, WR Grace, Karsikat & Engelhard (Girdler,
Commercial hydrofining, such as that available from WRGrace Calsicat and Engelhard,
Includes hydrogenation, dehydrogenation, oxidation, ammonia synthesis and dissociation, reforming, hydrotreating and gas purification catalysts (in reduced or active form). Preferably, the deodorizing contact agent is used in a fixed bed contact column. Thus, the deodorizing contact agent preferably contacts the feed stream to be deodorized in a downflow manner. Such contacting is carried out at a temperature of 50-300°C, preferably 60-150°C, most preferably 60-120°C and generally 0-28.12°C.
Kg/cm ² gauge pressure (0~400psig), preferably
0.03515~17.575Kg/cm ² gauge pressure (0.5~250psig),
Most preferably, a pressure of about ¹ to 150 psig is suitable.
However, as mentioned above, these conditions can be chosen to be the least severe possible and most compatible with the particular process design using the method of the present invention. Furthermore, the contact is approximately 0.2~
50V/hr/V, preferably about 0.5-35V/hr/V,
Most preferably, it can be carried out at a space velocity of 1 to 24 V/hr/V. The present invention can be more fully understood by referring to FIGS. These figures illustrate the method of the present invention incorporated into a conventional isopropyl alcohol finishing scheme and also illustrate the relationship between sulfur content and odor in isopropyl alcohol. The same numbers in FIGS. 1 and 2 refer to the same parts. FIG. 1 shows such an isopropyl alcohol treatment and deodorization scheme. Thus, referring to FIG. 1, a crude feed stream is fed into extractive distillation column 2 from line 4. This feed stream generally consists of isopropyl alcohol and about 35-55% by weight water and other impurities such as isopropyl ether. Water is supplied into the column 2 through line 6 and steam is supplied through line 8. Temperature about 50-150℃, preferably 80℃
Undesirable impurities are removed overhead in column ² maintained at ~130°C and ^a pressure of 0-20 psig, preferably 5-15 psig. through line 10. These impurities include various ethers as well as other such undesirable components. The thus purified isopropyl alcohol stream, which also contains about 40-90% water, preferably about 60-90% water, is removed as a bottoms stream from line 12 and sent to column 14 for further distillation. In column 14, commonly referred to as the alcohol column, the isopropyl alcohol stream is further concentrated by removing water as a bottoms stream through line 16. This means that
The column 14 is heated to a temperature of about 75-150°C, preferably about 80-120°C.
°C, and pressure approximately 0 to 1.406Kg/cm ² gauge pressure (0
20 psig), preferably about 0.3515 to 1.0545 Kg/cm ² gauge pressure (5 to 15 psig). An isopropyl alcohol/water mixture containing approximately 9-15% by weight water is then removed from the top of the column through line 18 and heavy impurities are purged through line 45. Thus, the isopropyl alcohol/water mixture may be sent in the conventional manner through lines 20, 22 to another distillation column 24, or as shown in FIG.
8 and directly to such a distillation column 24, commonly referred to as an acetone column, to remove ketones such as acetone as a light fraction. According to the present invention, line 20 is optionally partially or completely closed off by means of a valve, and at least a portion of the isopropyl alcohol solution discharged from column 14 is routed through line 26 to the main cell in which the above-described fixed bed catalyst is held. The isopropyl alcohol/water mixture can be sent to the deodorizing tower 28 of the invention and passed over a fixed bed catalyst under the conditions described above. The resulting deodorized, substantially improved isopropyl alcohol/water stream can be sent from column 28 through line 30 and then into acetone column 24 through line 22. The temperature of the acetone column 24 is approximately 70 to 120°C, preferably 75 to 110°C.
℃ temperature and about 0~1.406Kg/ ^cm2 gauge pressure (0
~20 psig), preferably 0.3515 to 1.0545 Kg/ ^cm2 gauge pressure (5 to 15 psig). In this way, acetone and/or other ketones and light impurities contained in the isopropyl alcohol mixture are removed from the top of the column through line 32, while prime grade is removed from the bottom of column 24 through line 34. An isopropyl alcohol stream can be removed. This isopropyl alcohol stream generally consists of an azeotrope, containing about 91% isopropyl alcohol in water. The overhead distillate from line 32 containing acetone, a small amount of isopropyl alcohol, and a small amount of water is primarily a waste stream from acetone column 24. tower 24
The primary isopropyl alcohol taken out as a bottom product through line 34 can be further finished by dehydration treatment to produce isopropyl alcohol of 99% or more. Next, FIG. 2 will be specifically explained. As can be seen, the overhead stream distilling from column 14 through line 18, again consisting of isopropyl alcohol containing approximately 9-15% water, is sent directly to acetone column 24 for further distillation. be done. this tower 2
4 operates in the manner described for acetone column 24 in the scheme of FIG. However, in this case,
The deodorizing tower 28 of the present invention is placed downstream of the tower 24,
The primary isopropyl alcohol product removed from 4 through line 34 is not directly sent out of the system through line 36, but is sent through line 38 to column 28 for contact with the deodorizing contact agent of the present invention. can do. This deodorized isopropyl alcohol stream can then be removed through line 40 and line 36. Next, FIG. 3 will be explained. As can be seen, a lower amount of sulfur present in an isopropyl alcohol sample does not necessarily mean that the sample has a lower detected odor. This suggests that the odor-causing impurities present in lower alcohols may be other than simple sulfur compounds, and that the deodorizing metals or metal oxides used in the present invention are well known in the prior art. It also suggests that it may act through a mechanism different from that shown. Although the flow plans shown in Figures 1 and 2 are representative of some embodiments of the present invention, deodorization towers in particular are extremely sensitive to various conditions such as temperature, pressure, space velocity, and flow composition. It goes without saying that because of its flexibility, and because the deodorization tower can be used over long periods of time and does not cause splitting of the process stream, it can be placed in many different locations in an isopropyl alcohol finishing plant. The invention can be understood more fully by reading the examples given below. Example 1 300 ml of a 91% isopropyl alcohol product (not for sale, off-spec material) with a 12+RHB odor rating was added in a 500 ml flask to 30 g 3.175 mm (1/8 inch) tablets of active ENCAR hydrogenation catalyst having the following characteristics: It was also heat soaked. Type: Co-precipitated nickel-copper-silica-diatomaceous earth catalyst Ni content: 45% by weight Cu content: 4.5% by weight BET surface area: 250m ² /g Apparent bulk density: 0.848g/cm ³ (55lb/ft ³ ) Crushing strength :3.178Kg (7lb) [3.175×3.175mm (1/
(8 x 1/8 inch) tablets] Cumulative pore volume: ~0.35 cc/g Contacting was carried out at normal pressure and a temperature of about 78°C for about 2 hours. The obtained isopropyl alcohol was evaluated by an order panel (Odor Panel). The product was determined to be comparable to cosmetic quality alcohol and free of recycle odor. The results are shown in Table 2. Example 2 The following properties: Type: Ni on diatomaceous earth Ni content: 58% by weight BET surface area: 160m ² /g Apparent bulk density: 1.44g/cm ³ (90lb/ft ³ ) Crushing strength: 4.086Kg (9lb) [3.175×3.175mm
(1/8 x 1/8 inch) tablet] Harshaw Ni−0104T− with cumulative pore volume: ~0.20cc/g
72 g of a commercially available hydrogenation catalyst, available from Harshaw as 1/8 Hydrogenation Catalyst, was contacted with 300 ml of a 91% isopropyl alcohol product having an Odor Class of 12+RHB in a 500 ml flask. The temperature of this system was maintained at about 80° C. for 3 hours at normal pressure. The obtained isopropyl alcohol was graded on an order panel.
The results are shown in Table 2. The product was determined to be cosmetic quality and free of recycled odor. Example 3 The following properties: Type; Ni supported on support Ni content: 52% by weight BET surface area: 145 m ² /g Apparent bulk density: 1.088-1.104 g/cm ³ (68-
69lb/ ^ft3 ) Crushing strength: ~8.172Kg (18lbs) [3.175×3.175
mm (1/8 x 1/8 inch) tablets] 56 g of a commercially available hydrogenation catalyst sold as Hirschau Ni-3250T-1/8 hydrogenation catalyst having a cumulative pore volume of ~0.32 cc/g.
Approximately
Heat immersion was performed at a temperature of 80°C for 3 hours. The obtained isopropyl alcohol was graded by an order panel, and the results are shown in Table 2. The product was determined to be cosmetic quality and free of recycled odor. Examples 4-7 The procedure of Example 3 was repeated in these four examples. However, in each example, the same Hirschau Ni−
3250T-1/8 hydrogenation catalyst was reused. In each case the isopropyl alcohol obtained was graded by an order panel. The results are shown in Table 2. These products were also determined to be of cosmetic quality and free of circulating odors. Thus, it was shown that the effectiveness of this deodorizing contact agent did not decrease during continued product processing.

[Table] Example 8 In order to compare the method of the present invention with the method of Japanese Patent Publication No. 51-1684, a supported nickel contact agent according to the present invention (commercially available Hirschau Ni-3250T supported nickel hydrogenation catalyst) and Raney nickel were used to compare the method. The odor of isopropyl alcohol was improved by post-treatment deodorization under these conditions. The results obtained are the third
Shown in the table. In addition to the results shown in the table, the method of the present invention, compared to the method of the Japanese patent mentioned above, does not require filtration or distillation of the product after treatment, has no problems of catalyst separation or waste stream dumping, and has no problem with the system. It was also recognized that there was no need to use hydrogen in

EXAMPLE 9 A stream of 91% isopropyl alcohol with a 12+RHB odor rating is continuously pumped through a 2 inch diameter pipe filled with commercially available Hirschau Ni-3250T hydrogenation catalyst. Flow rate of about 1 to 24 volumes of isopropyl alcohol per hour per volume of nickel contact agent and a temperature of 55 to 85°C and normal pressure to 17.575 Kg/cm ² gauge pressure (250 psig)
pressure was used. The treated isopropyl alcohol product has a significantly improved odor rating from a malodorous feedstock to a product similar to cosmetic grade.
Moreover, the resulting product does not contain detectable amounts of residual metals and contains 10,000
The bed remained effective even after processing more than 1 volume of isopropyl alcohol. Examples 10-16 Approximately 300 ml of 91% isopropyl alcohol of 12+RHB odor rating is treated in a 500 ml flask at a temperature of approximately 80° C. for approximately 3 hours with approximately 15 g of a series of various deodorizing metals listed in Table 4. did. The resulting isopropyl alcohol stream was graded by an order panel and determined to be recirculated odorless and suitable for odor sensitive end uses.

[Table] Example 17A 12+RHB odor grade 91% isopropyl alcohol packed with Ni-3250T-1/8 catalyst 25 c.c.
Inside the 12.7 mm (1/2 inch) pipe, at normal pressure and temperature of approximately 80°C.
It was pumped at a space velocity of 4.0V/hr/V. The treated isopropyl alcohol was determined by an order panel to have significantly improved odor ratings, completely eliminate unpleasant odors, and to be suitable for low odor alcohol end use. Example 17B The same 91% isopropyl alcohol with 12+RHB odor grade was mixed with equal volume of Ni-3250T-1/8 catalyst and 0.5
%Rh/ _Al2O3T -1/8 catalyst was pumped through a 12.7 mm (1/2 inch) reaction tube packed in _the tube such that the nickel catalyst contacted the alcohol before the rhodium catalyst. . The odor treatment conditions used were the same as those described in Example 17A. The product alcohol was judged by the order panel to have a superior odor rating to the refined alcohol produced in Example 17A. Example 18 A series of untreated isopropyl alcohol samples were first collected from Houston Atlas, Inc.
Houston Atlas Sulfer Analyzer (Houston Atlas Sulfer Analyzer) from Houston Inc.
Analyzer) to measure the sulfur content,
Next, an order panel odor evaluation was performed to determine whether a fundamental relationship existed between the sulfur content in the isopropyl alcohol sample and the level of unpleasant odor detected. The results are as plotted in Figure 3, and it was concluded that there is no direct relationship between the two. The above description of the invention and its particular embodiments is intended to be illustrative only and not limiting. It is intended that the invention be limited not by the theory and description presented, but only by the scope of the claims.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a process plan for producing isopropyl alcohol incorporating the present invention, FIG. 2 is a schematic diagram of another process plan for producing such isopropyl alcohol, and FIG. 3 is a schematic diagram of an isopropyl alcohol sample. FIG. 3 is a diagram showing the relationship between the sulfur content of and the intensity of the detected unpleasant odor. Brief explanation of drawing numbers, 2: Extractive distillation column, 4:
Feedstock supply line, 6: Water supply line, 8: Steam supply line, 10: Impurity removal line, 1
2: Bottom product removal line, 14: Alcohol column, 16: Water removal line, 18: Isopropyl alcohol/water mixture removal line, 45: Heavy impurity purge line, 24: Acetone column, 28:
Deodorizing tower.

Claims (1)

[Scope of Claims] 1. Metals selected from the group consisting of nickel, cobalt, iron, palladium, rhodium, ruthenium, platinum, tungsten and copper, and not containing the Raney metal type, and at least partially reduced metals thereof. A method for deodorizing crude isopropyl alcohol, which comprises bringing a deodorizing contact agent selected from the group consisting of metal oxides into contact with crude isoropyl alcohol by a fixed bed contact method. 2 The above deodorizing contact agent is 0.254 mm (0.01 inch)
A method according to claim 1, having a larger particle size. 3. A method according to claim 1 or 2, wherein the deodorizing contact agent has an effective surface area of less than 1500 m ² /g. 4 Claims 1 to 3, wherein the deodorizing contact agent comprises the metal incorporated into a porous carrier.
The method described in any of the paragraphs. 5. The method of claim 4, wherein the porous support is selected from the group consisting of silica, alumina, silica/alumina, carbon, clay, zeolates, refractory oxides, and mixtures thereof. 6. The method according to claim 4 or 5, wherein the porous carrier has an effective surface area of 1/1000 m ² /g. 7 The above crude isopropyl alcohol is 0.0005-90
2. A method according to claim 1, containing % water by weight. 8. The method of claim 7, wherein the crude isopropyl alcohol is a product stream from an alcohol dehydration process. 9 In the first column, temperature 80-130℃, pressure
Distilling the isopropyl alcohol stream at 0.3515 to 1.0545 Kg/cm ² gauge pressure (5 to 15 psig) to produce an isopropyl alcohol liquid stream containing 40 to 90% by weight water and undesirable impurities from the bottom of the first column. 8. The method of claim 7, comprising producing an overhead vapor stream from said first column comprising: 10 A vaporized isopropyl alcohol liquid stream containing 40 to 90% water by weight is fed into a second column at a temperature of 80 to
120℃, pressure 0.3515-1.0545Kg/cm ² gauge pressure (5
~15 psig) and 9-15% from the top of the second column.
A highly concentrated isopropyl alcohol liquid stream containing water, a bottoms stream consisting of water from the column bottom, and a side stream consisting of heavy impurities from the side of the column. The method described in Section 9. 11. Condensing an overhead vapor stream consisting of isopropyl alcohol and adding said isopropyl alcohol stream containing 9 to 15% water at a temperature of 75 to 110°C and a pressure of
Distilled in a third column maintained at 0.3515-1.0545 Kg/cm ² gauge pressure (5-15 psig) to produce a highly pure isopropyl alcohol stream containing 9-15% water from the bottom of the third column as a liquid. 11. A process as claimed in claim 10, including removing the column in the same state and removing from the top of the column an overhead stream comprising light impurities. 12. The method of claim 11, wherein the isopropyl alcohol overhead stream from the top of the second column is contacted with the deodorizing contact agent.