JPS6229368B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to spherical activated carbon, which is made of spherical activated carbon in which at least 85% of the activated carbon is true spheres, and is suitable for removing and detoxifying poisons or harmful substances from the digestive system, and a method for producing the same. More specifically, the present invention shows that when activated charcoal is taken to detoxify harmful substances that exist or are produced within the digestive system such as the stomach and intestines, the constipation side effect that has been a problem in the past has been demonstrated. The present invention relates to a spherical activated carbon suitable for an antidote, in which at least 85% of the activated carbon is true spheres, and a method for producing the same. Activated charcoal has long been known to be effective in treating intestinal diseases and the like when ingested, and is used to treat many diseases. By taking activated charcoal, it has a particularly excellent therapeutic effect on dysentery, cholera, typhoid fever, bacterial infections such as food poisoning, indigestion, intestinal tension, chronic gastritis, epilepsy, dizziness, yellowing disease, anthrax, etc. It has been reported that it shows. In addition, detoxifying effects have been obtained by taking activated charcoal as an emergency when ingesting drugs or poisonous substances. Furthermore,
Taking activated charcoal is also effective in removing harmful substances in the digestive system that are produced due to metabolic abnormalities associated with various other diseases. These effects are thought to be due to the fact that toxins, abnormal metabolites, or substances that produce toxins or cause metabolic abnormalities in the digestive system are adsorbed by activated carbon, which is completely non-toxic to living organisms, and are excreted from the body along with the activated carbon. It is being Conventionally, powdered activated carbon has been used for the purpose of detoxification, and this powdered activated carbon has been taken with water or in the form of a suitable tablet. Even when taken as a tablet, it is unlocked within the body and turns into a powder, which exhibits the same adsorption capacity as when taken with water. However, the use of powdered activated carbon caused constipation as a side effect, which was a major drawback. In particular, since activated charcoal is usually taken to treat various diseases, patients' physical strength is often exhausted, and the constipation that occurs as a side effect is not only extremely painful for the patient, but also Conventional activated carbon has the disadvantage that if it does not have sufficient excretion power, it may be life-threatening unless it is removed mechanically. In view of this situation, in order to solve the above-mentioned drawbacks, the inventor of the present invention has conducted extensive research and found that a specific spherical activated carbon in which at least 85%, preferably 90% of the activated carbon is true spheres has an excellent detoxifying effect. The present invention was achieved based on the discovery that the present invention has the following properties and does not exhibit constipation side effects. The antidote according to the invention is prepared from a high molecular weight hydrocarbon, such as pitch, by the following described process consisting of two steps. In the first step, pitch is made into small spherical particles in a molten state, cooled, oxidized to make it infusible, then carbonized at a temperature of 800 to 1000°C in an inert atmosphere, and then carbonized at a temperature of 900 to 1000°C in a steam atmosphere. Activated with 0.05~2mm diameter, surface area 500~ ^2000m2 /g, pore radius
Pore volume 0.05-1.0ml/ in the range 100-75000Å
g, to produce microspherical activated carbon with pH=8-10. In the second step, these spherical activated carbons are heated with 1 NH ₃
~1000ppm, preferably by contact treatment with a dilute ammonia aqueous solution containing 5 to 100ppm and drying, to have the same diameter, surface area and pore volume as the spherical activated carbon before the ammonia treatment, compared to the spherical activated carbon before the ammonia treatment. Microspherical activated carbon with a pH of 6 to 8 is produced. The product consists of microspherical activated carbon in which at least 85% of the activated carbon is true spheres, the activated carbon has a smooth convex surface with no noticeable edges, and the ratio of maximum diameter to minimum diameter is 1.0―
It is 1.3. If the particle size (diameter) of spherical activated carbon is 0.05 mm or less, it will not be sufficiently effective in eliminating constipation side effects, even if it has a detoxifying effect. Furthermore, if the particle size of the spherical activated carbon exceeds 2 mm, it will not only be difficult to take, but also the desired detoxifying effect will not be achieved quickly. The shape of the activated carbon is one important factor in obtaining the satisfactory pharmaceutical effects of the present invention, and it is necessary that it be substantially spherical. More specifically, at least 85% of the activated carbon needs to be true spheres. Similar to the shape, the surface area and pore volume of activated carbon are also important factors in achieving sufficient detoxification and eliminating constipation side effects at the same time.
In other words, if the surface area and pore volume of activated carbon are too small, the adsorption power will be weak and a practically sufficient detoxification effect will not be obtained, and if the surface area and pore volume are too large, even if the activated carbon has a detoxifying effect, it may also cause constipation. That's what happens. Furthermore, when the surface area and pore volume of activated carbon are larger than the range of the present invention, the strength decreases, the shape collapses during or after ingestion, and powdering occurs, which is also considered to be a cause of constipation side effects. The surface area of the microspherical activated carbon of the present invention is 500 to 2000 m ² /
g, preferably 700 to 1500 m ² /g. The pore volume is 0.05 in the pore radius region of 100 to 75000 Å when measured with a commercially available mercury intrusion borosimeter.
-1.0ml/g, preferably 0.1-0.8ml/g. Raw materials used to produce activated carbon with such characteristics include sawdust, coal, coconut shells, pithus,
Any known raw materials such as organic synthetic polymers may be used,
Spherical activated carbon can be produced from these materials. For example, to produce the desired spherical activated carbon, powder raw materials are granulated into small spherical shapes using a binder such as pitch, and then 800 g
There is a method of carbonizing by heating to ~1000°C and activating at 900~1000°C in a steam atmosphere. On the other hand, for example, according to the method disclosed in Japanese Patent Publication No. 50-18879, pitches are made into small spherical shapes in a molten state, and then made infusible by oxidation, and then carbonized by heating at 800 to 1000°C in an inert atmosphere. Spherical activated carbon can be produced by a method of activation at 900 to 1000°C in a steam atmosphere. In particular, the latter method is suitable as the method for producing activated carbon of the present invention, since smooth spherical activated carbon with a high sphericity and high strength surface can be obtained. The second step of the method for producing activated carbon microspheres of the present invention is a particularly important process. PH of spherical activated carbon
is usually PH=8~10, but this is PH=6~8
Change to By performing this second step, the spherical activated carbon has excellent properties. The conditions for treatment with aqueous ammonia solution vary depending on the state of the spherical activated carbon that has been treated with steam, but
Usually, the concentration of NH ₃ in ammonia aqueous solution is 1 to
1000ppm, preferably 5-100ppm, the volume ratio of ammonia aqueous solution and spherical activated carbon is 1-50, preferably 2-10, the treatment temperature is 10-50℃, and the treatment time is
It is 0.5 to 5 hours. _NH3 in aqueous ammonia solution
When the concentration of is higher than the range mentioned above, the product
PH also increases and becomes alkaline, and NH ₃
When the concentration of is low, the PH of the product remains in the alkaline region. It is not clear why spherical activated carbon, which exhibits alkalinity, changes to acidic-neutral spherical activated carbon when it comes into contact with an alkaline reagent, that is, an aqueous ammonia solution, and furthermore, such a change in PH is completely unexpected. It was hot. Next, the spherical activated carbon thus treated with the aqueous ammonia solution is dried at a temperature of usually 100 to 150°C and sieved into sizes suitable for administration. Adjusting the product to a uniform size, ie sieving to a range of sizes, is preferred for dosing. Sieving is carried out before the ammonia aqueous solution treatment in order to obtain spherical activated carbon with a diameter ratio of the largest particles to the smallest particles of 1 to 1.3. In any case, since the spherical activated carbon is to be taken, it must of course be of sufficient purity for safety. The purity test must be passed. The method for taking the spherical activated carbon according to the present invention may be the same known method as for ordinary activated carbon. Although it is easiest to take the microspherical activated carbon according to the present invention by suspending it in drinking water, it is also possible to take the spherical activated carbon in the form of an appropriately shaped tablet according to a conventional method. However, in this case, of course, it is necessary to unlock the original spherical activated carbon particles within the body so that the spherical activated carbon of the present invention can exhibit its effects. It may also be taken in a conventional cylindrical capsule according to a conventional method. The dose of spherical activated charcoal varies depending on the severity of the disease, the need for emergency detoxification, etc., but it is usually 0.5 to 10 g per dose.
g, about 3 times a day. Also, it is preferable to take the drug between meals, but of course this does not apply if there is an emergency. It was completely unexpected that the spherical activated carbon of the present invention would maintain the detoxification effect and show a remarkable effect on eliminating constipation side effects, and although the cause is still unclear, the spherical activated carbon of the present invention does not require ammonia treatment. Because of its special surface condition, it has the ability to adsorb exogenous and endogenous harmful substances. That is, the spherical activated carbon of the present invention can be used for ingested food,
Even in the presence of digested food and its digested products,
It has superior adsorption ability compared to conventional powdered activated carbon or activated carbon made from powdered activated carbon into spheres or agglomerates. Conventional powdered charcoal or spheroidized or agglomerated powdered charcoal also adsorbs substances that stimulate intestinal motility, weakening intestinal motility, and at the same time mix well with stool, increasing the cohesive force of stool and causing constipation. On the other hand,
Since the spherical activated carbon of the present invention is a smooth sphere with different surface properties, it does not have the effect of increasing the cohesive force of stool, and at the same time adsorbs few substances that stimulate intestinal motility, and the spherical activated carbon provides moderate stimulation to the intestines. It is also presumed that constipation will not occur due to the combined effect of feeding. EXAMPLES Hereinafter, the effects of the present invention will be explained with reference to Examples, but the scope of the present invention is not limited in any way. Example 1 (Production of spherical activated carbon) Pitch obtained by high-temperature decomposition of crude oil (softening point
175℃, nitrobenzene insoluble content 25%, H/C element ratio
0.63) 750 parts of naphthalene and 250 parts of naphthalene were placed in a stainless steel autoclave equipped with a stirrer, mixed and dissolved at 170°C, and added with 3000 g of a 0.5% aqueous solution of "GOHSENOL GH-17" (polyvinyl alcohol suspension agent made by Nippon Gohsei). After stirring vigorously at 130° C. for 60 minutes, the mixture was cooled to room temperature while stirring to obtain true spherical particles. After separating most of the water, 5 of the particle weight
After being immersed in twice the amount of methanol and shaking to extract and remove naphthalene, it was dried with ventilation, and then 25°C/Hr while blowing air in a small rotary kiln.
The temperature was raised to 300°C to obtain inaccessible spherical particles.
Next, the air supply is stopped, and steam is supplied instead to raise the temperature to 900℃, thereby carbonizing.
Furthermore, activation is promoted by keeping it at this temperature,
Highly spherical activated carbon with a particle size of 0.1 to 1.5 mm was obtained. Two types of spherical activated carbon with different degrees of activation were produced by changing the activation time. Comparative sample No. 1 has a low degree of activation, and comparative sample No. 2 has a high degree of activation, and both have spherical sizes adjusted by sieving. Next, a portion of each of the spherical activated carbons of Comparative Sample No. 1 and Comparative Sample No. 2 was added to an ammonia aqueous solution with an NH ₃ concentration of 10 ppm at a volume/weight ratio of the ammonia aqueous solution and the spherical activated carbon of 10 ml/1 g. , at room temperature 3
Soaked for an hour. Subsequently, the spherical activated carbon was taken out from the solution and dried at a temperature of 110° C. for 16 hours to produce spherical activated carbon. Sample product from activated carbon with low degree of activation
Sample No. 1 and the product from activated carbon with a high degree of activation are Sample No. 2. Table 1 shows the properties of these four activated carbons. The adsorption capacity was determined by an in vitro test to measure the adsorption capacity for creatinine and uric acid. The two substances mentioned above are well known as harmful substances that are produced in the body due to metabolic abnormalities such as renal disease.

【table】

[Acute toxicity test]

An acute toxicity test using mice was conducted on the samples shown in Table 1. The results are shown below, and it was confirmed that the spherical activated carbon of the present invention is extremely safe even when administered in large amounts. Commercially available ICR-JCL female mice (body weight 22±1 g) were used as experimental animals, and the four samples shown in Table 1 were orally administered by force using a gastric tube. After one week, the Litchfield-Wilcoxon method was used to determine whether the animal was alive or dead.
Asked for _LD50 . The results are shown in Table 2. One week later, the animal was dissected, but no notable abnormal findings were found in the external appearance or internal organ observation, nor were any notable toxic symptoms observed.

[Table] Example 2 (Animal experiment) Using female Wistar rats weighing 130 to 140 g, bentobarbital-Na was administered at 20 mg/day.
It was orally administered as an aqueous solution to a body weight of Kg.
Immediately thereafter, the samples shown in Table 1 were orally administered as an aqueous suspension at a concentration of 200 mg/Kg body weight. At the same time, a comparative test was conducted in which activated charcoal was not administered. Ten specimens were used for each activated carbon sample administration group and non-administration group. Next, the average value of the maximum concentration of bentobarbital-Na in the blood was determined, and the ratio to the concentration in the comparative test group was calculated as the removal rate. The results are shown in Table 3. As is clear from Table 3, detoxification effects were observed in all groups administered with the spherical activated carbon samples. However, Samples No. 1 and No. 2 (those treated with ammonia) had particularly remarkable detoxifying effects compared to Comparative Samples No. 1 and No. 2 (those not treated with ammonia).

[Table] Next, 90 minutes after the administration of activated charcoal, these sample groups were killed by anesthesia, the gastrointestinal tract was removed, and the degree of intestinal transport of activated charcoal was compared. That is, the ratio of the transfer distance to the activated carbon reaching part to the total length from the cardia to the end of the rectum was determined as the transfer rate. As shown in Table 4, the results show that in the sample group using the activated carbon samples of the present invention shown in Table 1, the transport rate was high and the constipation effect was small.

[Table] Example 3 (Adsorption capacity) In order to examine the actual adsorption capacity of the spherical activated carbon of the present invention, the following experiment was conducted in the presence of sodium stearate, which prevents activated carbon from adsorbing harmful substances in the intestines. . Sodium stearate was dispersed in a phosphate buffer solution with a pH of 7.4 to a concentration of 2%, which is the approximate concentration of sodium stearate in the intestine, and creatinine was further added to the above solution at a concentration of 15 ml/dl. Dissolved. Each sample from Table 1 was then added to the above solution and shaken for 3 hours, after which time the mixture was divided into 5 ml portions. After adding 3 drops of a 10% aqueous solution of aluminum sulfate to the mixture to precipitate the stearic acid, the concentration of creatinine in the surface layer was determined by colorimetric method. All except the measurement process using colorimetric method are 37
The experiment was conducted at a temperature of ℃. The results of the measurements are shown in Table 5. As is clear from Table 5, the spherical activated carbon of the present invention is a comparative sample (not subjected to ammonia treatment).
It has superior adsorption ability compared to As a result, it is clear that the spherical activated carbon of the present invention has an excellent ability to absorb harmful substances such as creatinine even in the presence of substances such as sodium stearate that prevent activated carbon from adsorbing harmful substances in the intestine. It is.

[Table] Amount of tinine in mg

Claims (1)

[Claims] 1. By molding pitches in a molten state into small spherical shapes, cooling them, oxidizing them to make them infusible, heating them in an inert gas to carbonize them, and then heating them in steam to activate them. In a method for producing spherical activated carbon in which 85% of the total amount is true spheres,
The spherical activated carbon was treated with an ammonia aqueous solution containing 1 to 1000 ppm of NH ₃ at a volume ratio of 2 to 10 at a temperature of 10 to 50°C.
Treated for 0.5 to 5 hours, then dried at a temperature of 100 to 150°C, and sieved to obtain spherical activated carbon having a ratio of maximum diameter to minimum diameter between particles of 1 to 1.3. A method for producing an oral antidote.