JPS607937A - Preparation of adsorbent for heavy metal - Google Patents

Abstract

PURPOSE:To prepare adsorbent for heavy metal of high performance inexpensively by crushing coal waste having a specified amt. of ash and carbonizing the coal waste after molding it. CONSTITUTION:Coal waste having 40-80wt% ash content is crushed, if necessary after drying, to <=100 mesh grain size. The crushed product is then mixed with an appropriate amt. of water and molded to desired shape and size. Tablets of 3-5mm. phi and 4-10mm. thickness are usually preferred usually because of its better water permeability and convenience in use when it is packed in a packed layer. The molded product is dried and charged to a carbonizing oven and is heated slowly to 700-1,000 deg.C in neutral or reducing atmosphere, maintained at the temp. for 5min-1hr to complete carbonization. The temp. elevating rate depends upon the size and shape of the molded product, but 3-20 deg.C/min is usually adequate. Obtd. adsorbent for heavy metals has extremely high adsorptivity for heavy metals such as Cd, Cu, Pb, ett.; the pressure drop in the stage of loading water is small, the material has high strength and high water resistance, and is durable for long term use and recurrent use after regeneration and inexpensive.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a chemical agent useful for treating industrial wastewater, etc., which contains a heavy metal chloride.

Many of the wastewater from the chemical industry or mining industry in Tanishin contains the divine Shigekin Suchi, and strict discharge regulations are in place to prevent environmental pollution. Various treatment methods have been used for wastewater containing these metals, including the hydroxide precipitation method and the sulfide precipitation method.

Reduction method, flotation method, ferrite method, ion exchange method.

1! The waste sludge is treated using the most suitable treatment method for each type of sludge, such as the 7i method. and environmental group 3
In cases where the 17% value is severe and extremely sophisticated treatment is required, it is said that the best method for treating wastewater is the absorption method using activated carbon, ion exchange resin, etc. However, although this endothermic method is particularly effective in removing pollutants, it requires a relatively expensive adsorbent, which limits its practical application from an economic standpoint. The development of a new adsorbent is desired.

Traditionally, it has been used to treat wastewater containing this type of heavy metal IA,
In addition, adsorbents that have died due to disease include ionic father exchange resins, activated carbon, and silicates, but they are all relatively expensive, and most are in powder form and difficult to handle, making them unsuitable for treating large amounts of wastewater. It was appropriate.

In order to treat wastewater in a packed bed format suitable for treating large amounts of wastewater, it is convenient to use these adsorbents in a molded form, but in that case, the shape of the molded material is too small! There were problems such as the Ii strength was weak and could not withstand long-term or repeated use, the specific surface area decreased due to molding and the pressure loss increased, and the adsorption capacity decreased. It also molds coal,
Molded activated coke obtained by carbonization activation is also used as an adsorbent, but it has poor adsorption capacity for heavy metals.

Akira Motomoto et al.
! As a result of various studies, -iA contains ash at a reasonable ratio of 41'
Conventional σ)
This high-performance gunkin sorbent is available at a low price with its shortcomings improved.
The present invention has found that it is possible to produce a coal with an ash content of 40 to 80% by weight.
This is a method for producing 31i gold 1.hesi(')ki 11 by carbonizing ~1000'ct.

The heavy metal adsorbent of the present invention is manufactured as follows. Coal shavings with an ash content of 40 to 80% are dried as necessary, and then 100 ml of coal is poured into the lower particle size.
crush. Next, add an appropriate amount σ) of water and mix thoroughly.
Mold into desired shape and size - usually 3 to 5
When a tablet type of n+mφ×4 to 1offlIl+ is filled in a packed bed, water permeability is good and easy to use. σ)15
Put the 5E type r snout into a drying Q) A-temperature drying furnace and gradually raise the temperature to 700 to 1000°C in a neutral or reducing atmosphere.
Hold for 5 minutes to 1 hour to complete carbonization. The heating speed depends on the size of the molded product.

Although it depends on the shape, a temperature of approximately 3 to 20°C per minute is appropriate.

If the heating rate is too low, it may cause partial expansion or cracking of the molded product, making it impossible to produce a homogeneous and strong madder product.Also, if the carbonization temperature is too low, the specific surface area will be small and the strength of the product will be reduced. It is not strong, and the components in the ash do not react properly.
As a result, it does not show strong sucking power. Maximum carbonization temperature is 100
A temperature of about 0°C is sufficient; increasing the temperature any further will waste energy (σ) and reduce the performance of the swamp absorbent.

There is little ash content in the coal pile.
The suction ability of the particles is reduced, and the viscous force of the particles is reduced, making it difficult to mold. Furthermore, if the ash content is too high, the properties such as the pore structure 1 strength of the product will deteriorate.

The raw material, coal shavings, is a secondary product made from coal-containing clay minerals produced from coal mining, coal preparation, and culm, and can usually be used without adjusting the ingredients. The components of botata differ depending on the coal production area and coal preparation processing method, so if a specific component is lacking, replenish the necessary components 1-
In particular, it is good to adjust the λ component before use. Among these, coal slime containing finely divided coal as a main component is particularly suitable for use as a raw material in the present invention. Furthermore, if a pot with a high calcium content (for example, Miike charcoal pot) is used, it will have a high ability to trap heavy metals, and the pH of the treatment solution is generally not suitable for heavy metal excitation treatment. Since it is on the alkaline side, it is a good value of 4115.

In this manufacturing method, how does the v+11'' contained in the raw materials react in the dry box?
I wonder if it exists in the form of J or not, but it is probably because the silicon and calcium components are combined with other components contained in the bottle in a complicated form, increasing the absorption performance. The carbonic acid content fulfills its role as a binder, creates a reducing atmosphere in the furnace, and creates a product with a large specific surface area and low pressure loss.
) is considered to be helpful in the formation of 1 dahara A゛1
Contains coal components and clay components in appropriate proportions.
There is an option that requires a special molding binder and can be molded using only water.

Akira Honji Q) According to the method, high performance polymerization number 1. The heavy metal adsorbent produced by the method of the present invention has the following characteristics, and one heavy metal contains no stone. Treatment of wastewater, especially 6-fill Jti7
Suitable for formal processing.

l) Extremely high ability to absorb and disintegrate heavy metals.

2) It has a large specific surface area, has 11 pores with a suitable size of 4'44, and each grain is evenly spaced, so uniform charging is possible with a charging density of 0.8" or more. Yes 1 water + 1! ]
3) The product σ) has high strength and is water-resistant, so it can withstand long-term use and repeated TLR growth.

4) It is inexpensive because the raw materials are easily available and the preparation is simple and easy to manufacture.

Look, bottom'X b1Q+? 't, ratio i1*Efl
m Reference Example K Yo') Book A Akira &) The 7j method will be explained in detail.

Examples and Comparative Examples Coal shavings having the composition shown in Table 1 were dried and ground to a particle size of 200 mesh or less. Then add a little water.

The well-mixed mixture was molded into tablets of 11φ x 5 bars in 3 plates using a beretter. After drying this molded product, it was charged into a small rotor IJ-kiln adjusted to 300-350°C and gradually raised to 171' AL under the conditions shown in Table 2, followed by carbonization and cooling to obtain a product. Table 2 shows the manufacturing conditions and I-nasality values of each product.

In addition, the strong people in 3y = 2 were sidekicked in the following manner.

Using the equipment on the side of the Roca test method described in J I 8-J+-s 801, first charge 35 f of 1 or more h·(35 f) into the rotating drum. 100
After 0 revolutions (50 rpm), sift the contents through a No. 11 sieve. Displayed in the following format: The strength after being immersed in water for 1 hour was determined by immersing the sample in water for 48 hours and then drying it.

411] added by the above method Reference A 511 A Tanidoku heavy metals σ) thermoabsorption test was conducted using the heavy metal swamp absorbents and other swamp absorbers produced according to the Examples and Comparative Examples.

(Test method l) 101) Prepare standard solutions in which various metal ions are dissolved so that I) m O) concentration r [100M of each standard solution.
After taking e and adjusting p)] to 5 levels of 2.4, 6, 8.10, the heavy metal absorbent and other absorbent of central h'D example and comparative example were crushed and θ) respectively. 0.45'7 was added and after shaking for 2 hours, the solution was separated and the metal ions remaining in the P solution were removed. fi at optimum pH value
Table 3 shows the results of 11 pairs of heavy gold 11 mouth suction AI of the example.
It can be seen that the use of the drug effectively removes vomiting.

The sample of Comparative Example-1, which has a low carbonization temperature, has a low glare 7a ability, and the sample of Comparative Example-2, which has a low ash content in the be. Furthermore, in Comparative Example-3 with high ash content and L℃, the product strength was +
Ks- decreased significantly.

(Trial 1, Method 2) Heavenly Example 10 Heavy metal machine absorbent 7 o m, e 141no+
Fill a φ glass tube to a height of -150m+n with heavy metal 15
4) Pass the bath solution at a rate of 700 m4/h + θ) and sample the filtrate every 2 hours to determine the remaining #
Measure the current L 7;:. The results are shown in Figure 1, and it can be seen that the particles were efficiently removed over a long period of time.

Table 1 4, (Simple publication on page 1) Figure 1 shows a patent for an absorbent Q that is similar to real Ir10111) Mitsui Mining Co., Ltd.

Claims (1)

[Claims] 1. Crush coal shavings with an ash content of 40 to 80% by weight,
After molding the pulverized material, the maximum temperature is 700-1000℃.
A method for producing a heavy metal tIi absorption agent, which comprises carbonizing the heavy metal tIi absorbent.