JPS61436A - Fluidizing and stabilizing additive and manufacture thereof - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Related to manufacturing method.

In particular, the present invention relates to fluidizing and stabilizing additives for suspensions containing a solid phase in a liquid phase, and to methods for making the same.

More particularly, the present invention relates to fluidizing and stabilizing additives for liquid suspensions of coal and methods of making the same, and to stabilizing additives and methods of making the same.

In particular, the invention relates to fluidizing and stabilizing additives for aqueous suspensions of coal containing a high content of coal, for example above 60 parts by weight, in particular from 70 to 80 parts by weight or more;
and its manufacturing method.

In the following description, reference is made to coal/water suspensions, but the additives of the invention are useful in any field where there are problems with fluidization and stabilization due to the presence of suspended solids. It can be used.

Fluidizing and stabilizing additives for aqueous coal suspensions are known from compounds obtained by sulfonating and neutralizing tar. Such sulfonated compounds can be obtained by reacting tar with anhydrous concentrated sulfuric acid or fuming sulfuric acid. This conventional sulfonated additive has the disadvantage of containing large amounts of sulfonated alkali or sulfonated ammonium, which is produced when the sulfuric acid solution containing the sulfonated tar product is neutralized with alkali or ammonium hydroxide. Because an excess amount of sulfuric acid is used to sulfonate the sulfuric acid, if the water used to supply the neutralizing agent is removed, the sulfuric acid alkali will be present in the neutralized sulfonated tar. Or ammonium sulfate remains.

A second drawback of the known additives is that in order to have good viscosity properties they must be at least partially condensed with formaldehyde, which requires a very expensive process. There is a need.

The inventors have discovered that it is possible to obtain an additive based on sulfonated and chlorinated (neutralized) tar that can eliminate the conventional drawbacks and has better properties compared to conventional ones, This led to the present invention.

The first object of the present invention is to provide a fluidizing and stabilizing additive based on sulfonated and chlorinated tars.
Oxidation is confirmed by the generation of 802 during the sulfonation reaction, and the sulfonated tar is oxidized until the amount of SO2 evolved is from 2 to 60% by weight, preferably from 10 to 35% by weight with respect to the weight of the tar. The objective is to provide fluidizing and stabilizing additives.

In the description of the invention, "tar" refers to pits obtained by carbonization, for example in a coke oven, in particular at temperatures of 1100 °C or higher (a fraction of which has a boiling point of 100 to 350 °C). - Coal tar itself means the distillation residue of pit coal tar at 350 DEG C., other than the tar or tar fraction obtained in petroleum processing plants.

Whatever the tar, it must contain at least a small proportion of compounds with two or more fused aromatic rings.

A second object of the present invention is to provide a method for making the above-mentioned fluidizing and stabilizing additive. The method according to the invention includes the following steps.

6a) at least one solvent selected from halogenated organic solvents, inert to the sulfonation reaction and immiscible or poorly miscible with water, preferably with a boiling point of 30 to 130°C; The coal is slowly contacted with liquid or gaseous sulfur trioxide (preferably without removing the heat of reaction ) process.

b) Temperature 80 to 140°C, preferably 9o to 1
At 20°C, while detecting waste SO2,
2 generation amount is 2 to 60% by weight with respect to the weight of tar.
, preferably in the range of 10 to 35% by weight.
A process of carrying out a reaction between O3 and tar.

C) Neutralizing the solution of sulfonated and oxidized tar with a base, preferably an aqueous solution of sodium hydroxide or ammonium hydroxide, to pH 7 or pH 10.

d) removing the solvent of the solution or tar by decantation and/or evaporation.

e) recovering the aqueous solution containing the sulfonated, oxidized and neutralized additive. and f) condensing or drying the additive.

Steps C) and d) may be reversed.

According to a special embodiment of the process of the invention, the tar is first dissolved in at least one of said solvents, and in this tar solution sulfuric anhydride is added up to -1 or at least one of said solvents.
The species is introduced by dissolving it in a solvent (care must be taken to ensure that the solvents are mutually compatible, that is, they do not cause chemical reactions).

According to a second embodiment of the method according to the invention, tar (dissolved or undissolved in at least one of said solvents) is added to a solution of sulfur trioxide in at least one of said solvents. When incubating as a solution, use a compatible solvent and carry out the incubation very slowly to prevent too violent a reaction.

To further illustrate the present invention, several examples will be described, but these examples are not intended to limit the invention.

The tar used in the tests shown in each example is tar obtained from a coke oven, with a specific gravity of 1.1577.
9/Cm3 and viscosity 83.8] cst (40'C
).

Example I A neck flask equipped with a stirrer with PTFE blades, a thermometer, a water-cooled spherical bulb condenser, and a filling funnel (
A reactor consisting of >500 cc was used.

The flask was charged with 44.9 g of tar diluted with ethylene tetrachloride, 00 cc; and the filling funnel was filled with a solution containing 50,353 g of liquid in 1.00 cc of ethylene tetrachloride.

A solution of sulfur trioxide is introduced into the reaction flask over a period of approximately 2 hours, during which time the reaction flask is constantly cooled to bring the internal temperature to 1.
The temperature was maintained between 0 and 15°C.

At the end of the SO3 addition, the internal temperature was raised to 20-25°C and the reaction mixture was then heated to reflux temperature (approximately 120°C) for about 1 hour and maintained at this temperature for 1 hour.

The reaction mixture was then allowed to cool, diluted with water, and the resulting crude reaction product was transferred to a beaker and neutralized to pH 7 with aqueous NaOH. The whole is then distilled under atmospheric pressure,
The solvent was recovered as a water/ethylene tetrachloride azeotrope.

A solid-free aqueous solution of 975,j9 was obtained, and 196 CG of the 200 CG of solvent used was recovered.

N a 2 S O4 content 1.70
% dry active substance 107 g Sodium sulfate produced 16.6 g SO2 gas produced 2.1 g Example 2 The apparatus described in Example 1 was used.

Tar 43 diluted with 100 cc of carbon tetrachloride in a flask
50351.7 g diluted with 100 cc of carbon tetrachloride was put into the filling funnel.

A solution of SO3 was added in 2 hours and the reaction mixture was left at room temperature for 1 hour with external cooling with water (internal temperature 15-18°C) and then refluxed for 2 hours. ,,. --Uyugayayue.

The mixture was cooled, diluted with water, transferred to a beaker, and the flask was washed again with water and combined, and neutralized to pH 7 with an aqueous sodium hydroxide solution.

The azeotrope of carbon tetrachloride/water was distilled off as an overhead fraction to obtain 1176 g of an aqueous solution as a residue.

N a 2 SO4 content 1.7% dry active substance 94.59 Sodium sulfate produced 20 g SO□ gas produced 2.6 g Examples 3 to 17 The reactions of Examples 3 to 17 were carried out at different temperatures and solvents depending on the tar and SO3 The dilution of the tar and the time of addition of SO3 to the tar were carried out under the same conditions.

Reactor: Same as Example 1. Tetrachlorethylene (TCE) 100 CO in a flask
Pour the tar diluted with TCE 100 into the funnel.
SO2 diluted with CG was introduced.

Addition of the SO3 solution took place in about 90 minutes, during which time the reaction flask was externally cooled with water (internal temperature 10-15°C).

The entire reaction mixture is then brought to room temperature (approximately 20-30'C).
K was maintained for 1 hour and further refluxed at 120°C for 1 hour. The reaction mixture was cooled to room temperature, diluted with water and then hydroxylated.l) Neutralized with aqueous rum solution. After neutralization, much of the solvent was separated as the lower layer of the resulting reaction mixture and the majority was recovered as an azeotrope with water. Solvent recovery was approximately 96% to 97%.

The data related to these tests are shown in the table below.

In the °C deviation example, the gas generated (mainly consisting of SO2 with trace amounts of SO3) was analyzed by absorbing it downstream of the condenser in the mélange containing the titrated aqueous NaOH solution. .

Example 18 The equipment is the same as described in Example 1.

Filling in the reaction flask: 50380 g diluted with TCE 100 CC: Filling in the dropping funnel: 44 g tar diluted with TCE The tar solution was added to the SO3 solution over about 50 minutes.

During this time, the reaction temperature gradually increased from 22°C to 72°C. The reaction mixture was then heated to 120°C'! , and the temperature was maintained at this value for 1 hour. Much of the solvent was tedecantated at 80°C. The flask was then immersed in a constant temperature bath at 140°C.

Most of the solvent was recovered in 80 minutes (recovery rate approximately 98%)
. While still hot (80-85 °C), the reaction mixture was
The mixture was neutralized to pH 7 with aqueous NaOH solution and diluted with water.

795 g of aqueous solution was obtained.

Sodium sulfate content 2.9 Dry active substance 92.9% sodium sulfate
23.1 g 50213 g organic sulfur generated during the reaction 14.3 g Example 19 The apparatus is the same as in Example 1.

Filling in the flask: 44 g tar diluted with 326 g TCE Filling in the dropping funnel: 50381 g liquid The addition of liquid SO3 to the tar solution was carried out in 40 minutes without external cooling of the reaction flask. The temperature was initially 23°C, rose to a peak value of about 90°C, and reached 65°C at the end of the addition.

The reaction mixture was heated to 20° C. for 15 minutes and maintained at this temperature for 1 hour.

274 g of TCE, which was then recovered by decantation of the solvent at approximately 90°C, was added to the reaction flask at 13°C.
2 to 134°C, and the solvent was removed by distillation. Through this secondary operation, the remaining TC
E was recovered.

The residual mixture was diluted with NaOH at about 80-90°C.
It was neutralized to pH 7 with an aqueous solution. 477 g of an aqueous solution of sulfonated, oxidized and chlorinated tars were obtained.

Na 2 So 4 content 6.8 ji Dry active substance 97.5 ji Sodium sulfate 32.4 g 5o21 generated
3.9 g Organic sulfur 17.1 g Example 20 The equipment is the same as in Example 1.

Filling in the reaction flask: 44 g tar diluted with 327 g TCE Filling in the dropping funnel: 80379 g liquid Liquid SO3 was added to the tar over a period of 40 minutes while cooling the reaction flask externally. The temperature was initially 21°C and rose to a peak value of 90°C, and the addition (8a, &i
65°. Yes, yes.

The reaction mixture was heated to the boiling temperature of TCE (approximately 120° C.) for 15 minutes and maintained at this temperature for 1 hour.

The bulk of the solvent (270, pi') was then decanted at about 85°C and the reaction flask was immersed in a constant temperature oil bath at 140°C. The remaining solvent was collected in 2 hours. In the flask, the solid residue was neutralized to pH 7 with aqueous sodium hydroxide.

Volume of final aqueous solution 474.4, j9 Sodium sulfate content 7.4 Dry active substance 93.9 g Sodium sulfate
35.19 802 occurred during test
13.1 g organic sulfur 15.
4 ji Comparative Example 1 The apparatus is the same as described in Example 1.

The flask was filled with 38.8 g of tar diluted with 200 cc of ethylene tetrachloride, and the filling funnel was filled with liquid 5034.
I entered 3.89. The latter was added dropwise to the reaction flask over a period of approximately 80 minutes, during which time the internal temperature was constantly maintained at 17-20° C. by external cooling with circulating water. The reaction mixture was then allowed to stir for a further 4 hours, again maintaining an internal temperature of approximately 17°C. The sulfonated tar mixture was then neutralized to pH 7 with an aqueous sodium hydroxide solution.

It was recovered by azeotropic distillation using a solvent.

An aqueous solution of 897.3 ji was obtained.

Sodium sulfate content 3.82 Dry active substance 63.99 Sodium sulfate 34.3 g SO2 evolved Below analytical limit Organic sulfur 9.2 g The product thus obtained has no dispersing properties.

Comparative Example 2 The reaction apparatus used was a reaction flask of so and o ccQ.
It is the same as that described in Example 1, except that it is a 250CG instead of a 250CG.

For the reaction, put 17.0 g of tar diluted with 50 CC of TCE in a flask, and add TCE to the filling funnel.
331.8 g of 5o3 diluted with 50CC: was added.

The latter was added to the reaction flask at about 135 °C while maintaining the internal temperature between 16 °C and 18 °C by external cooling with flowing water.
Installed in minutes. The mixture was then stirred for an additional 130 minutes, maintaining the temperature at approximately 18°C at all times.

Thereafter, the reaction mixture was neutralized to pH 7 with an aqueous sodium hydroxide solution.

Aqueous solution of sulfonated tar sodium salt 787.49'
' ? ! ';v, +1-tx・
A Sodium sulfate content 1.4
5xi dry active substance 58.6 g Sodium sulfate 11.4 g 8 generated during the reaction
02 Organic sulfur below analytical limit
9.4 g The product obtained shows no dispersion properties.

Viscosity measurement of water/coal dispersions To evaluate various dispersant samples (according to the invention and commercially available), an MVI sensor and an M50
Rotational viscometer Haake RV with 0 measuring head
Measurements of viscosity were carried out at different velocity gradients according to No. 12.

For this purpose, in a beaker (zoocc) coal of particle size <60 mesh and moisture content <o, 5%
0.9 was weighed and the aqueous mixture of the dispersant to be considered was added from 1 to the following composition.

Coal 70 (wt%) Water
29.5 Dispersant 0.5 Each product was mixed with a stirrer for 1 minute at 650 rpm, followed by 2 minutes at 1200 rpm. The resulting suspension was introduced into the external measuring cylinder of the viscometer, which had already been isothermalized to 20°C, and after being left at 20°C for 15 minutes, various velocity gradients (r) (3, 8 to about 1 sost
The shear stress (τ) at ) was measured. The measurements obtained in this way were inserted into the Ostwald formula for pseudoplastic behavior.

For each set of i measurements (τ-γ), the values of K and n and the curve (τ-'r) were calculated with linear regression. In addition, the "asymptotic" viscosity ηasympt was calculated for the last five tests. Note that τ−
A rho measurement was performed using a meter.

The values obtained by looking at some samples as described above are as follows.

Determination of Resistance to Shear Stress Samples of the dispersant according to the invention were tested for "stability as a function of shear stress" according to the following method: a commercially available sample (DAXAD15, Grace Italia)
Company).

336 g of dry coal (moisture <0.5%) with a particle size of 60 mesh and an aqueous solution of a dispersant were introduced into a glass reactor (11) with a height of 10 CnL and a diameter of about 10 with 7 flanges. The composition was

Coal 70 (weight 2) H2O29.5 Dispersant 0.5 With the reactor open to the atmosphere, stir at 650 r with a stirrer.
The mixture was allowed to stir for 2 minutes at pm and 10 minutes at 120''Or'pm.

The flange was closed and a stirring blade with a flywheel of 2 mm diameter was installed at a level of 200 m1, and the mixture was
Stirring was maintained for 24 hours at Orpm.

After that, the stirring was stopped, the stirring blade was removed, and the mixture was
It was left undisturbed for a day. Thereafter, the beaker was tilted and the sludge was discharged.

The condition at the time of discharge was evaluated as follows, and the results are shown in the table below.

-K If all the sludge flows out at the same time -x-z
Penalty: 0 - If the residue left on the bottom can be easily re-fluidized with a glass rod or simple tool - If a dense deposit forms on the bottom that cannot be easily removed with a spatula.

Claims (1)

[Scope of Claims] 1. In a fluidizing and stabilizing additive based on sulfonated and chlorinated tar, the oxidation is confirmed by the generation of SO_2 during the sulfonation reaction, and the sulfonated tar is A fluidizing and stabilizing additive obtained by oxidizing SO_2 to an amount of 2 to 60% by weight relative to the weight of tar. 2. In the additive according to claim 1, the SO
Fluidizing and stabilizing additive, in which the amount of _2 generated is from 10 to 35% by weight with respect to the weight of the tar. 3. In the process of producing a fluidizing and stabilizing additive based on sulfonated, chlorinated tars, a) selected from halogenated organic solvents, inert to the sulfonation reaction, and free from water. b) slowly contacting the coal with liquid or gaseous sulfur trioxide in the presence of at least one solvent that is immiscible with water or poorly miscible with water; While detecting, the reaction between SO_3 and the tar is carried out until the amount of SO_2 generated is in the range of 2 to 60% by weight based on the weight of the tar, and c) the solution of the sulfonated and oxidized tar is treated with an alkaline agent. d) removing the tar solvent by decantation and/or evaporation (although the order of steps c) and d) may be reversed); e) dissolving the sulfonated, oxidized and chlorinated and f) concentrating or drying the additive. 4. A method for producing a fluidizing and stabilizing additive according to claim 3, wherein the solvent has a boiling point of 30 to 130°C. 5. The method for producing a fluidizing and stabilizing additive according to claim 3, wherein the solvent is selected from carbon tetrachloride, ethylene tetrachloride, and dichloroethane. 6 In the manufacturing method described in claim 3, SO_
A process for the preparation of a fluidizing and stabilizing additive, in which the amount of 2 generated is from 10 to 35% by weight with respect to the weight of tar. 7. A method for producing a fluidizing and stabilizing additive according to claim 3, wherein the neutralization is carried out using a sodium hydroxide solution. 8. A method for producing a fluidizing and stabilizing additive according to claim 3, wherein the neutralization is carried out using an ammonium hydroxide solution. 9. A method for producing a fluidizing and stabilizing additive according to any one of claims 3, 7, and 8, wherein the neutralization is carried out until the pH reaches 7. 10. A method for producing a fluidizing and stabilizing additive according to claim 9, wherein the neutralization is carried out until the pH reaches 10. 11 In the manufacturing method according to claim 3, tar is dissolved in at least one solvent, and in this solution,
A process for the preparation of a fluidizing and stabilizing additive in which sulfur trioxide is brought into contact with tar by introducing the sulfur trioxide neat or dissolved in at least one solvent. 12 In the manufacturing method described in claim 3, tar is converted into sulfur trioxide by adding the tar as it is or dissolved in at least one solvent to a sulfur trioxide solution in at least one solvent. A method of making a fluidizing and stabilizing additive by contacting it with a fluidizing and stabilizing additive.