DE3519115A1 - LIQUIDATION AND STABILIZATION ADDITIVE FOR SOLID SUSPENSIONS AND METHOD FOR THE PRODUCTION THEREOF - Google Patents

Description

PATENT attorney dr.-inc. franz wuesthofp

WUESTHOFF- v. PECHMaNN -BEHRENS-GOHTZ D «.« M.FREDAwuESTHo "

DlPL.-ING. GERHARD PULS (19J2-I971)

EUROPEAN PATENTATTORNEYS ^ D1J-L.-CHEM.DR.EP _R E1LORD VON PECHMANN

DR.-1NG. DIETER BEHRENS DIPL.-ING. DIPL.-WIRTSCH.-INC. RUPERT GOETZ

D-8000 MUNICH 90

., ._ SCHWIiKM-RSI KASSI 2

Ia I ID phone: (089) 6620 ji

TELEGRAM! PROTECT PATENT TELEX: J 24070

fax: via (089) 271 6063 (111)

description

Liquefaction and stabilization additive for solids suspensions and process for its preparation

The invention relates to a liquefaction and Stabilization additive as well as on the ancestor of srinor Manufacturing.

In particular, the invention relates to an additive for liquefying and stabilizing of suspensions of solids in liquids, especially of coal in liquids and especially in water, as well each on the process for producing the additive. More particularly, the invention relates to a liquefying and stabilizing additive for highly concentrated Coal suspensions in water, i.e. for suspensions with a concentration of more than 60% by weight, in particular from 70 to 80% by weight or more, as well as the method for producing the additive.

The following description refers to the specific Reference is made to the case of the coal / water suspensions; the invention Of course, additive can be used wherever there are problems with liquefaction and stabilization due to the presence of suspended solids.

/ 2

There are liquefying and stabilizing additives for Aqueous coal suspensions known, the compounds of sulfonated and neutralized with salt formation Tars exist, the sulfonated compounds concentrated by the action of anhydrous or fuming Sulfuric acid can be obtained on tar or tar materials. These known sulfonated additives suffer from this Disadvantage that they contain large amounts of alkali or ammonium sulfates, which when neutralizing the sulfuric acid solution, which contains the sulfonated tar products, arise with alkali or ammonium hydroxides.

In order to sulfonate all of the tar, sulfuric acid must be in the Excess are used and the alkali or ammonium sulfates remain within the sulfonated and neutralized tar products when the water with which the neutralizing agent have been supplied, has been removed.

A second disadvantage of the known additives is that they at least partially condense with formaldehyde must be in order to achieve better viscosity properties and that an additional one in the production and very expensive stage is required.

It has surprisingly been found that the disadvantages of the prior art can be overcome with the aid an additive based on sulfonated tar converted into salt form, which has better properties

30 points as the known additives.

The invention relates to a liquefying and stabilizing additive on the basis of sulfonated! and tar converted into salt form, characterized in that that the sulfonated tar, which has been converted into the salt form, or the tar compound has been oxidized; the oxidation is

/ 3

recognizable by the development of SO- during the sulfonation stage and the amount of SO- released is in the range from 2 to 60% by weight of the tar used, preferably in the range from 10 to 35% by weight. 5

Tar in the sense of the description is coal tar as such, as it is obtained, for example, in coke ovens, in particular by the distillation or coking of coal at 1100 ^° C. or above; Tar fractions having boiling points in the range of 100 to 350 ⁰ C. in question continue the residue coming coal tar distillation at 350 ⁰ C and tar or tar fractions, the processing in petroleum plants are obtained.

Regardless of its origin, the tar must have at least one contain a small percentage of compounds with more than two aromatic condensed rings.

The invention also relates to the process for producing the liquefaction and liquefaction described above Stabilizing additive. The method according to the invention comprises the following stages:

1) Bringing them into contact slowly (preferably without dissipating the heat of reaction)

of tar with liquid or gaseous sulfuric anhydride in the presence of one or more solvents for tar, selected from the class of halogenated organic compounds that are inert with respect to the sulfonation reaction, are immiscible or only slightly miscible with water and are preferably selected from the compounds of which Boiling point in the range from 30 to 130 ^° C., in particular carbon tetrachloride, tetrachlorethylene and dichloroethane;

2) Ignition of the reaction between SO- and tar

a temperature in the range from 80 to 140 ⁰ C, preferably from 90 to 120 ⁰ C, monitoring the SO ₂ development,

/ 4

- £ ~ 3519t15

until it reaches a value in the range from 2 to 60% by weight, preferably from 10 to 35% by weight on the weight of the tar fed;

3) neutralizing the solution from sulfonated! and oxi-

dated tar with aqueous solutions of alkaline substances, preferably sodium hydroxide or Ammonium hydroxide until a pH of 7 or even 10 has been reached;

4) separating the solvent or solvents for the tar by decanting and / or evaporation;

5) recovery or isolation of the aqueous solution which salified the sulfonated and contains oxidized additive;

6) Concentration or concentration or, if necessary, drying of the additive.

Steps 3) and 4) can be carried out in any order.

According to a particular embodiment of the invention In the process, the tar can first be dissolved in one or more of the solvents mentioned and the liquid or gaseous sulfuric anhydride can be introduced as such into the tar solution or also dissolved in one or more of the solvents mentioned, with the only proviso that the solvents must be compatible with one another, i.e. not enter into or cause any chemical reactions.

According to a second particular embodiment of the invention Process can be dissolved or not dissolved in one or more of the solvents mentioned in a solution of sulfur trioxide in one or more of the solvents mentioned are poured, with im If it is poured in as a solution, care must be taken that the solvents are compatible with one another and that pouring is very slow in order to avoid a violent reaction.

Some examples will now be given to better illustrate the invention; it can be assumed that the Invention is in no way limited by these examples.

The tar employed in all runs of the examples was a coke oven tar having a specific gravity of 1.1577 g / ml and a viscosity of 83.81 mm '/ s (cSt) at 40 ⁰ C.

10

example 1

The device consisted of a 500 ml 4-neck flask equipped with a mechanical stirrer with PTFE (polytetrafluoroethylene) Leaves, a thermometer, a water-cooled ball cooler and a feed funnel .

In the flask was 44 g of tar diluted with 100 ml of tetrachlorethylene abandoned and in the funnel a solution of 53 g of liquid SO ^. in 100 ml of tetrachlorethylene poured.

The sulfur trioxide solution was in the course of about two Hours dripped into the reaction flask, its internal temperature was kept in the range of 10 to 15 ° C by continuous cooling.

At the end of SO., Addition allowing the internal temperature to 20 to 25 ° C and rise about an hour later the reaction mixture to reflux temperature (about 120 ⁰ C) and held for one hour at this temperature.

The reaction mixture was then cooled, diluted with water and the resulting crude reaction product in a Beaker transferred and neutralized there with sodium hydroxide solution to pH 7. It was then under atmospheric pressure

/ 6

distilled and the solvent recovered as an azeotropic mixture of water and tetrachlorethylene.

It was a solids-free aqueous solution in a Amount of 975 g obtained and 196 ml of the original 200 ml solvent recovered.

Na SO content 1.70%

dry active substance 107 g

10 sodium sulfate resulted in 16.6 g

SO- created 2.1 g

Example 2

The device according to Example 1 was used. 15th

43 g of tar, diluted with 100 ml of carbon tetrachloride, were placed in the flask. abandoned and in the funnel 51.7 g SO-., diluted with 100 ml carbon tetrachloride.

The SO solution was run in over the course of two hours while the flask was cooled externally with water (internal temperature 15 to 18 ° C.). The reaction mixture was then left for one hour at room temperature and then in the course of two hours under reflux (about 80 ⁰ C.). The reaction mixture was cooled to room temperature, diluted with water, transferred to a beaker and the flask was washed again with water and then neutralized to pH 7 with sodium hydroxide solution (aqueous sodium hydroxide solution).

The azeotropic mixture of carbon tetrachloride and water was distilled off as the top fraction; 1176 g of aqueous solution remained.
Na ₂ SO ₄ content 1.7%

35 dry active substance 94.5 g

Sodium sulfate resulted in 20 g

S0_ resulted 2.6 g

/ 7

AO

Examples 3 to 17

Examples 3 to 17 were carried out under the same experimental conditions with regard to temperature, dilution of the Tar and from SO-. with solvent and addition time for SO carried out. The device was the same as in Example 1 .

Course of the reaction: tar, diluted with 100 ml of tetrachlorethylene (TCE), was placed in the flask and placed in the feed funnel SO, diluted with another 100 ml of TCE.

The SO, solution was added in the lead of about 00 min, cooling was carried out with water from the outside (internal temperature 10 to 15 ° C.).

The reaction mixture was then held for about one hour at room temperature (about 20 to 30 ⁰ C) and then heated under reflux for one hour at 120 ⁰ C. The reaction mixture was cooled to room temperature, diluted with water and then neutralized with sodium hydroxide solution. Most of the solvent was separated as the lower phase in the reaction mixture obtained after neutralization and partially recovered as an azeotropic mixture with water. In total were about

25 96 to 97% of the solvent recovered.

The individual data from these tests are listed in the table.

The exhaust gases (mainly SO and some traces of SO,) were analyzed in all examples by means of absorption in a trap connected downstream of the cooler, which titrated a contained aqueous NaOH solution.

35 Example 18

The device was the same as in Example 1.

/8th

_ * _ 3519Π5

Receipt in the reaction flask: 80 g SO ₃ , diluted with 100 ml

TCE.

Submission in the dropping funnel: 44 g tar, diluted with TCE.

The tar solution was added to the SO ^ solution over about 50 minutes while the temperature of the reaction mixture rose from 22 to 72 ° C. The reaction mixture was then ^{heated to 120 °} C. and this temperature was maintained for one hour. The main part of the solvent then separated by settling at 8O ⁰ C. The flask was immersed in it, a held by a thermostat at 140 ⁰ C bath.

Most of the solvent was recovered (about 98%) over 80 minutes. The reaction mixture was neutralized while still hot (80 to 85 ° C) up to pH 7 with 15 L sodium hydroxide solution and then with water diluted.

795 g of aqueous solution were obtained.
20 Na ₂ SO content 2.9%

active substance dry weight 92.9 g sodium sulfate (formed) 23.1 g

SO ~ released during the reaction 13 g
organic sulfur 14.3 g

Example 19

Device as in example 1.

Submission in the flask: 44 g tar, diluted with 326 g TCE.

Submission in the dropping funnel: 81 g of liquid SO.,.

The addition of the liquid SO. To the tar solution took place over the course of 40 minutes, without external cooling of the reaction flask. (The temperature, originally 23 ° C, rose to a peak value of 90 ⁰ C and was at the end of the addition, 65 ° C).

^{The reaction mixture was heated to 120 °} C. in the course of 15 min and kept at this temperature for one hour.

Thereupon the solvent was eliminated by settling at about 9O ⁰ C. (recovered 274 g of TCE) T, the reaction flask was then immersed in a held by a thermostat at 132 to 134 ° C oil bath to distill off the solvent. This recovered the remaining TCE. The mixture that remained was ^{neutralized at about 80 to 90 °} C. with sodium hydroxide solution up to pH 7. The weight of the aqueous solution of sulfonated-oxidized tar converted into the salt form, obtained as the end product: 477 g.

Na ₂ SO ₄ content 6.8%

active substance, dry weight 97.5 g

Sodium sulfate 32.4 g

15 SO ₂ released 13.9 g

organic sulfur 17.1 g

Example 20

Device as in example 1.

Submission in the reaction flask: 44 g tar, diluted with 327 g TCE.
Submission in the dropping funnel: 79 g of liquid SO ₃ .

The liquid SO ~ was added over 40 min to the tar solution, without external cooling of the reaction flask (internal temperature initially 21 ⁰ C, increase to 90 ⁰ C and at the end of the SO -.- adding 65 ° C).

The reaction mixture was then heated in the course of 15 min to the TCE boiling temperature (about 120 ^° C.) and this temperature was maintained for one hour. Most of the solvent (270 g) separated out by allowing it to settle at about 85 ° C; the reaction flask was then ^{immersed in a bath kept thermostatically at 140 °} C. and the remaining solvent was distilled off within two hours. The solid residue in the flask was

/ 10

neutralized with sodium hydroxide solution up to pH 7.

Weight of the final product obtained
aqueous solution 474.4 g

Na SO content 7.4%

active substance, dry weight 93.9 g

Sodium sulfate 35.1 g

S0_ released in the course of the experiment 13.1 g organic sulfur 15.4 g

Comparative example 1

Device as described in Example 1.
Course of reaction. 38.8 g of tar, diluted with 200 ml of tetrachlorethylene, were placed in the flask and added to the

15 addition funnel 43.8 g of liquid SO.,. This was introduced over about 80 min dropwise to the reaction flask was externally cooled with running water, so that the inner temperature was 17 to 20 ⁰ C.
The mixture was then stirred for a further 4 hours and the

The internal temperature was kept in the range of 17 ° C. The mixture of sulfonated tar was then washed with caustic soda neutralized up to pH 7.

The solvent was then azeotroped
25 distillation recovered.

897.3 aqueous solution were obtained.

Sodium sulfate content 3.82%

active substance, dry weight 63.9 g
Sodium sulfate 34.3 g

SO- released analytically not

more detectable organic sulfur 9.2 g

35 The product thus obtained had no dispersing properties.

Comparative example 2

Device as described in example 1 with the modification, that a 250 ml flask was used instead of a 500 ml flask.

Course of the reaction: 17.0 g of tar were diluted into the flask with 50 ml TCE, abandoned.

In the funnel were 31.8 g SO ,, diluted with 50 ml TCE, given.

The SO ^ solution was in the course of about 135 minutes Reaction flask added dropwise, while cooling from the outside with flowing Water so that the internal temperature was kept in the range of 16-18 ° C. The mixture was subsequently Stirred at a temperature of about 18 ° C. for a further 130 min.

The reaction mixture was then neutralized to pH 7 with sodium hydroxide solution.

There were 787.4 g of an aqueous solution of the sodium salt of sulfonated Obtain tar.

Sodium sulphate content 1/45%

active substance, dry weight 58.6 g sodium sulfate 11.4 g

SO », not released analytically during the reaction

verifiable

organic sulfur 9.4 g

The product thus obtained had no dispersing properties.

Viscosity measurements of water / carbon dispersions In order to evaluate the various dispersant samples (both described here and commercially available), viscosity measurements at different speed gradients were carried out using a Haake RV12 rotational viscometer equipped with an MVI sensor and an M500 measuring head

carried out.

/ 12

For this purpose, 70 g of coal with a grain size of -C250 μm and with a moisture content of less than 0.5% weighed into a 200 ml beaker and then with an aqueous Mixture of the dispersing agent that was to be tested was added so that the total was:

70 wt% coal 29.5 wt% water 0.5 wt% dispersant.

The whole was stirred with a stirrer with two metal arms for 1 minute at 650 rpm and for 2 minutes at 1200 rpm. The resulting suspension was introduced into the outer graduated cylinder of the viscometer which had already been brought isothermally at 20 ⁰ C and after a residence time of 15 min at 20 ⁰ C, the values of the shear stress (X) at various velocity gradients (γ) of 3, 8 to about 150 s). The experimental values were determined using Ostwald's equation

Ύ = Κ.ϊ,

which is valid for pseudoplastic behavior, evaluated,

For each series of experimental measurements "f-γ, the values of K and η and the curve _ter -Ύ were calculated with linear regression. Furthermore, for the last five tested γ-values (γ = 37, 60, 75, 120 and about 150 s " ¹ ) the values of the asymptotic viscosity η are calculated, for which the correction of the experimental data fY is necessary.

The values obtained in this way for some samples are as follows:

Dispersing (commercial 0 n K • S "asympt .S middle product , 91 Pa 83 Pa 58 DAXAD 15 18th 0 0, 0, usual 1 1 0 , 92 81 61 example , 87 0, 05 0, 57 example 1, 0,

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Measurements of resistance to shear stress (shear stress)

A sample of the dispersant according to the invention was compared with the sample of a commercial dispersant (DAXAD 15, Grace Italy), according to the procedure described below, which is referred to as "stability as a function of shear stresses".

Into a 1 liter glass reactor with flange, height and diameter 10 cm each, 336 g of dry (moisture <0.5%) coal in one grain size <250 μτη given, and a solution of the dispersant in water, so that one finally had a template which consisted of 70 wt .-% coal, 29.5 wt .-% H-O and 0.5 wt .-% of the dispersant duration.

With the reactor open, the mixture was first stirred at 650 rpm for 2 minutes and then at 1200 rpm for 10 minutes touched.

The flange was closed, at the height of 200 ml there was an impeller with an impeller of 2 cm diameter arranged and the mixture stirred for 24 hours at 200 rpm. Then the impeller was removed and that Left for three whole days. After this time, the beaker was tilted and the sludge poured off

The results obtained are given in the table below with the help of the following symbols: * = all the sludge flows spontaneously

** = the residue remaining on the floor can be easily removed with the help of a glass rod or similar tool liquefy again

*** = a compact precipitate has formed on the ground, which can be removed with a spatula or similar

Tool cannot be easily removed.

/ 14

3519T15

(1 5) money Additive 24 water Conc. Of Casting 1 1 G solution 36.92 G active behavior 336 G 120 substance 336 107.08 in the * * Additive additive solution ^% DAXAD 10.0 Ex. 6.5

/ 15

Tabel

Tests with different SO_VTeer weight ratios

Well-SO. SO ₀

2 4 2 orga- / tar

active substance ent- entic 3

Ex. Tar SO. The dry weight was the sulfur weight ratio

g g g g g g

3 41.5 17 48.8 4.2 1.3 5.4 0.41

U 41.5 26 55.0 7.7 2.4 7.4 0.63

5 40.3 31 62.6 7.5 2.7 8.5 0.77

6 40 36.7 53.5 8.2 2.9 7.7 0.92

7 40.1 45.7 75.1 14.8 3.2 10.6 1.14

8 40.2 51.5 80.8 18.3 * », 0 12.6 1.28 oo

9 40.2 62.6 89.5 19.9 4.2 15.3 1.56

10 40 66.4 90.9 24.8 5.0 15.4 1.66

11 41.7 69.5 97.1 25.4 5.8 18.2 1.67

12 43 75 98.7 28.6 9.0 16.9 1.74

13 37 69.8 87.3 27.7 11.2 14.8 1.89

14 40.4 83.6 97.8 35.3 13.7 15.6 2.07 <£

15 32.7 89 93.0 50.7 13.7 16.5 2.72 ^

16 26 81.6 74.6 53.7 12.7 12.6 3.14 - +

17 30.6 102.7 93.0 71.7 16.9 16.6 3.36 <*

Claims (12)

PATENT LAWYERS dr.-inc. franz tuesthofp WUESTHOFF-v.PECHMANN -BEHRENS-GOjEXZ ">« ■ "" «■ ·" «> * wuesthof, DIPL.-ING. GERHARD PULS (19JJ-1971) EUROPEAN PATENTATTORNEYS d.pl.-chem. dr. ε. Mr. von Pechmann DR.-1NG. DIETER BEHRENS DIPL.-1NG. DIPL.-VIRTSCH.-ING. RUPERT GOET! 19 Tt R D-8000 MÜNCHEN 90 IC7.1 IO SCHWEIGERSTRASSE 2 phone: (089) 66 20 51 telegram: protectpatent TELEX: 5 24070 fax: via (089) 271 6063 (111) patent claims 1. Liquefaction and stabilization additive on the Base of sulfonated and salted Tar, characterized in that sulfonated tar / tar converted into salt form has been oxidized, wherein the oxidation has been detected by the release of SO- during the sulfonation reaction and the Amount of released SO- in the range from 2 to 60 wt .-%, based on the tar. 2. Additive according to claim 1, characterized in that S0 "in an amount of 10 to 35 wt .-%, based on the tar that has been released. 3. A method for producing the additive according to any one of the preceding claims, characterized in chn gekennzei e t that it comprises the following stages: a) Slowly bringing coal into contact with liquid or gaseous sulfur trioxide in the presence of one or more solvents for tar selected from the class of halogenated organic compounds that are inert and with respect to the sulfonation reaction are not or only slightly miscible with water; b) termination of the reaction between SO and tar at a temperature in the range from 80 to 140 ^° C., preferably from 90 to 120 ^° C., with monitoring of the release of SO _? up to a value in the range from 2 to 60% by weight, / 2 based on the tar * c) neutralizing the sulfonated and oxidized solution Tar with aqueous solutions of alkaline agents; d) removal of the solvent (s) for the tar by settling and / or evaporation; e) Obtaining the aqueous solution containing the sulfonated and salt form and oxidized additive contains dissolved; f) concentration or, if necessary, drying of the additive, wherein steps (c) and (d) are in any order can be executed. 4. The method according to claim 3, characterized in that the solvent has a boiling point 15 have in the range from 30 to 130 ⁰ C. 5. The method according to claim 3 or 4, characterized in that the solvents under carbon tetrachloride, Tetrachlorethylene and dichloroethane 20 can be chosen. 6. The method according to any one of claims 3 to 5, characterized in that SO in an amount from 10 to 35 wt .-%, based on the tar, released 25 will. 7. The method according to any one of claims 3 to 6, characterized in that the neutralization with a sodium hydroxide solution. 8. The method according to claim 3 to 6, characterized in that the neutralization with an ammonium hydroxide solution is made. 9. The method according to any one of claims 3 to 8, characterized in that up to a pH value is neutralized by at least 7. / 3 10. The method according to claim 9, characterized in that up to a pH value of 10 is neutralized will. 11. The method according to any one of claims 3 to 10, characterized characterized in that the tar is previously dissolved in one or more of the solvents and Sulfur trioxide is brought into contact with the tar, in which it is entered as such or dissolved in one or more d <M liüsunqsm i I t c * 1 in the Torr .1 öswruj. 12. The method according to any one of claims 3 to 10, characterized characterized in that the tar is brought into contact with sulfur trioxide by the tar either as such or dissolved in one or more of the solvents in a solution of sulfur trioxide in one or more of the solvents is poured in. 7234