CA1328143C - Dispersant for aqueous slurry of carbonaceous solid - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE
This invention discloses a dispersant for an aqueous carbonaceous solid slurry, which comprises a water-soluble copolymer having an average molecular weight of 1,000 to 500,000 and obtained by polymerizing (A) 0.1 to 7 mol% of a polyalkylene glycol mono(meth)acrylate type monomer, (B) 5 to 94.9 mol% of a sulfoalkyl (meth)acrylate type monomer, (C) 5 to 94.9 mol% of an unsaturated carboxylic acid type monomer, and (D) 0 to 20 mol% of other monomer (providing that the total amount of the monomers is 100 mol%) and/or a salt of the water-soluble copolymer.

Description

132~143 DISPERSANT FOR AQUEOUS SLURRY OF C~RBONACEOUS SOLID

F~ELD OF INVENTION
. .
This invention relates to a dispersant for the aqueous slurry of a carbonaceous solid. More particularly, it relates to a dispersant for effecting dispersion of a carbonaceous solid in water thereby producing an aqueous carbonaceous solid slurry composition possessing flo~ability even in highly concentrated state.
PRIOR ART
The pertroleum which has been heretofore in extensive use as an energy source is now suffering a notable rise of price and threatening exhaustion of deposit. In the circumstance, the development of some other energy source capable of stable supply has constituted itself a task to be imposed on the industry. Studies are now under way for the development of techniques for effective use of such carbonaceous solids as coal, oil coke, and petroleum pitch.
As actual means for effective use of such carbonaceous solids, thermal decomposition, gasification, combustion, substitution for heavy oil blown into blast furnaces in the steel-making industry, and substitution for heavy oil used in kilns in the cement industry, for example, are conceivable. In these techniques for effective use of carbonaceous solids, since the carbonaceous solids are in a solid state at normal room temperature, they are handled only with difficulty. These carbonaceous solids are not easily used effectively as desired because they have the disadvantage that the fine particles crumbling from these solids are drifted in wind to pollute the environment and threaten dust explosion. The desirability of converting these carbonaceous solids into liquids thereby ensuring ease of handling and precluding environmental pollution and dust explosion is finding growing recognition. Further for the purpose of lowering the cost of transportation, it is desirable to convert these carbonaceous solids into liquids.~

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``` ^` 1 328 1 43 For the purpose mentioned above, the conversion of a carbonaceous solid into a slurry proves to be a desirable way of ensuring effective use of the carbonaceous solid.
For this slurry to be utilized for thermal decomposition, gasification, combustion, substitution for heavy oil to be blown into blast furnaces, and substitution for heavy oil to be used in kilns for cement production, it must be prepared in a highly concentrated form and, at the same time, must be prevented from inducing the phenomenon of solid-liquid separation due to sedimentation of solid particles suspended in the slurry.
In recent years, as means for converting a carbonaceous solid into a slurry, the method which effects this conversion by causing the carbonaceous solid to be dispersed in a medium such as water, methanol, or a fuel oil, has been proposed. To cite a typical example, the COM
(coal-oil mixture) which can be transported through a pipeline is verging on practical use. Since a fuel oil is used in the COM, it still has room for some anxiety about stability of supply and price. To avoid the difficulty, a highly concentrated aqueous slurry of a carbonaceous solid, in which water is used as an inexpensive and readily available medium, is attracting keen attention as a highly promising approach to the effective use of carbonaceous solids.
An attempt at increasing the concentration of a carbonaceous solid in the aqueous carbonaceous solid slurry ` by the known method, however, results in a notable increase of the viscosity and loss of the flowability of the slurry.
Conversely, a decrease of the concentration of the carbonaceous solid in the slurry results in a decline as in the efficiency of transportation and the efficiency of combustion. Further when the aqueous carbonaceous solid slurry of a lowered solid concentration i5 put to use in j applications which require removal of excess water, the treatments for the removal of water from the slurry and the .
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desiccation of the remaining cake call for an unduly larye expense and entail the problem of environmental pollution.
Heretofore, for the solution of the various problems mentioned above, various dispersants for aqueous carbonaceous solid slurries have been proposed. Typical examples of such dispersants include such surfactants and water-soluble polymers as sodium oleate (U.S. Patent No.

2,128,913~, polyoxyethylene alkylphenyl ether (U.S. Patent No. 4,094,810), stearylamine hydrochloride (U.S. Patent No.
2,899,392), polyethylene oxide (U.S. Patent No. 4,242,098), cellulose (U.S. Patent No. 4,242,09~), polysodium acrylate (U.S. Patent No. 4l217,109), sodium lignosulfonate (U.S.
Patent No. 4,104,035), formalin condensate of alkylphenol alkylene oxide adduct (Japanese Patent Laid-Open SHO
59(1984)-36,537), and formalin condensate of sodium naphthalenesulfonate (Japanese Patent Laid~Open SHO
56(1981)-21,636). These dispersants, however, are invariably deficient in practicability because the aqueous carbonaceous solid slurries produced by incorporation thereof ha~e no sufficient flowability and because such slurries necessitate incorporation of dispersants in unduly large amounts and prove uneconomical.
SIJ~ARY OF ~HE INVENTION
; This invention, therefore, provides a novel dispersant for an aqueous carbonaceous solid slurry.
This invention also provides a dispersant for easy preparation of an aqueous carbonaceous solid slurry possessing flowability even in a highly concentrated state.
This invention provides a dispersant for an aqueous carbonaceous solid slurry, comprising a water-soluble copolymer having an average molecular weight of 1,000 to 500,000 and obtained by polymerizing the following monomer components (A), (B), (C) and optionally (D) and optionally a water-soluble copolymer obtained by neutralizing said copolymer with a base, the monomers being selected from the groups . ~

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(A) 0.1 to 7 mol% of a polyalkylene glycol mono(meth) acrylate type monomer represented by the general formula I:

CH2= C-Coo-(R2o)nR3 (I) wherein Rl stan~s for hydrogen atom or methyl group, R2 for alkylene group having 2 to 4 carbon atoms, n for a numeral in th~ range of 1 to loo on the average, and R3 ~or an alkyl, alkenyl, aryl, aralkyl, cyclic alkyl or cyclic alkenyl group having 1 to 30 carbon atoms, or a monovalent organic group having 4 to 30 carbon atoms derived from a heterocyclic compound, (B) 5 to 94.9 mol% of a sulfoalkyl (meth~acrylate type ; 20 monomer represented by the general formula II:

CH2 = C-CooR5so3x (II) wherein R4 stands for hydrogen atom or methyl group, Rs for alkylene group having 1 to 4 carbon atoms and X for hydrog~n atom, an alkali metal atom, an alkaline earth m~al atom, an ammonium group, or an amine base; and (C) 5 to 94.g mol% of an unsaturated carboxylic acid type ~onomer represented by the general formula III:

C = C-COOY
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. R7 (III) , ~,.~
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13281~3 wherein R6 and R7 independently stand for a hydrogen atom, methyl group, or -COOY, providing that R6 and X7 do not simultaneously stand for -COOY, R8 stands for hydrogen atom, methyl group, -COOY, or -CH2COOY providing that R6 and R7 independently stand for hydrogen atom or methyl group where R8 stands for -COOY or -CH2COOY, and Y stands for a hydrogen atom, alkali metal atom, alkaline earth metal atom, group, or amine base, atom, alkali metal atom, alkaline earth metal atom, ammonium group, or amine base, providing that the total amount of the monomer components (A), (B) and (C), is 100 mol% .
BRIEF DESCRIPTION OF THE DRAWING
Fig. 1 is a schematic cross section of an apparatus for determining the degree of solid sedimentation in an aqueous coal slurry.
DETAILED DESCRIPTION OF THE INVENTION
As examples of the carbonaceous solid to be used in the aqueous carbonaceous solid slurry composition contemplated by the present invention, coal, cokes such as coal coke, oil coke and the like, and ~itches such as - petroleum pitch, coaltar pitch and the like can be cited.
Among other carbonac~ous solids mentioned above, coal proves particularly effective. This coal may be any of the various ~inds of coal such as, for example, anthracite (rock coal) bituminous coal, sub-bituminous coal, and lignite. This invention does not discriminate the coal by the kind or the origin or by the water content or the chemical composition. The coal is used as the standard in a form pulverized by the conventional wet or dry method into fine particles, of which not less than 50% by weight, preferably 70 to 90% by weight, will pass a 200-mesh sieve. The fine coal powder concentration in ` the slurry composition is in the range of 40 to 90% by weight, preferably 50 to 90% by weight. If the concentration is less than 40% by weight, the aqueous slurry composition is not practical from the viewpoints lBl ~

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1 32~ 1 43 of economy, efficiency of transportation, and efficiency of combustion.
The water-soluble copolymer which is effective as a dispersant for the aqueous carbonaceous solid slurry contemplated by the present invention is a water-soluble ,fr ~ 5a ~B
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. ~ . -, copolymer having an average molecular weight o~ 1,000 to 500,000 and produced by copolymerizing the aforementioned monomers (A), (B), (C), and (D) in proportions such that the amount of the monomer (A) falls in the range of 0.1 to 7 mol~, that of the monomer (B) in the range o~ 5 to 94.9 mol%, that of the monomer (C) in the range of 5 to 94.9 mol%, and that of the monomer (D) in the range of 0 to 20 mol% (providing that the total amount of the monomers (A), (B), (C), and (D) is 100 mol~) and /or a water-soluble copolymer obtained by neutralizing the copolymer with a basic substance.
The monomer (A~ is represented by the afore-mentioned general formula I and can be obtained by the known method. Examples of the monomer (A) include alkoxy-polyalkylene glycol (meth)acrylates alkoxylated with alkyl groups having up to 30 carbon atoms such as methoxy-polyethylene glycol (meth)acrylate, methoxypolypropylene glycol (meth)acrylate, methoxypolybutylene glycol (meth)-acrylate, ethoxypolyethylene glycol (meth)acrylate, ethoxy-polypropylene glycol (meth)acrylate, ethoxypolybutylene glycol (meth)acrylate, and methoxypolyethylene glycol-polypropylene glycol (meth)acrylate; alkenoxypolyalkylene glycol (meth)acrylates alkenoxylated with alkenyl groups having up to 30 carbon atoms; aryloxypolyalkylene glycol (meth)acrylates such as phenoxypolyethylene glycol (meth)-acrylate, nonylphenoxypolyethylene glycol (meth)acrylate, naphthoxypolyethylene glycol (meth)acrylate, phenoxy-polypropylene glycol (meth)acrylate, naphthoxypo]yethylene glycolpolypropylene glycol (meth)acrylate, and p-methyl-phenoxypolyethylene glycol (meth)acrylate; aralkyloxy-polyalkylene glycol (meth)acrylates such as benzyloxy-polyethylene glycol (meth)acrylate; cyclic alkoxy-polyalkylene glycol (meth)acrylates such as cyclohexoxy-polyethylene glycol (meth)acrylate; cyclic alkenoxy-polyalkylene glycol (meth)acrylates such as cyclopentenoxy-polyethylene glycol (meth)acrylate; and heterocyclic ethers :

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1 ~28 1 43 of pslyalkylene glycol mono(meth)acrylate such a~
pyridyloxypolyethylene glycol (meth) acrylate and thienyloxypolyethylene glycol (meth)acrylate. One member or a mixture o~ two or more members selected from the group of the monomers enumerated above can be used. In all the monomers of (A) usable in the present invention, the monomers which readily yield to the aforementioned copolymerization and are available inexpensively and, therefore, prove particularly desirable are those which meet the general formula I on the condition that Rl stands for hydrogen atom or methyl group, R2 for ethylene group or propylene group, n for a numeral in the range of 2 to 50 on the average, and R3 for alkyl groups having 1 to 20 carbon atoms, phenyl, or naphthyl group, or alkylphenyl group possessing 1 to 3 alkyl groups each o~ 1 to 10 carbon atoms a~ a sub~tituent, or benzyl group.
Specifically R3 may be selected from the group consisting of a methyl group, ethyl group, propyl group, isopropyl group, octyl group, phenyl group, naphthyl group, methylphenyl group, dimethylphenyl group, nonylphenyl group, dinonylphenyl group, octylphenyl group, dioctylphenyl group, or benzyl group. Typical examples of the monomers (A) just described include alkoxypolyethylene glycol (meth)acrylates and alkoxypolypropylene glycol (meth)acrylates alkoxylated ' with alkyl groups having up to 20 carbon atoms such as methoxypolyethylene glycol (meth~acrylate, methoxypolypropylene glycol (meth)acrylate, ethoxypolyethylene glycol (meth~acrylate, ethoxy-polypropylene glycol (meth)acrylate, octyloxypolyethylene qlycol (meth)acrylate, and methoxypolyethylene glycol-polypropylene glycol (meth)acrylate, phenoxypolyethylene glycol (meth3acrylate, p-methylphenoxypolyethylene glycol (meth)acrylate, nonylphenoxypolyethylene glycol (meth)-acrylate, octylphenoxypolyethylene glycol (meth~acrylate, :, 4~
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1328~3 naphthoxypolyethylene glycol (meth)acrylate, phenoxy-polypropylene glycol 5meth)acrylate, p-methylphenoxy-polypropylene glycol (meth) acrylate, naphthoxypolyethylene glycol-polypropylene glycol (meth)acrylate, benzyloxypolyethylene glycol (meth)acrylate, and benzyloxypolypropylene glycol (meth)acrylate. One member or a mixture of two or more members selected f rom the group of monomers enumerated above can be used.
The monomer (B) is represented by the general .~ .

7a iB

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formula II and can be produced by the known method.
Examples of the monomer (B) include 2-sulfoethyl (meth)-acrylate, 3-sulfopropyl (meth)acrylate, 2-sulfopropyl ~meth)acrylate, 1-sulfopropan-2-yl (meth)acrylate, and 4-sulfobutyl (meth)acrylate; sodium, potassium, and other alkali metal salts and magnesium, calcium, and other alkaline earth metal salts of such (meth)acrylates; and ammonium salts and organic amine salts thereof. One member or a mixture of two or more members selected from the group of monomers cited above can be used. Examples of the amine for the formation of the amine salts mentioned above include alkyl amines such as methyl amine, dimethyl amine, trimethyl amine, ethyl amine, diethyl amine, triethyl amine, n-propyl amines, isopropyl amines, and butyl amines; alkanol amines such as ethanol amine, diethanol amine, triethanol amine, isopropanol amine, and diisopropanol amine; and pyridine.
In the monomers of (B) enumerated above, the monomers which are available easily and capable of produciny the copolymer of particularly desirable properties are those which satisfy the general formula II on the condition that R4 stands for hydrogen atom or methyl group, R5 for ethylene group or propylene group, and X for hydrogen atom, sodium atom, potassium atom, ammonium group, or alkanol amine base.
Preferably, the alkanol amine base is monoethanol amine base, diethanol amine base, or triethanol amine base.
The monomer (C) is represented hy the general formula III and can be obtained similarly by the known method. Examples of the monomer (C) include acrylic acid, ; methacrylic acid, crotonic acid, itaconic acid, maleic acid, fumaric acid, and citraconic acid; and alkali metal salts, alkaline earth metal salts, ammonium salts, and organic amine salts of the acids mentioned above. one member or a mixture of two or more members selected from the group of monomers cited above can be used. Examples of the amine for the formation of the amine salts mentioned above are similar to those mentioned previously with respect to the monomers ~.

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-~ 1 328 1 43 of the general formula II. In the monomers of tC) enumerated above, the monomers which are available inexpensively and capable of imparting satisfactory dispersibility to the produced copolymer are maleic acid and (meth) acrylic acid; and sodium salts, potassium salts, ammonium salts, monoethanol amine salts, diethanol amine salts, triethanol amine salts, and other similar alkanol amine salts of the acids mentioned above.
The monomer (D) has only to be copolymerizable with the monomers (A), (B), and (C) and can be used in a proportion incapable of impairing the effect of this invention. Examples of the monomer (D) include alkyl (meth)acrylates such as methyl (meth)acrylate, ethyl (meth)-acrylate, isopropyl (meth)acrylate, butyl (meth)acrylate, and lauryl (meth)acrylate; cyclohexyl (meth)acrylate;
various sulfonic acids such as vinyl sulfonic acid, styrene sulfonic acid, alkyl sulfonic acid, methallyl sulfonlc acid, and 2-acrylamide-2-methylpropane sulfonic acid, i.e. other than the sulfonic acids falling under the category of the monomer (B); alkali metal salts, alkaline earth metal salts, ammonium salts, and organic amine salts of the acids mentioned above; hydroxyl group-containing monomers such as hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, and polyethylene glycol mono(meth)acrylate; various (meth)~
acrylamides such as (meth)acrylamide and N-methylol (meth)-acrylamide; aromatic vinyl compounds such as styrene and p-methylstyrene; and vinyl acetate, propenyl acetate, and vinyl chloride. One member or a mixture of two or more members selected from the group of monomers mentioned above can be used.
In the preparation of the water-soluble copolymer by the copolymerization of these monomers (A), (B), tC), and optionally (D), the monomers are used in proportions such that the amount of the monomer (A) falls in the range of 0.1 to 7 mol%, preferably 0.2 to 5 mol%, that of the monomer (B) in the range of 5 to 94~9 mol%, preferably 10 to 89.8 mol%, : _g _ .

1 328 1 ~3 that of the monomer ~C) in the range of 5 to 94.9 mol%, preferably 10 to 89.8 mol%, and that of the monomer (D) in the range of 0 to 20 mol~, preferably 0 to 10 mol%
(providing that the total amount of the monomers (A), (B), (C), and (D) is 100 mol%). If the monomers are used in amounts deviating from the respective ranges specified above, the produced water-soluble copolymer exhibits an insufficient quality for use as a dispersant for the aqueous carbonaceous solid slurry. Particularly when the monomer (A) is used in an amount either below 0.1 mol% or above 7 mol%, the produced copolymer exhibits no sufficient dispersing property to the coal without reference to the kind thereof. When the monomer (B) is used in an amount below 5 mol%, the produced copolymer exhibits a notably lowered dispersing property to the coal of a high ash content containing polyvalent metals in a large amount.
When the monomer (C) is used in an amount below 5 mol%, the produced copolymer exhibits a notably low dispersing property to the coal having a low ash content of not more than 3% by weight (on the anhydrous basis) or the coal of a high degree of carbonization. It is only when the monomers (A), (B), (C), and optionally (D) are used within the respective ranges specified above that the produced water-soluble copolymer is capable of manifesting the outstanding dispersing property on the carbonaceous solid without reference to the kind and the quality thereof, such as, for example, the ash content, the water content, and the chemical composition thereof.
`For the production of a water-soluble copolymer which is useful as the dispersant for the aqueous carbonaceous solid slurry of the present invention, it suffices to copolymerize the monomer components in the `presence of a polymerization initiator. The copolymeriza-tion can be carried out by polymerization in a solvent, bulk polymerization, or some other similar method.
The polymerization in a solvent can be performed .
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batchwise or continuously. Examples of the solvent usable in this polymerization include water; lower alcohols such as methyl alcohol, ethyl alcohol, and isopropyl alcohol;
aromatic, aliphatic, and heterocyclically aliphatic hydrocarbons such as benzene, toluene, xylene, cyclohexane, n-hexane, and dioxane; ethyl acetate; and ketones such as acetone, and methylethyl ketone. In consideration of the solubility of the monomers used as raw materials and the copolymer as a product and -the convenience of use of the copolymer it is desirable to use at least one member selected from the group consisting of water and lower alcohols having 1 to 4 carbon atoms. In the lower alcohols of 1 to 4 carbon atoms, methyl alcohol, ethyl alcohol, and isopropyl alcohol are particularly effective selections.
When the polymerization is carried out in water as the medium, the polymerization initiator to be used therein may be any of the initiators of conventional use. For example, a water-soluble polymerization initiator such as ammonium or alkali metal persulfate or hydrogen peroxide can be used. In this case, an accelerating agent such as sodium hydrogen sulfite may be used in combination with the polymerization initiator. For the polymerization using a lower alcohol, an aromatic hydrocarbon, an aliphatic hydrocarbon, ethyl acetate, or a ketone compound as the solvent, any of the initiators of conventional use can be used. Examples of the polymerization initiator usable therein include peroxides such as benzoyl peroxide and lauroyl peroxide; hydroperoxide such as cumene hydro-peroxide; and aliphatic azo compounds such as azo-bis-isobutyronitrile. The amount of the polymerization initiator to be used is in the range of 0.1 to 10 ~ by weight, preferably 0.2 to 5 % by weight, based on the total amount of the monomers being used in the polymerization. In this case, an accelerating agent such as an amine compound may be used in combination with the polymerization initlator. When a mixed solvent consisting of water and a .~ . ' . - , -. . . .

~ 328 1 43 lower alcohol is used, a polymerization initiator or a combinatioin of a polymerization initiator with an accelerating agent may be suitable selected from the various polymerization initiators and accelerating agents mentioned above and put to use therein. The polymerization temperature is suitably fixed, depending on the particular kinds of solvent and polymerization initiator to be used.
Generally the polymerization is carried out at a temperature in the range of 0 to 120C, preferably 20 to 100C.
The bulk polymerization requires use of a polymerization initiator which may be a peroxide such as benzoyl peroxide or lauroyl peroxide, a hydroperoxide such as cumene hydroperoxide, or an aliphatic azo compound such as azo-bis-isobutyronitrile. It is carried out at a temperature in the range of 50 to 150C. The amount of the polymerization initiator to be used therein is in the range of 0.1 to 10 % by weight, based on the total amount of the monomers being used in the polymerization.
Desirably, the water-soluble copolymer has a molecular weight in the range of 1,000 to 500,000, preferably 5,000 to 300,000.
The water-soluble copolymer which is obtained by the copolymerization performed as described above can be used in its unmodified form as the dispersant of this invention for the aqueous carbonaceous solid slurry.
Optionally, it may be neutralized with a basic substance before it is put to use as the dispersant. As examples of the basic substance usable for the neutralization, hydroxides, oxides, and carbonates of alkali metals and alkaline earth metals, ammonia, and organic amines can be cited. Examples of the organic amines include alkyl amines such as methyl amine, dimethyl amine, trimethyl amine, ethyl amine, diethyl amine, triethyl amine, n-propyl amines, isopropyl amines, and butyl amines; alkanol amines such as monoethanol amine, diethanol amine, triethanol amine, isopropanol amine, and diisopropanol amine; and pyridine.

, . .

1 328 1 ~3 The dispersant of t.his invention for an aqueous carbonaceous solid slurry serves to combine a carbonaceous solid with water and give rise to an aqueous carbonaceous solid slurry composition contemplated by this invention.
The amount of the dispersant to be added in this case is not specifically limited. The dispersant can be used effectively in an amount to be selected in a wide range.
From the economic point of view, however, it is used generally in an amount in the range of 0.01 to 5 parts by weight, desirably 0.05 to 2 parts by weight, and more desirably 0.1 to l part by weight, based on lOO parts by weight of the carbonaceous solid (on dry basis).
The carbonaceous soiid content in the aqueous carbonaceous soid slurry composition of this invention is not specifically limited. With consideration to the efficiency of transportation and the efficiency of combustion of the composition, this content is generally desired to fall in the range of 40 to 90% by weight, preferably in the range of 50 to 90% by weight, and more preferably in the range of 55 to 85% by weight.
The production of the aqueous carbonaceous Solid slurry composition by the use of the dispersant of this invention for an aqueous carbonaceous solid slurry may be accomplished by kneading a preparatorily pulverized carbonaceous solid and water with the dispersant, or by wet-pulverizing a carbonaceous solid with water and the dispersant or solution. The dispersant may be used prescribed amount or may be used devidedly, during pulverization or kneading.
The apparatus to be used for the conversion of the mixture into a slurry may be any of the devices conventionally available for converting a carbonaceous solid into a slurry with water.
The present invention does not discriminate the aqueous carbonaceous solid slurry composition thereof by the manner of incorporation of the dispersant or by the manner :.

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of conversion of the mixture into a slurry.
The aqueous carbonaceous solid slurry composition of the present invention, when necessary, may incorporate therein a polymer, a surfactant, or a fine inorganic powder as a dispersion aid or stabilizer besides the aforementioned water-soluble copolymer. When the dispersant of this invention is used in combination with a suitably selected dispersion aid or stabilizer, the aqueous carbonaceous solid slurry composition aimed at can be obtained in a higher concentration with high flowability and high stability against sedimentation of solid during a long period.
Examples of the dispersion aid to be used in combination with the dispersant of the present invention for producing an aqueous carbonaceous solid slurry composition having high flowability and excelling in stability include polystyrene sulfonic acid or salts thereof, styrene-styrene sulfonic acid copolymer or salts thereof, aliphatic aldehyde addition condensates of sulfonated naphtalene, alkyl naphtalene, or creosote oil and salts thereof, or aliphatic aldehyde addition condensates of sulfonate group-containing amino triazines and salts thereof, compounds containing a tricyclodecane or tricyclodecene skeleton and a sulfonate group as essential components in the molecular unit thereof, and polyether compounds obtained by adding alkylene oxides to formalin condensates of alkylphenols, and one or more than one kinds of these compounds can be U5 ed.
The polystyrene sulfonic acid or salts thereof or the styrene-styrene sulfonic acid copolymer or salts thereof is obtained by polymerizing a monomeric styrene sulfonic acid or by copolymerizing styrene with styrene sulfonic acid, or then by neutralizing the polymer or the copolymer obtained with basdic substances. Otherwise, the polymer or copolymer may be obtained by sulfonating polystyrene by the conventional method. Desirably, the salt of sulfonic acid is an alkali metal or ammonium salt. It may contain a partially residual hydrogen. It may otherwise be an "` 1 328 1 ~3 alkaline earth metal salt or an amine salt. The molecular weight of this polymer is desired to exceed 1,000, preferably to fall in the range of 2,000 to 50,000.
The aliphatic aldehyde addition condensates of sulfonated naphthalene, alkyl naphtalene or creosote oil, or the salt thereof is obtained by subjecting a sulfonation product to addition condensation with an aliphatic aldehyde or by effecting this addition condensation and subsequently sulfonating the addition condensate. Among other products of the addition condensation, those obtained by formalin condensation prove to be particularly effective. ~he degree of condensation is the desired to fall in the range of 1.2 to 60, preferably 1.2 to 50. If the degree of condensation is less than 1.2, dispersing property is not sufficient.
Conversely, if this degree exceeds 60, the produced condensate proves to be impracticable becasue of excessive polymerization and insufficient solubility. Examples of the salt of sulfonate include salts of alkali metals such as sodium and potassium, salts of alkaline earth metals such as calcium and magnesium~ ammomium salts, and amine salts. The term "creosote oil" refers to the neutral oil of a boiling point of not lower than 200C contained in the tar from coal carbonization or to an alkylation product of the neutral oil. Heretofore, the creosote oil has been defined in various ways. According to Japanese Industrial Standard (JIS) K 2439 (1978), it is a product obtained by separating crystalline components such as naphthalene and anthracene from a mixture of distillates of grades of not lower than , middel oil, i.e. such distillates as middle oil, heavy oil, and anthracene oil, resulting from distillation of coal tar, further separating and recovering phenols and pyridines, and suitably combining the remaining distillates in a fixed formula. The product is classified into three kinds, No. 1, No. 2, and No. 3. Creosote oil, No. 1, for example, is a mixture of a plurality of compounds which has a specific gravity of not less than 1.03 and a water content of not ~ ' - . .- ' ~

1 32~1 43 more than 3% and which has a fraction of not more than 25%
boiling at tempratures not exceeding 235C, a fraction of not less than 40~ boiling at temperatures between 235 and 315C, and a fraction of not less than 50~ distilling out at temeratures not exceeding 315C.
The creosote oil defined by JIS K 2439 (1978) mentioned above can be used in its unmodified form of a mixture of a plurality of component compounds. Distillates obtained by distilling the creosote oil such as, for example, the fractions boiling at 200C to 250C, 240C to 260C, 250C to 270C, and 270C to 300C are all usable.
The creosote oil and distillates may be alkylated before they are put to use. The method to be used for effecting this alkylation is not specifically defined. For example, a method which effects sulfonation and alkylation simultaneously by allowing the sulfonation by the use of fuming sulfuric acid or concentrated sulfuric acid to proceed in the presence of a corresponding alcohol may be used.
' The condensation product OL a sulfonate group-containing amino-triazine with an aliphatic aldehyde or the salt thereof is an amino-triazine condensate or the salt thereof. Examples of the salt of sulfonate group include alkali metal salts, alkaline earth metal salts, ammonium salts, and amine salts. One example of the condensation product is a condensate produced by the procedure described in Japanese Patent Publication SHO 43(1968)-21,659. This condensate is generally produced by condensing an amino-s-triazine such as, for example, melamine, ` hexamethylol melamine, acetoguanamine, or benzoguanamine in the presence of an aliphatic aldehyde, preferably i formaldehyde and subsequently sulfonating the resulting condensation product with a sulfonating agent such as, for example, sulfurous acid, sulfuric acid, sulfonic acid, hydrogen sulfite, or a salt thereof, disulfite, dithionite, or pyrosulfite or by condensing an amino-s-triazine sulfonic , ~ ~
-acid with an aldehyde, preferably formaldehyde. The sulfonated melamine resin is one of the preferred a sulfonate group-containing condensation product.
The compound containing a tricyclodecane tricyclodecene skeleton and a sulfonate group as essential components in the molecular unit thereof is at least one of the following compounds tl) through (6). The tricyclodecane skeleton and tricyclodecene skeleton have the following structures (IV) and (V) (namely, they are tricyclo 5,2,1,02'6 -decane and decene).

~ (IV) f~ (v ) (1) The sulfonate obtained by polymerizing a cyclopentadiene or a cyclopentadiene derivative represented by the general formula (a) or general formula (b) as shown in Japanese Patent Application SHO
57(1982)35,148 and sulfonating the resultant polymer.

Rll~
(a) wherein Rll stands for hydrogen atom or alkyl group having 1 to 3 carbon atoms, : . . : : , .
. . -Rl ~ (b) wherein R12 and R13 indepenedently stand for hydrogen atom or alkyl group having 1 to 3 carbon atoms.
The sulfonate obtained by causing a cyclopentadiene or a cyclopentadiene derivative represented by the general formula (a) or general fo.rmula (b) as shown in Japanese Patent Application SHO 57(1982)-35,149 to react with a compound represented by the general formula (c) and sulfonating the resulting reaction mixture or the condensate of the sulfonateO

(c) Rl 5 wherein R14 and R15 independently stand for hydrogen atom or alkyl group having 1 to 6 carbon atoms.

(3) The condensate obtained by condensing a cyclopentadiene derivative sulfonate represented by the general formula (d) as shown in Japanese Patent Application S~O
! 57(1982)-35,147. .

~ P
wherein R16, R17, and R18 independently stand for a hydrogen atom or an alkyl group having 1 to 6 carbon ; atoms, Rl9 and R20 independently stand for a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, ~, ;:~ . . ~
:

stands for 1 or 2, and M stands for hydrogen, alkali metals, alkaline earth metals, ammonium group, or amine base.
~4) The polymer or copolymer of a sulfonate of dicyclopentadiene represented by the general fonnula (e) shown in Japanese Patent Application SHO
57~19~2) 175,666.

= ~50 ~M (e) wherein p and M have the same meanings as defined in the formula ~d) above.
(5) The polymer or the copolymer of a sulfonate of hydroxydicyclopentadiene represented by the general formula (f) as shown in Japanese Patent Application SHO
58(1973)-43,729.

~ ~50~

wherein p and M have the same meanings as defiend in the formula (d) above.
(6) The condensate obtained by condensing a disulfonate of dicyclopentadiene derivative represented by the general formula (g) as shown in Japanese Patent Application SHO
~: 58(1973)-~2,205.

~ ~)p wherein R 21 and R22 independently stand for a hydrogen :
.
.

. . - . . . . . . .
:. , : : . ~ . -: . . : - .

atom or an alkyl group having 1 or 2 carbon atoms and M
and p have the same meanings as defined in the formula (d) above.
Concrete co~lpounds which can be represented by the general formula ~a) or general formula (b) in the paragraph (1) above include alkylcyclopentadienes such as methylcyclopentadiene, ethylcyclopentadiene, and propyl-cyclopentadiene besides cyclopentadiene and dimers of any of combinations of such monomers such as, for example, dicyclopentadiene. Among other concrete compounds cited above, cyclopentadiene and dicyclopentadiene and the mixture of the two compounds prove particulary desirable. Concrete compounds which can be represented by the general formula (c) in the paragraph (2) above include benzene, toluene, xylenes (o-, m-, and p-), and benzene derivatives such as ethyl benzenel n-propyl benzene, isopropyl benzene, methylethyl benzenes (o-, m-, and p-), n-butyl benzene, sec-butyl benzene, tert-butyl benzene, ispropyl toluenes (o-, m-, and p-), amyl benzene, hexyl benzene, amyl toluenes (o-, m-, and p-), and other similar mono- and dialkyl-subsituted benzenes. Among other typical compounds cited above, benzene, toluene, xylene, propyl benzene, and :
~butyl ~enzene prove particularly desirable.
:~Among the polyether compounds obtained by adding `alkylene oxides to formalin condensates of alkylphenols, `~following compounds represented by the general formula (h) are preferable:
~ O~Rl~Otm~ ~
~~ ~ ~ CH2 (h) wherein R9 stands for an alkyl group of 5 to 12 carbon atoms, (RlOO)m for ethylene oxide or a block polymer of propylene oxide and ethylene oxide, m for a numeral in the range of 1 to 100 in the case of ethylene oxide alone or in `~

' ' , '::

~ ' ' ;

1 32~ 1 43 the range of 1 to 120 in the case of the block polymer of propylene oxide and ethylene oxide, the content of ethylene oxide is in the range of 30 to 95 mol%, and 1 for the degree of condensation in the range of 2 to 50.
The polyether compounds obtained by adding alkylene oxides to formalin condensates of alkylphenols is a formalin condensate of polyoxyalkylene alkylphenol having a molecular weight of 1,000 to 600,000, preferably 5,000 to 300,000, and obtained by using as a starting material a formalin condensate having an average condensation degree of 2 to 50, preferably 7 to 40, and resulting from formalin condensation of an alkyl phenol in the absence of a solvent, mixing the starting material with a hydrocarbon oil having a boiling point of not lower than 150C and serving as an oil for the improvement of the reactivity of alkylene oxide, and chemically adding an alkylene oxide to the resulting mixture.
Advantageously, the dispersion aid which can be used in combination with the dispersant of the present invention is used in an amount in the range of 0.01 to 5 parts by weight, preferably 0.02 to 2 parts by weight, based on 100 parts by weight of the carbonaceous solid.
Examples of the stabilizing agent which can be advantageously used in combination with the dispersant of the present invention include clayish minerals~ poly-saccharides, and alkali metal salts of polyacrylic acid.
One member or a mixture of two or more members selected from the group of stabilizing agents cited above can be used~
The clayish minerals, i.e. hydrated alumina-silicates, fall under various types such as the mont-morillonite family, the kaolin family, and the illite family. Among other claish minerals, those of the mont-morillonite family prove particularly desirable.
Typical examples of the polysaccharide include microorganic polysaccharides such as xanthane gum, glyco-saminoglycan, mannans, carboxymethyl cellulose, alkali metal .'' ~ -21-'~"
: , :

. :.: -::i . :: i salts thereof, and hydroxyethyl cellulose. Among other polysaccharides enumerated above, the sodium salt of carboxymethyl cellulose (CMC), hydroxyethyl cellulose (HEC) and xanthane gum prove particularly desirable. The CMC is obtained by using cellulose (pulp), monochloroacetic acid, and sodium hydroxide as main raw materials and acquires solubility in water by having a hydrophilic sodium carboxymethyl group (-CH2cOoNa~ incorporated in the cellulose. Specifically, it is produced by first causing sodium hydroxide to react upon cellulose thereby forming alkali cellulose, subsequently allowing monochloroacetic acid to react upon the alkali cellulose thereby inducing etherification of the hydroxyl group of the cellulose and consequent incorporation of a carboxymethyl group in the cellulose~ In this case, it is theoretically possible to produce CMC of the etherification degree of 3, i.e. to have all the three hydroxyl groups of each cellulose unit etherified completely. Most CMC products available in the market generally have degrees of etherification in the range of 0.5 to 1.5. The HEC is obtained by using cellulose ~pulp), ethylene oxide, and sodium hydroxide as main raw materials and acquires solubility in water by addition of a hydrophilic hydroxyethyl group ~-cH2cH2oH) to the cellulose.
Sepcifically, it is produced by first causing sodium hydroxide to react upon cellulose thereby forming alkali cellulose and subsequently allowing ethylene oxide to react upon the alkali cellulose, and giving rise to water-soluble hydroxyethyl cellulose.
In all the alkali metal salts of polyacrylic acid, polyacrylic acid sodium salt proves particularly desirable as a stabilizer.
The stabilizer of the foregoing description which can be used in combination with the dispersant of the present invention is used in an amount in the range of 0.0001 to 2 parts by weight, preferably 0.0005 to 1 part by weight, based on 100 parts by weight of the carbonaceous .

;, ~ .
.. . : . :

.. : , . ' , :, solid.
It is optional to use the dispersant of the present invetnion in combination with both the dispersion aid and the stabilizer mentioned above.
The aqueous carbonaceous solid slurry composition of this invention can contain therein a basic substance as a pH adjusting agent in addition to the dispersant used as an essential component, besides the dispersion aid and the stabilizer used as optional additives. For the aqueous carbonaceous solid slurry composition with high flowability, the pH of the composition is desired to be in the range of 4 to 11, preferably 6 to 10. This composition can be produced in a high concentration with high flowability by additional-ly using therein the pH adjusting agent in an amount suitably selected for the pH value of the composition to fall in the range mentioned above.
Desirably, the pH adjusting agent is used in an amount in the range of 0.01 to 5 parts by weight, preferably 0.05 to 0.5 part by weight, based on 100 parts by weight of the carbonaceous solid.
` Examples of the pH adjusting agent which can be optionally incorporated during the preparation of the aqueous carbonaceous solid slurry composition of the present invention include basic substances such as hydroxides, oxides, and carbonates of alkali metals; hydroxides, oxides, and carbonates of alkaline earth metals; ammonia, and organic amines. Among the pH adjusting agents cited above, sodium hydroxide~ potassium hydroxide, calcium hydroxide, magnesium hydroxide, ammonia, ethanol amine, diethanol amine, and triethanol amine are particularly desirable.
The aqueous carbonaceous solid slurry composition ` of the present invetnion, when necessary, can additionally incorporate therein a rust preventive, a corrosionproofing agent, an antioxidant, a defoaming agent, an antistatic agent, and a solubilizing agent.
~., ' : . :.- ~

Now, the aqueous carbonaceous solid slurry composition of the present invention will be described more specifically with reference to comparative experiments and working examples. It should be noted, however, that this invention is not limited to these working examples.
Wherever "parts" is mentioned hereina~ter, the term will mean "parts by weight" unless otherwise specified.
Referential Example 1 In a polymerization vessel fitted with a thermometer, a stirrer, two dropping funnels, and a gas inlet tube, 100 parts of water placed therein were stirred and the inner gas of the polymerization vesel was displaced with nitrogen. Then, in the atmosphere of nitrogen the water was heated to 95C. Subsequently, to the hot water kept at this temperature, a monomer mixture solution containing 2.1 parts of methoxypolyethylene glycol methacrylate (containing an average of 15 ethylene oxide units per molecule and having an average molecular weight of 760) as monomer (A), 80.2 parts of sodium salt of 2-sulfoethyl methacrylate (having a molecualr weight of 216) as monomer (B), 17.7 parts of sodium methacrylate (having a molecular weight of 108) as monomer (C), and 150 parts of water was added dropwise through one of the dropping funnels over a period of 120 minutes. At the same time, an aqueous solution containing 0.8 part of ammonium persulfate and 50 parts of water was added dropwise through the other dropping funnel to the same hot water over a period of 140 minutes.
After the dropwise addition was completed, polymerization already initiated was continued at the same temperature for minutes and then cooled. Consequently, there was obtained a copolymer (1) having an average molecular weight o~ 60,000.
Referential Example 2 A copolymer (2) having an average molecular weight of 40,000 was obtained by following the procedure of Referential Example 1, excepting 2.7 parts of methoxy .: .

?~ `

~`' ' .
:'~' .. .

.
~. ' .

polyethylene glycol methacrylate (containing an average of 6 ethylene oxide units per molecule and having an average molecular weight of 364) was used as monomer (A), 57.4 parts of ammonium sal-t of 2-sulfoethyl acrylate ~having a molecular weight of 197) was used as monomer (B), 39.9 parts of ammonium acrylate (having a molecular weight of 89) was used as monomer (C), and the amount of ammonium persulfate was changed to 1.5 parts.
Referential Example 3 A copolymer (3) was obtained by preparing a copolymer having an average molecular weight of 200,000 following the procedure of Referential Example 1, excepting 1.9 parts of ethoxypolyethylene glycol acrylate (containing an average of 15 ethylene oxide units per molecule and having an average molecular weight of 760) was used as monomer (A), 91.9 parts of sodium salt of 2-sulfoethyl methacrylate (having a molecular weight of 216) was used as monomer (B), 6.2 parts of methacrylic acid ~having a molecular weight of 86) was used as monomer (C), and the amount of ammonium persulfate was changed to 0.4 part, and subsequently neutralizing the copolymer with 4.4 parts of monoethanol amine.
Referential Example 4 A copolymer (4) was obtained by preparing a copolymer having an average molecular weight of 60,000 following the procedure of Referential Example 1, excepting 6.4 parts of n-propoxypolyethylene glycol-polypropylene glycol acrylate (having an average of 20 ethylene oxide units and an average of 5 propylene oxide units per molecule and having an average molecular weight of 1,284) was used as monomer (A~, 71.7 parts of potassium salt of 2-sulfopropyl acrylate (having a molecular weight of 232) was used as monomer (B), 21.0 parts of acrylic acid (having a molecular weight of 72) was used as monomer (C), and 0.9 part of acryl amide (having a molecular weight of 71) was additionally used as monomer (D), and the amont of ammonium persulfate .

~ .
,:, ; . .. :.
.:: . . .. ~:
: :-~: :

~ 328 1 43 was changed to 1 part, and subsequently neutralizing thecopolymer with 16.4 parts of potassium hydroxide.
Referential Example 5 A copolymer (5) having an average molecular weight of 150,000 was obtained by following the procedure of Referential Example 1, excepting 2.0 parts of octyloxypolyethylene glycol acrylate (containing an average of 30 ethylene oxide units per molecule and having an ~ average molecular weight of 1,504) was used as monomer (A), :. 54.4. parts of sodium salt of 2-sulfoethyl acrylate (having a molecular weight of 202) was used as monomer (B), 30.6 parts of sodium acrylate (having a molecular weight of 94) ~ and 13.0 parts of disodium fumarate (having a molecular .. weight of 160) were used as monomer (C), and the amount of ammonium persulfate was changed to 0.5 part.
Referential Example 6 A copolymer (6) was obtained by preparing a copolymer having an average molecular weight of 30,000 following the procedure of Referential Example 1, excepting 6.5 parts of phenoxypolyethylene glycol methacrylate (containing an average of 15 ethylene oxide units per molecule and having an average molecular weight of 822) was used as monomer (A), 40.1 parts of monoethanol amine salt of 2-sulfoethyl methacrylate (having a molecular weight of 255) was used as monomer (B), 53.4 parts of methacrylic acid (having an average molecualr weight of 86) was used as monomer (C), and the amount of ammonium persulfate was changed to 2.0 parts, and subsequently neutralizing the .~ copolymer with 42.2 parts of an aqueous 25~ ammonia solution.
:~ Referential Example 7 A copolymer (7) having an average molecular weight : of 70,000 was obtained by following the procedure of - Referential Example 1, excepting 10.3 parts of naphthoxy-~: polyethylene glycol acrylate (containing an average of 40 ethylene oxide units per molecule and having an average , . , .
- .
, ~". . ' ~ ~, ;' . ; ~

~ 3~ 43 molecular weight of 1,958) was used as monomer (A)~ 22.4 parts of ammonium salt of 2-sulfoethyl methacrylate (having a molecular weight of 211) was used as monomer (B), 67.3 parts of potassium methacrylate (having a molecular weight of 124) was used as monomer(C), and the amount of ammonium persulfate was changed to 1.0 part.
Referential Example 8 A copolymer (8) having an average molecular weight o~ 20,000 was obtained by following the procedure of Referential Example 1, excepting 9.2 parts of p-methyl-: phenoxypolyethylene glycol methacrylate (containing an average of 10 ethylene oxide units per molecule and having an average molecular weight of 616) was used as monomer (A), 15.5 parts of sodium salt of 2-sulfoethyl methacrylate ~having a molecular weight of 216) was used as monomer (B), 75.3 parts of monoethanol amine salt of methacrylic acid (having a molecular weight of 147) was used as monomer (C), and the amount of ammonium persulfate was changed to 2.5 parts.
Referential Example 9 A copolymer (g) was obtained by preparing a copolymer having an average molecular weight of 60,000 following the procedure of Referential Example 1, excepting 4.7 parts of dimethylphenoxypolyethylene glycol acrylate ; (containing an average of 20 ethylene oxide units per molecule and having an average molecular weight of 1,056) was used as monomer (A), 61.8 parts of potassium salt of 2-sulfopropyl acrylate (having a molecular weight of 232) was used as monomer (B), 33.5 parts of arrylic acid (having a molecular weight of 72) was used as monomer (C), and the : amount of ammonium persulfate was changed to 1.0 part, and subsequently neutralizing the copolymer with 26.1 parts of potassium hydroxide.
Referential Example 10 ~! In a polymerization vessel fitted with a thermometer, a , stirrer, three dropping funnels, a gas inlet ":' ~ ~ 27 tube, and a reflux condenser, 90 parts of water placed therein was stirred and the inner gas of the polymerization vessel was displaced with nitrogen. Then, in an atmosphere of nitrogen the water was heated to 40C. Subsequently, to the hot water kept at this temprature, a monomer mixture solution containing 6.7 parts of nonylphenoxypolyethylene glycol acrylate (containing an average of 30 ethylene oxide units per molecule and having an average molecular weight of 1,595) as monomer (A), 61.5 parts of diethanol amine salt of 2-sulfoethyl methacrylate (having a molecular weight of 299) as monomer (B), 21.7 parts of methacrylic acid (having a molecular weight of 86) and 10.1 parts of disodium maleate (having a molecular weight of 160) as monomer (C), and 150 parts of water was added dropwise through one of the dropping funnels over a period of 120 minutes. At the same time, an aqueous solution containing 0.6 part of ammonium persulfate and 30 parts of water was added dropwise through one of the remaining three dropping funnels over a period of 140 minutes and an aqueous solution containing 0.3 part of sodium hydrogen sulfite and 30 parts of water was added dropwise through the remaining dropping funnel over a period of 140 minutes. After the dropwise addition was completed, polymeriztion already initiated was continued at the same temperature for 60 minutes and then cooled. Consequently, a copolymer having an average molecular weight of 100,000 was obtained. This copolymer was neutralized with 10.1 parts of sodium hydroxide, to afford a copolymer (10).
Referential Example 11 A copolymer (11) having an average molecular weight of 70,000 was obtained by following the procedure of Referential Example 10, excepting 10.1 parts of octyl-phenoxypolyethylene glycol-polypropylene glycol acrylate (containing an average of 25 ethylene oxide units and an average of 2 propylene oxide units per molecule and having an average molecular weight of 1,476) was used as monomer (~), 79.5 parts of sodium salt of 2-sulfoethyl acrylate (having a molecular weight of 202) was used as monomer (~), , :
: , .
.:.

1 32~ 1 43 10.4 parts of diethanol amine salt of methacrylic acid~having a molecular weight of 191) was used as monomer (C), and the amount of ammonium persulfate was changed to 0.8 part and that of sodium hydrogen to 0.4 part.
Xeferential Example 12 A copolymer (12) was obtained by preparing a copolymer having an average molecular weight of 60,000 following the procedure of Referential Example 10, excepting 8.8 parts of dinonylphenoxypolyethylene glycol methacrylate (containing an average of 30 ethylene oxide units per molecule and having an average molecular weight of 1,734) was used as m~nomer (A), 24.6 parts of 2-sul~oethyl methacrylate (having a molecular weight of 194) was used as monomer (B), 58.2 parts of disodium itaconate (having a molecular weight of 174) was used as monomer (C), ~.4 parts of sodium styrenesulfonate (having a molecular weight of 206) was additionally used as monomer (D), and the amount of ammonium persulfate was changed to 1.0 part and that of sodium hydrogen sulfite to 0.5 part, and subsequently neutralizing the copolymer with 5.1 parts of sodium hydroxide.
Referential Example 13 A copolymer (13) having an average molecular weight of 150,000 was obtained by following the procedure of Referential Example 10, exceptiny 5.8 parts of dioctyl-phenoxypolyethylene glycol acrylate (containing an average of 45 ethyler~e oxide units per molecule and having an average molecular weight of 2,352) was used as monomer (A), 83.3 parts of sodium salt of 2-sulfoethyl methacrylate (having a molecular weight of 216) was used as monomer (B), 10.9 parts of ammonium methacrylate (having a molecular weight of 103) was used as monomer (C), and the amount of ammonium persulfate was changed to 0.5 part and that of sodium, hydrogen ~ulfite to 0.23 part.
Referential Example 14 A copolymer (14) having an average molecular ' ~
~ 29 ,.
, : ' ~ .

weight of 20,000 was ~btained by ~ollowing the procedure of Referential Example 10, excepting 7.8 parts of benzyl-oxypolyethylene glycol acrylate (containing an average o~ 12 ethylene oxide units per molecule and having an average molecular weight of 690) was used as monomer (A), 74.6 parts of sodium salt of 2-sul~oethyl acrylate (having a molecular weight of 202) was used as monomer (B), 17.6 parts of sodium acrylate (having a molecular weight of 94) was used as monomer (C), and the amount of ammonium persulfate was changed to 2.5 parts and that of sodium hydrogen sulfite to 1.2 parts.
Referential Example 15 In the same reaction vessel as used in Referential Example 1, 100 par~s of toluene placed therein was stirred and the inner yas of the reaction vessel was displaced with nitrogen. Then, in an atmosphere of nitrogen the toluene was heated to 100C. Subsequently to the hot toluene kept at this temperature, a monomer mixture solution containing 8.8 parts of isopropoxypolypropylene glycol methacrylate (containing an average of 3 propylene oxide units per molecule and having an average molecular weight of 302) as monomer (A), 53.8 parts of 2-sulfoethyl methacrylate (having a molecular weight of 194) as monomer (B), 31.3 parts of crotonic acid ~having a molecular weight of 86) as monomer (C), 6.1 parts of styrene (having a molecular weight of 104) as monomer (D), and 150 parts of toluene was added dropwise through one of the dropping funnels over a period of 120 i~ minutes. At the same time, a mixture containing 3 parts of ` benzoyl peroxide and 50 parts of toluene was added dropwise through the other dropping funnel over a period of 150 minutes. After the dropwise addition was completed, ::`
polymerization already initiated was continued at the same temperature for 60 minutes. Then, the polymerization mixture was distilled to expel toluene and obtain a ~, copolymer. This copolymer was dissolved in 300 parts of water and neutralized with 43.6 parts of an aqueous 25%

. .
; 30 . .
.

.

" 1 328 1 43 ammonia solution. Consequently, there was obtained a copolymer (15) having an average molecular weight of 10,000.
Referential Example 16 In the same reaction vessel as used in Referential Example 1, 100 parts of isopropyl alcohol (hereinafter referred to as "IPA") placed therein was stirred and the inner gas of the reaction vessel was displaced with nitrogen. Then in an atmosphere of nitrogen the IPA was heated to the boiling point thereof. Then, to the IPA which was kept refluxed, a monomer mixture solution containing 0.8 part of naphthoxypolyethylene glycol methacrylate ~contain-ing an average of 5 ethylene oxide units per molecule and having an average molecular weight of 432) as monomer (A), 84.6 parts of 2-sulfoethyl methacrylate (having a molecular weight of 194) as monomer (B), 14.6 parts of methacrylic acid lhaving a molecular weight of 86) as monomer (C), and 150 parts of IPA was added dropwise through one of the dropping funnels over a period of 120 minutes. At the same time, a mixture containing 0.7 part of azo bis-isobutyronitrile and 50 parts o~ IPA was added dropwise through the other dropping funnel over a period of 120 minutes. After the dropwise addition was completed, I polymerization already initiated was continued under reflux of IPA for 60 minutes. Then, the polymerization mixture was distilled to expel IPA and obtain a copolymer. The copolymer was dissolved in 300 parts of water and the resulting solution was neutralized with 24.2 parts of sodium j hydroxid , to afford a copolymer (16) having an average molecular weight of 130,000.
Referential Example 17 A control copolymer (1) having an average molecular weight of 40,000 was obtained by following the procedure of ~`j Referential Example 1, excepting use of monomer (A) was 0 I omitted, 59.6 parts of ammonium salt of 2-sulfoethyl~, acrylate (having a molecular weight of 197) was used as monomer (B), 40.4 parts of ammonium acrylate (having a .. :

- . .
,', :', " 1 328 1 ~3 molecular weight of 89) was used as monomer (C), and the amount of ammonium persulfate was changed to 1.5 parts.
Referential Example 18 A control copolymer ~2) having an average molecualr weight of 150,000 was obtained by following the procedure of Referential Example 1, excepting 0.3 part of methoxypolyethylene glycol methacrylate (containing an average of 15 ethylene oxide units per molecule and having an average molecular weight of 760) was used as monomer (A), 39.9 parts of sodium salt of 2-sulfoethyl methacrylate (having a molecular weight of 216~ was used as monomer (B), 59.8 parts of sodium meth.acrylate (having a molecualr weight of 108) was used as monomer (C), and the amount of ammonium persulfate was changed to 0.5 part.
Referential Example 19 A control copolymer (3) was obtained by preparing a copolymer having an average molecular weight of 30,000 following the procedure of Referential Example 1, excepting 41.4 parts of phenoxypolyethylene glycol methacyrlate (containing an average of 15 ethylene oxide units per molecule and having an average molecular weight of 822) was used as monomer (A), 51.4 parts of monoethanol amine salt of 2-sulfoethyl methacrylate (having a molecular weight of 255) was used as monomer (B), 7.2 parts of methacrylic acid (having a molecular weight of 86) was used as monomer (C), and the amount of ammonium persulfate was changed to 2.0 parts, and subsequently neutralizing the copolymer with 5.7 parts of an aqueous 25% ammonia solution.
Referential Example 20 A control copolymer (4) having an average molecualr weight of 50,000 was obtained by following the procedure of Referential Example 1, excepting 13.1 parts of p-methylphenoxypolyethylene glycol methacrylate (containing an average of 10 ethylene oxide units per molecule and having an average molecular weight of 616) was used as monomer (A), 1.9 parts of sodium salt of 2-sulfoethyl methacrylate (having a molecular weight of 216) was used as monomer (B), 85.0 parts of ammonium methacrylate (haivng a molecular weight of 103) was used as monomer (C), and the amount of ammonium persulfate was changed to 2.0 parts.
Referential Example 21 A control copolymer (5) having an average molecular weight of 150,000 was obtained by following the procedure of Referential Example 1, excepting 19.9 parts of ethoxypolyethylene glycol acrylate (containing an average of 45 ethylene oxide units per molecule and having an average molecular weight of 2,080) was used as monomer (A), 79.7 parts of sodium salt of 2-sulfoethyl methacrylate (having a molecular weight of 216) was used as monomer (B), 0.4 part of sodium methacrylate (having a molecular weight of 108) : was used as monomer (C), and the amount of ammonium . persulfate was changed to 0.5 part.
Referential Example 22 A control copolymer (6) having an average . molecular weight of 30,000 was obtained by following the procedure of Referential Example 1, excepting use of monomer (A) was omitted, and 58.7 parts of ammonium salt of 2-sulfoethyl acrylate (having a molecular weight of 197) was .l used as monomer (B), 40.3 parts of ammonium acrylate (having a molecular weight of 89) was used as monomer (C), and 1.0 part of polyethylene glycol monomethacrylate (containing an . average of 3 ethylene oxide units per molecule and having an average molecular weight of 218) was used as monomer (D), and the amount of ammonium persulfate was changed to 2.0 parts.
Tabla 1 shows the compositions (molar ratios) of the monomers (A), (B), (C), and (D) used in Referential Examples 1-22 and the average molecular weights of the . copolymers (1) through (16) and the control copolymers (1) through (6) obtained respectively threrein~
The average molecular weights of the copolymers were determined by the GPC method using polyethylene glycol ; as the standard.

.

. ' . . ::, .:; ~ . .
;: .
` , " -~

`` 1 328 1 ~3 Table 1 Monomer composition Average Referential Copolymer (mol %) molecular Example obtained (A)/(B)/(C)/(D)welqht 1 (1) ~.5/69/30.5/060,000 2 (2) 1/39/60/0 ~0,000 3 (3) 0.5/85/14.5/0200,000 4 (4) 0.8/50/47.2/260,000 (5) 0.2/39~8/60/0150,000 6 (6) 1/20/79/0 30,000 7 (7) 0.8/16.2/~3/070,000 : 8 (8) 2.5/12/85.5/020,000 9 (9) 0.6/36.2/63.2/060,000 (10) 0.8/39.2/60/0100,000 11 (11) 1.5/86.5/12/070,000 12 (12) 1/25/66/8 60,000 13 (13) 0.5/78/21.5/0150,000 . 14 (14) ~/65/33/0 20,000 :`. 15 (15) 4/38/50/8 10,000 16 (16) Q.3/71.7/28/0130,000 Control ' CopolYmer -~. 17 (1) 0/40/60/0 40,000 18 (2) 0.05/25/74.95/0150~000 , 19 (3) -15/60/25/0 30,~00 (4) 2.5/1/96.5/050,000 ` 21 (5) 2.5/96.5/1/0150,000 22 (6) 0/39.4/60/0.630,000 , .
., Examples 1-16 and Controls 1-8 ' An aqueous coal slurry was prepared by the following procedure using each of the copolymers ~1) through (16) obtained in Referential Examples 1-16, as a dispersant.
The viscosity of this aqueous coal slurry was measured.
In a ball mill having an inner volume of 6 liters and 30~ ball charge, an aqueous solution containing a given ;

' . : ., ' .. ,, ., .. ::
:

1 3~8 1 43 copolymer and coal A (having the quality shown in Table 2) coarsely crushed into grains about 2 mm in diameter was placed in an amount prescribed to give 2,000 g of a finished slurry and subjected therein to wet pulverization to prepare an aqueous coal slurry containing coal particles of diameters such that 83 +3% by weight of all the particles passed a 200-mesh sieve (not mroe than 74 ~m).
The viscosity of the aqueous coal slurries thus obtained were measured with a Brookfield type viscometer (rotor No. 6, 50 rpm) at 25C.
The amount of the dispersant added, the concentration of coal, and the viscosity of the produced aqueous coal slurry were as shown in Table 3.
In this table 3, the lower viscosity means the higher flowability.
In order to compare with polymer (1) to (16), the control copolymers (1) through (6) obtained respectively in Referential Examples 17 through 22, sodium polyacrylate ~ (having an average molecular weight of 20,000), and a ; formaline condensate of nonylphenolethylene oxide adduct (having an average condensation degree of 4, containing an average of 100 ethylene oxide units per molecul~ of nonylphenol, and having an average molecular weight of ' 20,000) were similarly tested by the procedure described ;'~ above. The results are also shown as those of ~ontrols 1-8 ;i in Table 3.
Examples 17-32 and controls 9-16 Aqueous coal slurries were prepared by faithfully repeating the procedures of Examples 1-16 and controls 1-8, excepting coal B (having the quality shown in Table 2) was used instead of coal A. The viscosity of the aqueous coal slurries were measured.
The amount of the dispersant added, the concentration of coal, and the viscosity of the prepared aqueous coal slurry were as shown in Table 3.
i Examples 33-48 and controls 17-24 ~ .
.:
:

Aqueous coal slurries were prepared by faithfully repeating the procedures of Examples 1-16 and Controls 1-8, excepting coal C (having the quality shown in Table 2) was used instead. The viscosity of the aqueous coal slurries were measured.
The amount of the dispersant added, the concent-raiton of coal, and the viscosity of the prepared aqueous coal slurry were as shown in Table 3.

Table 2 ~' .
Base of Item indication Coal A Coal B Coal C
_ ; Gross calorific value (Kcal/Kg) Wet Basis6,900 7,900 7,400 Inherent moisture content (%) " 3.2 4.5 1.5 Ash content (%) " 12.6 0.7 14.0 Volatile content (%) " 30.8 35.8 37.8 Fixed carbon (%) " 53.4 59.0 46.7 Fuel ratio - 1.73 1.65 1.24 (Elementary analysis) Ash content (%)Dry Basis13~0 0.7 14.2 Carbon (~) " 74.6 81.0 70.9 Hydrogen (%) " 4.6 4.9 5.2 !j Oxygen (%) " 5.5 11.4 5.8 (Ash composition~

Si2 (%) Dry Basis76.6 64.1 39.3 (%) ~ 15.2 18.5 21.5 CaO (%) " 0.9 2.2 14.3 MgO (%) " 0.4 1.9 0.9 Na2o (%) " 0-3 1.6 3-3 K2O (%) " 0.7 0.5 0.5 23 (%) ~ 3.0 7.5 8.8 , --~` ' ' ' . .

1 328 1 ~3 Table 3 -Amount of Concentration Viscosity Dispersant Coal dispersant oE coal ~% by of slurry E~ample usedused used (% by weight, based (cps) weight, based on slurry) _ on slurry) 1 copolymer (1) Coal A 0.3 68.0 1,500 2 " (2) " 0.3 68.01,600 3 " (3) " 0.4 66.01,600 4 " (4) " 0.3 68.01,4~0 " (5) " 0.5 67.01,700 6 " (6) " 0.3 69.01,40~
7 " (7~ " 0.4 68.01,600 8 " (8) " 0.5 68.01,500 9 " (9) " 0.4 69.01,600 " (10) " 0.5 67.01,400 11 " (11) " 0.5 68.01,500 12 " (12) " 0.5 67.01,700 13 " (13) " 0.4 68.01,~00 14 " (14) " 0.3 69.01,700 , 15 " (15) " 0.4 67.01,800 16 " (16) " 0.3 68.01,600 Control Control , 1 copolymer (1) Coal A 0.7 66.0 >10,000 2 " ~2) " 0.7 66.0>10,000 3 1l ( 3) " 0.7 66.0>10,000 " (4) " 0-5 66.03,000 " (5) " 0.5 66.02,500 6 " (6) " 0.5 66.02,800 7(Note 1) " 1.0 62.0>10,000 ; 8(Note 2~ " 0.6 66.0>10,000 : -37~-Table 3 (Continued 1) Amount of Concentration Viscosity DispersantCoal dispersant of coal (~ by of slurry Example usedused used (% by weight, based ( Cp5 ) weight, based on slurry) 17 copolymer (1) Coal B 0.368.0 1,500 18 " (2) " 0.3 69.01,600 19 " (3) " 0.4 68.01,800 . 20 " (4) " 0.3 68.01,400 . 21 " (5) " 0.4 69.01,700 22 " (6) " 0.4 71.01,600 23 " t7) " 0.4 70.0l,S00 24 " (8) " 0.5 71.01,600 " (9) " 0.4 70.01,800 ` 26 " (10) " 0.5 68.01,600 . 27 " (11) " 0.5 68.01,800 28 " (12) " 0.4 68.01,600 29 " (13) " 0.4 67.01,500 " (141 " 0.3 69.01,700 , 31 " (15) " 0.4 68.01,700 32 " (16) " 0.3 68.01,500 ~' Control ~: Control , 9 copolymer (1) Coal B 0.767.0 >10,000 : 10 " (2) " 0.7 67.0>10,000 11 " (3) " 0.7 67.0>10,000 ; 12 " (4) " 0.5 67.02,500 13 " (5) " 0.5 67.0>10,000 14 " (6) " 0.5 67.03,000 15(Note 1) " 1.0 62.0>10,000 16(Note 2) " 0.7 67.0>10,000 - ~ ' :
' --' 1 328 1 43 Table 3 tContinued 2) Amount of Concentration Viscosity DispersantCoal dispersant of coal (% by of slurry Example usedused used (% by weight, based (cps) weight, based on slurry) 33 copolymer (1) Coal C0.3 69.01,600 34 " (2) " 0.4 70.01,600 .. (3) ~ 0.5 70.01,500 36 " (4) " 0.3 69.01,800 : . 37 " (5) " 0.4 69.01,600 38 " (6) ". 0.5 70.01,800 39 . " (7) " 0.4 69.01,600 " (8) " 0.5 5g.01,800 41 " (9) " 0.4 70.01,900 42 " (10) " 0.5 69.01,600 43 " (11) " 0.5 71.0~,700 44 " (12) 1l 0.4 69.01,500 " (13) " 0.3 71.01,800 . 46 " (14) ll 0.3 70.01,500 47 " (15) 1l 0.4 70.01,800 48 " (16) " 0.4 71~01,600 Control Control 17 copolymer (1) Coal C0.7 69.0>10,000 18 ~ (2) 1l 0.7 69.0>10,000 19 " (3) " 0.7 69.0>10,000 " (4) ll 0.7 66.0>10.000 21 11 (5) 11 0.5 68.02,400 ` 22 11 (6) 11 0.5 69.0>10,000 23 (Note 1) ll 1.0 62.0>10,000 ~ 24 (Note 2) " 0.7 68.0>10,000 :~.
(Note 1) Sodium salt of polyacrylic acid (having an average ~ molecular weight of 20,000) (Note 2) Formalin condensate of nonylphenol-ethylene oxide adduct (having an average condensation degree of 4, containing an average of 100 ethylene oxide units per molecule of nonyl phenol, and having an average molecular weight of 20,000).

' , .

Examples 49-55 A portion, 300 g , of each of the aqueous coal slurry using coal A in Examples 1, 5, 6, 8, 10, 14, and 16 was diluted with water to a viscosity of 10 +1 poises. The sample thus prepared was placed and left standing in a cylindrical vessel 1 designed as illustrated in Fig. 1. At prescribed intervals of time, slurry portions, about 1 g each, were taken from the upper and lower layers of the sample respectively through outlets 2 and 3 and analyzed for coal concentration, to determine the degree of sedimenta-tion of the aqueous coal slurry and evaluate the stability of the slurry in standing. In Fig. 1, the aqueous coal slurry is shown as the number 4 and the dimension figures are given by the denomination of mm.
The initial concentration of coal, the kind of dispersant, the amount of dispersant added, and the stability of the slurry in the vessel are as shown in Table 4. The stability of the aqueous coal slurry in standing was determined by the duration of stability of this slurry, namely the period in which the difference of concentration between the two specimens taken simultaneously from the upper and lower layers of the sample was within 2% by weight. This duration of stability is expressed on a four-point scale, wherein A stands for a period of not less than 2 months, B for a period of not less than 1 month and less than 2 months, C for a period of not less than 1 week and less than 1 month, and D for a period of less than 1 week.
Examples 56-85 The stabilizing agent and/or the dispersion aid were added into the aqueous coal slurries which were found to be deficient in stability (denoted as B, C, or D) based on the results obtained Examples 49-55. And then the stability was tested by the ollowing procedure.
A sample, 300 g, taken from each of the aqueous coal slurries obtained by following the procedure of - . .
.
: :

Examples 6, 8, and 10 and a stabilizing agent and/or a dispersion aid and diluting water added thereto in amounts indicated in Table 4 were stirred using a homomixer (produced by Tokushukika Kogyo Co., Ltd. and marketed under trademark designation of "T. K. Auto-homomixer, Type M") at a rate of 5,000 rpm for 5 minutes. Consequently, there was produced an aqueous coal slurry having a viscosity of 10 +1 poises. The aqueous coal slurries consequently obtained were each tested for stability by the procedure of Example 49.
The intial concentration of coal in the aqueous coal slurry, the kind of dispersant, the amount of dispersant added, the kind of stabilizing agent additionally used, the amount of stabilizing agent added, the kind of dispersion aid additionally used, the amount of dispersion aid added, and the stability of the slurry are as shown in Table 4.

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1 328 1 ~3 Examples 86-100 A portion, 300 g, of each of the aqueous coal slurries obtained using coal B in Examples 17, 21, 22, 24, 26, 30, and 32 and a stabilizing agent and/or a dispersion aid and diluting water added thereto in amounts indicated in Table 5 were stirred at a rate of 5,000 rpm for five minutes using a homomixer (produced by Tokushukika Kogyo Co., Ltd.
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The aqueous coal slurries thus obtained were each tested for stability by the procedure of Example 49.
The initial concentration of coal in the aqueous coal slurry, the kind of dispersant, the amount of dispersant added, the kind of stabilizing agent additionally used, the amount of stabilizing agent added, the kind of dispersion aid additionally used, the amount of dispersion aid added, and the stability of the slurry are as shown in Table 5.
Example 101-104 A portion, 300 g, of each of the aqueous coal slurries obtained using coal C in Examples 38 and 40 and a ; stabilizing agent and/or a dispersion aid and diluting water added there~o in amounts indicated in Table 5 were stirred at a rate of 5,000 rpm for five minutes using a homomixer (produced by Tokushukika Kogyo K.R. and marketed under trademark designation of "T. K. Autohomomixer, Type M), to produce an aqueous coal slurry having a viscosity of 10 +1 poises.
The aqueous coal slurries thus obtained were each tested for stability by the procedure of Example 49.
The initial concentration of coal in the aqueous coal slurry, the kind of dispersant, the amount of dispersant added, the kind of stabilizing agent additionally ! used, the amount of stabilizing agent added, the kind of dispersion aid additionally used, the amount of dispersion ;

: -45-~ 1 328 1 43 , aid added, and the stability of the slurry are as shown in Table 5.
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Examples 105-108 Aqueous coal slurries were prepared by following the procedure of Example 1, excepting coal D (having the quality shown in Table 6) coarsely crushed into particles about 2 mm in diameter and aqueous solutions of the copolymers (2), (5), (7), and (14) added thereto as dispersant in amounts calculated to give 2,000 g of finished slurry were used. The viscosity of these aqueous coal slurries was measured by following the procedure of Example 1 to determine their flowability. Their pH value was also measured.
The concentration of coal in the aqueous coal slurry, the kind of dispersant used, the amount of dispersant added, and the pH value and viscosity of the slurry are as shown in Table 7.
Examples 109-115 Aqueous coal slurries were prepared by following the procedure of Example 1, excepting coal D (having the quality shown in Table 6) coarsely crushed into particles about 2 mm in diameter and aqueous solutions containing dispersants and pH adjusting agents as shown in Table 7 and added thereto in amounts calculated to give 2,000 g of finished slurry were used. The viscosity of the aqueous coal slurries was measured by following the procedure of Example 1 to determine their flowability. The pH value was also measured.
The concentration of coal in the aqueous coal slurry, the kind of dispersant used, the amount of dispersant added, the kind of pH adjusting agent, the amount of pH adjusting agent added, and the pH value and viscosity of the aqueous coal slurry obtained are as shown in Table 7.
~' ~, ~ ' ' ' ' ' `' Table 6 Analys i s Item Base of indication Coal D
Gross calorific value (Kcal/Kg) Wet Basis 6~700 Inherent moisture " 3.4 content (%) Ash Content (~) " 13.1 Volatile content (%) " 26.1 Fixed carbon (%) " 57-4 Fuel ratio -------- 2.20 (Elementary analysis) Ash Content (%) Dry Basis 13.6 Carbon (%) " 74.1 Hydrogen (~) " 4.4 i OXygen (%) "

( Ash composition) 2 (%) Dry Basis 51.8 ; A12O3 35.6 CaO (%) " 2 0 MgO (%) ll 0 6 Na2o t%) 0-4 F-203 (~) 4.8 ;

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INDUSTRIAL APPLICATION
The dispersant for an aqueous carbonaceous solid slurry according with the present invention e~cels in ability to disperse of a carbonaceous solid, particularly coal, in water. By the addition of this dispersant only in a small amount, there can be produced an aqueous carbonaceous solid slurry of high flowability in a highly concentrated form.
Conveyance of a given carbonaceous solid via a pipeline can be accomplished with high economy by converting this carbonaceous solid into an aqueous slurry by the use of the dispersnat of this invention. Thus, the present invention offers a solution to the problem encountered in the transportation and combustion of carbonaceous solids.
The dispersant of the present invention for an aqueous carbonaceous solid slurry, therefore, contributes immensely to the propagation of techniques for utility of carbonaceous solids such as direct combustion and gasification.
Particularly the dispersant of this invention manifests its dispersion ability to various kind of a carbonaceous solid without reference to the ash content, the water content, and the chemical composition thereof.
The dispersant of this invention can be used, in combination with a polymer, a surfactant, or an inorganic powder as a dispersion aid or a stabilizing agent. It, therefore, permits easy production of an aqueous carbonaceous solid slurry composition which has not only a high solid content and high flowability but also stability against sedimentation of solid partcles for long period.

Claims (21)

1. A dispersant for an aqueous carbonaceous solid slurry, comprising a water-soluble copolymer having an average molecular weight of 1,000 to 500,000 prepared by polymerizing monomer components (A), (B) and (C), wherein said monomer components (A), (B) and (C) are selected respectively from the groups:

(A) 0.1 to 7 mol% of a polyalkylene glycol mono(meth) acrylate type monomer represented by the general formula I:

(I) wherein R1 stands for hydrogen atom or methyl group, R2 for alkylene group having 2 to 4 carbon atoms, n for a numeral in the range of 1 to 100 on the average, and R3 for an alkyl, alkenyl, aryl, aralkyl, cyclic alkyl or cyclic alkenyl group having 1 to 30 carbon atoms, or a monovalent organic group having 4 to 30 carbon atoms derived from a heterocyclic compound, (B) 5 to 94.9 mol% of a sulfoalkyl (meth)acrylate type monomer represented by the general formula II:

(II) wherein R4 stands for hydrogen atom or methyl group, R5 for alkylene group having 1 to 4 carbon atoms and X for hydrogen atom, an alkali metal atom, an alkaline earth metal atom, an ammonium group, or an amine base; and (C) 5 to 94.9 mol% of an unsaturated carboxylic acid type monomer represented by the general formula III:

(III) wherein R6 and R7 independently stand for a hydrogen atom, methyl group, or -COOY, providing that R6 and R7 do not simultaneously stand for -COOY, R8 stands for hydrogen atom, methyl group, -COOY, or -CH2COOY providing that R6 and R7 independently stand for hydrogen atom or methyl group where R8 stands for -COOY or -CH2COOY, and Y stands for a hydrogen atom, alkali metal atom, alkaline earth metal atom, group, or amine base, providing that the total amount of the monomer components (A), (B) and (C) is 100 mol%.

2. A dispersant as claimed in claim 1, wherein a monomer component (D) is polymerized with monomer components (A), (B) and (C), said monomer component (D) is represented by up to 20 mol% of:
i) alkyl (meth)acrylates, ii) sulfonic acids other than said sulfonic acids of mononer (B), iii) alkali metal salts, alkaline earth metal salts, ammonium salts, organic amine salts of said acids of group (ii), iv) hydroxyl containing monomers of alkyl (meth)acrylates, v) (meth)acrylamides, vi) aromatic vinyl monomers, or vii) vinyl acetate, propenyl acetate and vinyl chloride.

3. A dispersant of claim 1 which has an average weight in the range of 5,000 to 300,000.

4. A dispersant as claimed in claim 2 which has an average molecular weight in the range of from 5,000 to 300,000.

5. A dispersant as claimed in claim 1, wherein said unsaturated carboxylic acid type monomer (C) is at least one member selected from the group consisting of maleic acid, (meth)acrylic acid, and alkali metal salts, alkaline earth metal salts, ammonium salts and amine salts thereof.

6. A dispersant as claimed in claim 5, wherein said unsaturated carboxylic acid type monomer (C) is at least one member selected from the group consisting of maleic acid and (meth)acrylic acid and sodium salts, potassium salts, ammonium salts, and alkanolamine salts of said acids.

7. A dispersant as claimed in claim 6, wherein said alkanolamine salts of maleic acid and (meth)acrylic acid are monoethanolamine salts, diethanolamine salts, or triethanolamine salts.

8. A dispersant as claimed in claim 1 wherein R1 stands for a hydrogen atom or methyl group, R2 for an ethylene group or a propylene group, n for a numeral in the range of from 2 to 50 on the average, and R3 for alkyl, phenyl, or naphthyl group having 1 to 20 carbon atoms or alkylphenyl or benzyl group possessing 1 to 3 alkyl groups each of 1 to 10 carbon atoms as a substituent thereof.

9. A dispersant as claimed in claim 1 wherein R2 in said general formula I stands for an ethylene group; and/or R3 in said general formula I stands for a methyl group, ethyl group, propyl group, isopropyl group, octyl group, phenyl group, naphthyl group, methylphenyl group, dimethylphenyl group, nonylphenyl group, dinonylphenyl group, octylphenyl group, dioctylphenyl group, or benzyl group.

10. A dispersant as claimed in claim 1, wherein R4 stands for a hydrogen atom or methyl group, R5 for an ethylene group or propylene group, and X for a hydrogen atom, sodium atom, potassium atom, ammonium group, or alkanolamine base.

11. A dispersant as claimed in claim 10, wherein said alkenolamine base is selected from the group consisting of monoethanolamine, diethanolamine and triethanolamine.

12. A dispersant as claimed in any one of claims 1, 2, 3, 4, 5 or 6 wherein said monomer components are used in proportions such that the amounts of said monomer (A) falls in the range of 0.2 to 5 mol%, that of said monomer (B) in the range of 10 to 89.8 mol%, that of said monomer C) in the range of 10 to 89.8 mol%, and that of said monomer; (D) up to 10 mol%, providing that the total amount of said monomers (A), (B), (C) and (D) is 100 mol%.

13. A dispersant of any one of claims 1, 2, 3, 4, 5, 6, 7, 8, 9 or 11, wherein said water-soluble copolymer is neutralized with a base.

14. An aqueous carbonaceous solid slurry composition, comprising an aqueous carbonaceous solid and a dispersant as claimed in claim 1.

15. A composition as claimed in claim 14, wherein said carbonaceous solid is at least one member selected from the group consisting of coal, coke and pitch.

16. A composition as claimed in claim 14, wherein the carbonaceous solid content in said composition falls in the range of 40 to 90% by weight.

17. A composition as claimed in claim 14, further comprising a dispersion aid in an amount in the range of 0.01 to 5 parts by weight, based on 100 parts by weight of said carbonaceous solid.

18. A composition as claimed in claim 17, wherein said dispersion aid is a polystyrene sulfonic acid or salts thereof, a styrene-styrene sulfonic acid copolymer or salts thereof, sulphonated naphthalene or creosote oil or salts thereof, aliphatic aldehyde condensates of sulphonate group-containing aminotriazines, or salts thereof, compounds containing a tricyclodecane or tricyclodecene skeleton and a sulphonate group in the molecular unit thereof, or polyether compounds obtained by adding alkylene oxides to formalin condensates of alkylphenols.

19. A composition as claimed in claim 14, further comprising a stabilizing agent formed of at least one compound selected from the group consisting of clay minerals, polysaccharides, and alkali metal salts of polyacrylic acid.

20. A composition as claimed in claim 19, wherein said polysaccharides are sodium salts of carboxymethyl cellulose and hydroxyethyl cellulose, and/or said alkali metal salt of polyacrylic acid is sodium polyacrylate.

21. A composition as claimed in any one of claims 14, 15, 16, 17, 18, 19 or 20 further comprising a pH
adjusting agent formed of at least one basic substance, selected from the group consisting of hydroxides, oxides, and carbonates of alkali metals, hydroxides, oxides, and carbonates of alkaline earth metals, ammonia and organic amines is used in an amount in the range of 0.01 to 5 part by weight, based on 100 parts by weight of said carbonaceous solid.