Coal dressing compound collecting agent and preparation method thereof

Abstract

The invention discloses a coal dressing compound collecting agent and a preparation method thereof. The coal dressing compound collecting agent comprises the following raw materials in parts by weight: 100 parts of non-polar hydrocarbon oil, 10-50 parts of fatty acid and 1-10 parts of a surfactant, wherein the surfactant is prepared from 2-hexadecyl octadecanoic acid amido betaine and a quaternized guar gum high-molecular surfactant, and the surfactant is prepared from the following raw materials in parts by weight; the non-polar hydrocarbon oil is one or more of diesel oil, paraffin oil, poly-alpha-olefin, cyclohexene and C10-C20 olefin; the fatty acid is one or more of stearic acid, oleic acid, octanoic acid, palmitic acid and lauric acid. The coal dressing compound collecting agent can form a more stable structure with low-rank coal under the action of acting force such as hydrogen bonds, so that the collecting performance of the collecting agent on the low-rank coal is improved, and the yield of clean coal is increased.

Description

Technical Field

[0001] The present invention relates to the technical field of coal preparation, and in particular to a composite collector for coal preparation and a preparation method thereof. Background Art

[0002] Low-rank coal, such as lignite and low-quality bituminous coal, typically has high ash, sulfur, and moisture contents, low volatile matter, and low calorific value, making it difficult to meet the requirements for efficient combustion. Therefore, flotation upgrading of low-rank coal has become an important means to increase its economic value and utilization rate.

[0003] Flotation upgrading utilizes the differences in hydrophilicity and hydrophobicity of mineral surfaces to separate coal from impurities (such as mineral impurities, ash, and sulfur) using bubbles to increase coal purity and calorific value. Collectors and frothers play a crucial role in the flotation process.

[0004] Coal preparation collectors (also called flotation collectors) are chemical additives used in the coal flotation process. Their primary function is to promote the flotation separation of coal particles. They modify the surface properties of coal particles, allowing them to bind with air bubbles during flotation, thereby floating to the surface of the slurry and separating the coal from impurities. Existing coal preparation collectors primarily target non-polar hydrocarbon oils such as kerosene, diesel, natural gas condensate, and fuel oil. The present invention aims to provide a new coal preparation collector. Summary of the Invention

[0005] Based on the technical problems existing in the background technology, the present invention proposes a composite coal preparation collector and a preparation method thereof, which improves the yield of clean coal.

[0006] The present invention provides a composite coal preparation collector comprising the following raw materials in parts by weight: 100 parts of non-polar hydrocarbon oil, 10-50 parts of fatty acid, and 1-10 parts of surfactant; The surfactant is composed of 2-hexadecyl octadecanoic acid amide betaine and quaternized guar gum high molecular surfactant in a mass ratio of 3:1-9.

[0007] Preferably, the non-polar hydrocarbon oil is one or more of diesel, paraffin oil, poly-α-olefin, cyclohexene, and C10-C20 olefin.

[0008] Preferably, the fatty acid is one or more of stearic acid, oleic acid, caprylic acid, palmitic acid and lauric acid.

[0009] The preparation method of the composite collector for coal preparation proposed by the present invention comprises the following steps: S1: Preparation of 2-hexadecyl octadecanoic acid amide betaine and quaternized guar gum polymer surfactant; S2: Evenly mix the non-polar hydrocarbon oil, fatty acid and surfactant to prepare a coal preparation compound collector.

[0010] Preferably, the steps of the method for preparing 2-hexadecyl octadecanoic acid amide betaine are as follows: S11: reacting 2-hexadecanoic acid and N,N-dimethyl-1,3-propylenediamine in a reactor to obtain an intermediate 2-hexadecanoic acid amidopropyl tertiary amine; S12: reflux 2-hexadecyl octadecanoic acid amide propyl tertiary amine and sodium chloroacetate solution for 5-10 hours, and obtain 2-hexadecyl octadecanoic acid amide betaine after separation and purification.

[0011] Preferably, the molar ratio of 2-hexadecanoic acid to N,N-dimethyl-1,3-propylenediamine in S11 is 1:1-1.2; the reaction temperature is 150-180° C., and the reaction time is 6-12 h.

[0012] Preferably, the molar ratio of 2-hexadecyloctadecanoic acid amide propyl tertiary amine to sodium chloroacetate in S12 is 1:1-1.1; the mass fraction of the sodium chloroacetate solution is 20-40%, and the solvent is a mixture of water and ethanol in a volume ratio of 1:1.

[0013] Preferably, the method for preparing the quaternized guar gum polymer surfactant comprises the following steps: dispersing guar gum in isopropyl alcohol, then adding (3-chloro-2-hydroxypropyl) dodecyldimethylammonium chloride, and reacting under the catalysis of potassium hydroxide to obtain the quaternized guar gum polymer surfactant.

[0014] Preferably, the mass ratio of guar gum, (3-chloro-2-hydroxypropyl) dodecyldimethylammonium chloride and potassium hydroxide is 1:2-4:0.01-0.05.

[0015] Preferably, the reaction temperature is 60-80°C and the reaction time is 2-4 hours.

[0016] Beneficial technical effects of the present invention: The coal preparation composite collector of the present invention is composed of non-polar hydrocarbon oil, fatty acid and surfactant. During the flotation process of low-rank coal, the coal preparation composite collector can form a more stable structure with the low-rank coal under the action of forces such as hydrogen bonds, thereby improving the collector's collection performance for low-rank coal and increasing the yield of clean coal. In addition, the surfactant of the present invention is composed of 2-hexadecyl octadecanoic acid amide betaine and quaternized guar gum polymer surfactant, which has a synergistic promoting effect on improving the collection performance of the collector, thereby ensuring the high clean coal yield of the collector of the present application during the flotation process. DETAILED DESCRIPTION

[0017] The present invention will be further explained below with reference to specific embodiments.

[0018] Example 1 The present invention provides a composite coal preparation collector comprising the following raw materials in parts by weight: 100 g diesel, 20 g stearic acid, 10 g octanoic acid, and 5 g surfactant; The surfactant is composed of 2-hexadecyl octadecanoic acid amide betaine and quaternized guar gum high molecular surfactant in a mass ratio of 1:1.

[0019] The preparation method of the composite collector for coal preparation proposed by the present invention comprises the following steps: S1: Preparation of 2-hexadecyl octadecanoic acid amide betaine and quaternized guar gum polymer surfactant; S2: Diesel oil, stearic acid, octanoic acid and surfactant are mixed evenly to prepare a composite collector for coal preparation.

[0020] The steps for preparing 2-hexadecyl octadecanoic acid amide betaine are as follows: S11: reacting 2-hexadecanoic acid and N,N-dimethyl-1,3-propylenediamine in a reactor to obtain an intermediate 2-hexadecanoic acid amidopropyl tertiary amine; S12: reflux 2-hexadecyl octadecanoic acid amide propyl tertiary amine and sodium chloroacetate solution for 8 hours, and obtain 2-hexadecyl octadecanoic acid amide betaine after separation and purification.

[0021] The molar ratio of 2-hexadecanoic acid to N,N-dimethyl-1,3-propylenediamine in S11 is 1:1.1; the reaction temperature is 165° C., and the reaction time is 9 h.

[0022] The molar ratio of 2-hexadecyloctadecanoic acid amide propyl tertiary amine to sodium chloroacetate in S12 is 1:1.05; the mass fraction of the sodium chloroacetate solution is 30%, and the solvent is a mixture of water and ethanol in a volume ratio of 1:1.

[0023] The method for preparing a quaternized guar gum high molecular surfactant comprises the following steps: dispersing guar gum in isopropyl alcohol, then adding (3-chloro-2-hydroxypropyl) dodecyldimethylammonium chloride, and reacting under the catalysis of potassium hydroxide to obtain a quaternized guar gum high molecular surfactant.

[0024] The mass ratio of guar gum, (3-chloro-2-hydroxypropyl) dodecyldimethylammonium chloride and potassium hydroxide is 1:3:0.03; the reaction temperature is 70° C. and the reaction time is 3 h.

[0025] Example 2 The present invention provides a composite coal preparation collector comprising the following raw materials in parts by weight: 60 g diesel, 40 g cyclohexene, 10 g lauric acid, and 1 g surfactant; The surfactant is composed of 2-hexadecyl octadecanoic acid amide betaine and quaternized guar gum high molecular surfactant in a mass ratio of 3:1.

[0026] The preparation method of the composite collector for coal preparation proposed by the present invention comprises the following steps: S1: Preparation of 2-hexadecyl octadecanoic acid amide betaine and quaternized guar gum polymer surfactant; S2: Diesel, cyclohexene, lauric acid and surfactant are mixed evenly to prepare a coal preparation compound collector.

[0027] The steps for preparing 2-hexadecyl octadecanoic acid amide betaine are as follows: S11: reacting 2-hexadecanoic acid and N,N-dimethyl-1,3-propylenediamine in a reactor to obtain an intermediate 2-hexadecanoic acid amidopropyl tertiary amine; S12: reflux 2-hexadecyl octadecanoic acid amide propyl tertiary amine and sodium chloroacetate solution for 5 hours, and obtain 2-hexadecyl octadecanoic acid amide betaine after separation and purification.

[0028] The molar ratio of 2-hexadecanoic acid and N,N-dimethyl-1,3-propylenediamine in S11 is 1:1; the reaction temperature is 150° C., and the reaction time is 12 h.

[0029] The molar ratio of 2-hexadecyloctadecanoic acid amide propyl tertiary amine to sodium chloroacetate in S12 is 1:1; the mass fraction of the sodium chloroacetate solution is 20%, and the solvent is a mixture of water and ethanol in a volume ratio of 1:1.

[0030] The method for preparing a quaternized guar gum high molecular surfactant comprises the following steps: dispersing guar gum in isopropyl alcohol, then adding (3-chloro-2-hydroxypropyl) dodecyldimethylammonium chloride, and reacting under the catalysis of potassium hydroxide to obtain a quaternized guar gum high molecular surfactant.

[0031] The mass ratio of guar gum, (3-chloro-2-hydroxypropyl) dodecyldimethylammonium chloride and potassium hydroxide is 1:2:0.01; the reaction temperature is 60° C. and the reaction time is 2 h.

[0032] Example 3 The present invention provides a composite coal preparation collector comprising the following raw materials in parts by weight: 100 g of paraffin oil, 50 g of stearic acid, and 10 g of a surfactant; The surfactant is composed of 2-hexadecyl octadecanoic acid amide betaine and quaternized guar gum high molecular surfactant in a mass ratio of 1:3.

[0033] The preparation method of the composite collector for coal preparation proposed by the present invention comprises the following steps: S1: Preparation of 2-hexadecyl octadecanoic acid amide betaine and quaternized guar gum polymer surfactant; S2: Evenly mix paraffin oil, stearic acid and surfactant to prepare a coal preparation compound collector.

[0034] The steps for preparing 2-hexadecyl octadecanoic acid amide betaine are as follows: S11: reacting 2-hexadecanoic acid and N,N-dimethyl-1,3-propylenediamine in a reactor to obtain an intermediate 2-hexadecanoic acid amidopropyl tertiary amine; S12: reflux 2-hexadecyl octadecanoic acid amide propyl tertiary amine and sodium chloroacetate solution for 10 hours, and obtain 2-hexadecyl octadecanoic acid amide betaine after separation and purification.

[0035] The molar ratio of 2-hexadecanoic acid to N,N-dimethyl-1,3-propylenediamine in S11 is 1:1.2; the reaction temperature is 180° C., and the reaction time is 12 h.

[0036] The molar ratio of 2-hexadecyloctadecanoic acid amide propyl tertiary amine to sodium chloroacetate in S12 is 1:1.1; the mass fraction of the sodium chloroacetate solution is 40%, and the solvent is a mixture of water and ethanol in a volume ratio of 1:1.

[0037] The method for preparing a quaternized guar gum high molecular surfactant comprises the following steps: dispersing guar gum in isopropyl alcohol, then adding (3-chloro-2-hydroxypropyl) dodecyldimethylammonium chloride, and reacting under the catalysis of potassium hydroxide to obtain a quaternized guar gum high molecular surfactant.

[0038] The mass ratio of guar gum, (3-chloro-2-hydroxypropyl) dodecyldimethylammonium chloride and potassium hydroxide is 1:4:0.05; the reaction temperature is 80° C. and the reaction time is 4 h.

[0039] Comparative Example 1 The present invention provides a composite coal preparation collector comprising the following raw materials in parts by weight: 100 g diesel, 20 g stearic acid, 10 g octanoic acid, and 5 g 2-hexadecyl octadecanoic acid amide betaine; The preparation method of the composite collector for coal preparation proposed by the present invention comprises the following steps: S1: Preparation of 2-hexadecanoyloctadecanoic acid amide betaine; S2: diesel, stearic acid, octanoic acid and 2-hexadecyl octadecanoic acid amide betaine are mixed evenly to prepare a coal preparation composite collector.

[0040] The steps for preparing 2-hexadecyl octadecanoic acid amide betaine are as follows: S11: reacting 2-hexadecanoic acid and N,N-dimethyl-1,3-propylenediamine in a reactor to obtain an intermediate 2-hexadecanoic acid amidopropyl tertiary amine; S12: reflux 2-hexadecyl octadecanoic acid amide propyl tertiary amine and sodium chloroacetate solution for 8 hours, and obtain 2-hexadecyl octadecanoic acid amide betaine after separation and purification.

[0041] The molar ratio of 2-hexadecanoic acid to N,N-dimethyl-1,3-propylenediamine in S11 is 1:1.1; the reaction temperature is 165° C., and the reaction time is 9 h.

[0042] The molar ratio of 2-hexadecyloctadecanoic acid amide propyl tertiary amine to sodium chloroacetate in S12 is 1:1.05; the mass fraction of the sodium chloroacetate solution is 30%, and the solvent is a mixture of water and ethanol in a volume ratio of 1:1.

[0043] Comparative Example 2 The invention provides a composite coal preparation collector comprising the following raw materials in parts by weight: 100 g diesel, 20 g stearic acid, 10 g octanoic acid, and 5 g quaternized guar gum polymer surfactant; The preparation method of the composite collector for coal preparation proposed by the present invention comprises the following steps: S1: Preparation of quaternized guar gum polymer surfactant; S2: diesel, stearic acid, octanoic acid and quaternized guar gum high molecular surfactant are mixed evenly to prepare a coal preparation compound collector.

[0044] The method for preparing a quaternized guar gum high molecular surfactant comprises the following steps: dispersing guar gum in isopropyl alcohol, then adding (3-chloro-2-hydroxypropyl) dodecyldimethylammonium chloride, and reacting under the catalysis of potassium hydroxide to obtain a quaternized guar gum high molecular surfactant.

[0045] The mass ratio of guar gum, (3-chloro-2-hydroxypropyl) dodecyldimethylammonium chloride and potassium hydroxide is 1:3:0.03; the reaction temperature is 70° C. and the reaction time is 3 h.

[0046] Low-rank coal was floated using the composite coal-washing collectors prepared in Examples 1-3 and Comparative Examples 1-2, wherein the addition amount of the composite coal-washing collector was 1.5 kg / t. Low-rank coal (ash content 31.42%) from a coal plant was floated, and the test results are shown in Table 1.

[0047] Table 1 Flotation results of low-rank coal It can be seen from the test results of Table 1 that the collector of the present invention can achieve excellent collection performance when added in an amount of 1.5 kg / t, thereby significantly improving the yield of clean coal. This is because in the presence of a surfactant, the coal preparation composite collector can form a more stable structure with low-rank coal through forces such as hydrogen bonds, thereby improving the collection performance of the collector for low-rank coal and improving the yield of clean coal; in addition, according to the test results of Example 1 and Comparative Example 1 and Comparative Example 2, it can be seen that the surfactant 2-hexadecyl octadecanoic acid amide betaine and the quaternized guar gum polymer surfactant of the present application have a synergistic promoting effect on improving the collection performance of the collector, thereby ensuring the high clean coal yield of the collector of the present application during the flotation process.

Claims

1. A composite collector for coal preparation, characterized in that: The raw materials include the following parts by weight: 100 parts of non-polar hydrocarbon oil, 10-50 parts of fatty acid, and 1-10 parts of surfactant; The surfactant is composed of 2-hexadecyl octadecanoic acid amide betaine and quaternized guar gum high molecular surfactant in a mass ratio of 3:1-9.

2. The composite coal preparation collector according to claim 1, characterized in that: The non-polar hydrocarbon oil is one or more of diesel, paraffin oil, poly-α-olefin, cyclohexene, and C10-C20 olefin.

3. The composite coal preparation collector according to claim 1, characterized in that: The fatty acid is one or more of stearic acid, oleic acid, caprylic acid, palmitic acid and lauric acid.

4. The method for preparing a composite collector for coal preparation according to any one of claims 1 to 3, wherein: The steps are as follows: S1: Preparation of 2-hexadecyl octadecanoic acid amide betaine and quaternized guar gum polymer surfactant; S2: Evenly mix the non-polar hydrocarbon oil, fatty acid and surfactant to prepare a coal preparation compound collector.

5. The method for preparing a composite collector for coal preparation according to claim 4, characterized in that: The steps for preparing 2-hexadecyl octadecanoic acid amide betaine are as follows: S11: reacting 2-hexadecanoic acid and N,N-dimethyl-1,3-propylenediamine in a reactor to obtain an intermediate 2-hexadecanoic acid amidopropyl tertiary amine; S12: reflux 2-hexadecyl octadecanoic acid amide propyl tertiary amine and sodium chloroacetate solution for 5-10 hours, and obtain 2-hexadecyl octadecanoic acid amide betaine after separation and purification.

6. The method for preparing a composite collector for coal preparation according to claim 5, characterized in that: The molar ratio of 2-hexadecanoic acid to N,N-dimethyl-1,3-propylenediamine in S11 is 1:1-1.2; the reaction temperature is 150-180° C., and the reaction time is 6-12 hours.

7. The method for preparing a composite collector for coal preparation according to claim 5, characterized in that: The molar ratio of 2-hexadecyloctadecanoic acid amide propyl tertiary amine to sodium chloroacetate in S12 is 1:1-1.1; the mass fraction of the sodium chloroacetate solution is 20-40%, and the solvent is a mixture of water and ethanol in a volume ratio of 1:

1.

8. The method for preparing a composite collector for coal preparation according to claim 4, characterized in that: The method for preparing a quaternized guar gum high molecular surfactant comprises the following steps: dispersing guar gum in isopropyl alcohol, then adding (3-chloro-2-hydroxypropyl) dodecyldimethylammonium chloride, and reacting under the catalysis of potassium hydroxide to obtain a quaternized guar gum high molecular surfactant.

9. The method for preparing a composite collector for coal preparation according to claim 8, characterized in that: The mass ratio of guar gum, (3-chloro-2-hydroxypropyl) dodecyldimethylammonium chloride and potassium hydroxide is 1:2-4:0.01-0.

05.

10. The method for preparing a composite collector for coal preparation according to claim 8, characterized in that: The reaction temperature is 60-80°C and the reaction time is 2-4 hours.

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