阅读说明：本技术 一种使用低品位凹凸棒黏土原矿制备脱色剂的方法 (Method for preparing decoloring agent by using low-grade attapulgite clay raw ore ) 是由 雍积全 王志梅 王惠善 于 2018-07-05 设计创作，主要内容包括：本发明涉及凹凸棒黏土加工技术领域,具体涉及一种使用低品位凹凸棒黏土原矿制备脱色剂的方法,具体步骤包括：选矿、破碎、加酸和粉磨工序。本发明工艺简单,节约成本,能使用凹凸棒石含量为20%～40%的低品位凹凸棒黏土原矿,生产出符合国家标准的脱色剂,填补了低品位凹凸棒黏土原矿生产脱色剂的技术空白。(The invention relates to the technical field of attapulgite clay processing, in particular to a method for preparing a decoloring agent by using low-grade attapulgite clay raw ore, which comprises the following steps: mineral separation, crushing, acid adding and grinding. The method has simple process and low cost, can produce the decolorant meeting the national standard by using the low-grade attapulgite clay raw ore with the attapulgite content of 20-40 percent, and fills the technical blank of producing the decolorant by using the low-grade attapulgite clay raw ore.)

1. A method for preparing a decoloring agent by using low-grade attapulgite clay raw ore comprises the following steps:

the method comprises the following steps: mineral separation, namely performing mineral separation treatment on low-grade attapulgite clay raw ore with the attapulgite content of 20-40% to remove gypsum and sandstone to form 100 parts of a pre-selected material H;

step two: crushing, namely crushing the pre-selected material H by using a crushing device to form crushed material K;

step three: adding acid, namely adding 20 to 45 parts of attapulgite clay solid acidifying agent into the crushed material K, and uniformly stirring to form a mixture L;

step four: grinding: the mixture L is ground to be 200 meshes in fineness, the passing rate is 80-90%, the water content is less than or equal to 10%, and the acid content is less than or equal to 0.2%, so that a finished product is prepared.

2. The method for preparing the decoloring agent by using the low-grade attapulgite clay raw ore according to claim 1, wherein the attapulgite clay solid acidifying agent in the third step consists of the following components in percentage by weight: SiO 2₂58 to 71 percent of Al₂O₃5.0-15% of Fe₂O₃1.5-5%, 0.2-5.5% of MgO, 0.5-4.5% of CaO, 2.5-11% of free acid and the balance of inevitable impurities.

3. The method for preparing a decoloring agent by using low-grade attapulgite clay raw ore according to claim 1 or 2, wherein 45 parts of attapulgite clay solid acidifying agent is added in the third step when the content of attapulgite in the low-grade attapulgite clay raw ore in the first step is 20%.

4. The method for preparing a decoloring agent by using low-grade attapulgite clay raw ore according to claim 1 or 2, wherein 32 parts of attapulgite clay solid acidifying agent is added in the third step when the content of attapulgite in the low-grade attapulgite clay raw ore in the first step is 32%.

5. The method for preparing a decoloring agent by using low-grade attapulgite clay raw ore according to claim 1 or 2, wherein 20 parts of attapulgite clay solid acidifying agent is added in the third step when the content of attapulgite in the low-grade attapulgite clay raw ore in the first step is 40%.

6. The method for preparing a decoloring agent by using low-grade attapulgite clay raw ore according to claim 1 or 2, wherein kaolinite, muscovite, dolomite, chlorite, illite and the like or montmorillonite are associated with the low-grade attapulgite clay raw ore.

7. The method for preparing the decoloring agent by using the low-grade attapulgite clay raw ore according to claim 2, wherein the attapulgite clay solid acidifying agent further comprises sulfur trioxide and loss on ignition in the composition.

8. The method for preparing the decoloring agent by using the low-grade attapulgite clay raw ore according to claim 2, wherein the method for preparing the attapulgite clay solid acidifying agent comprises the following steps:

the method comprises the following steps: crushing, namely mixing the bentonite ore and the attapulgite clay according to the proportion of 4: 1-2: 1, and crushing to form 30 parts of crushed material A;

step two: wet purification, namely putting the crushed material A into 100 parts of water, and adding 0.5-1 part of dispersant for wet purification to form a mixture B;

step three: adding acid, and putting 3-7.5 parts of sulfuric acid with the concentration of 98% into the mixture B to be uniformly stirred to form a mixture C;

step four: heating and acidifying, namely introducing steam to heat and acidify the mixture C, wherein the reaction temperature is 120-130 ℃, the reaction pressure is 0.2-0.3 MPa, and the reaction time is 2 hours to form a mixture D;

step five: washing with acid, filter-pressing, adding water to dilute the mixture D until the content of free acid is 2.5% -11%, and then filter-pressing and dehydrating to form a mixture E;

step six: cooling and drying, namely cooling the mixture E to room temperature, and then drying or sun-drying to form a mixture F, wherein the water content of the mixture F is less than or equal to 10%;

step seven: and grinding, namely grinding the mixture E to obtain a mixture with the fineness of 200 meshes and the passing rate of more than or equal to 90 percent to form a final finished product.

9. The method for preparing a decoloring agent by using low-grade attapulgite clay raw ore according to claim 8, wherein the dispersant in the second step of the preparation method of the attapulgite clay solid acidifying agent is sodium pyrophosphate, sodium hexametaphosphate or sodium silicate.

10. The method for preparing the decoloring agent by using the low-grade attapulgite clay raw ore according to claim 8, wherein in the step five of the preparation method of the attapulgite clay solid acidifying agent, acid water formed by filter pressing and dehydration of the mixture D can be conveyed to the step two for recycling.

Technical Field

The invention relates to the technical field of attapulgite clay processing, in particular to a method for preparing a decoloring agent by using low-grade attapulgite clay raw ore.

Background

The attapulgite clay has good decolorizing capacity when being used for producing the grease decolorizing agent, the activation process is simple, the raw materials are prepared by activation, solidification, modification, crushing and grading production, the impurities are not required to be removed, the tailings are not required to be removed, the rinsing and the deacidification are not required, the environmental pollution is avoided, the continuous production can be realized, and the production cost is low. But has high requirements on the grade of the attapulgite clay used for production, and the content of the attapulgite in the mineral components is at least more than 45 percent, even more than 50 percent.

At present, Xuyi and Liuhe high-quality attapulgite clay is mainly used for producing the grease decoloring agent by using attapulgite clay domestically. The Xuyi (Longwangshan) attapulgite clay comprises 70-80% of attapulgite, 5-10% of quartz, 10-25% of hydromica and montmorillonite and 2% of opal. The attapulgite clay mineral components of the Liuhe (white hills and small-pan mountains) comprise 40-50% of attapulgite, 25-30% of montmorillonite and quartz and dolomite.

The attapulgite clay in Gansu Linze and Huining places has attapulgite content of only 20-30% and low crystallization degree and order degree, and cannot be used for producing oil decolorizer, thus becoming a difficult problem which troubles the development of local attapulgite clay industry. At present, domestic large-scale colleges and universities and enterprises are in research and development, no feasible technical scheme is developed, and the attapulgite clay in Gansu is yet to be developed and utilized in large quantities.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: aiming at the defects in the background technology, the method for preparing the decoloring agent by using the low-grade attapulgite clay raw ore is provided, the process is simple, the cost is saved, and the prepared decoloring agent meets the national standard.

The scheme for solving the technical problems is as follows: a method for preparing a decoloring agent by using low-grade attapulgite clay raw ore comprises the following steps:

the method comprises the following steps: mineral separation, namely performing mineral separation treatment on low-grade attapulgite clay raw ore with the attapulgite content of 20-40% to remove gypsum and sandstone to form 100 parts of a pre-selected material H;

step two: crushing, namely crushing the pre-selected material H by using a crushing device to form crushed material K;

step three: adding acid, namely adding 20 to 45 parts of attapulgite clay solid acidifying agent into the crushed material K, and uniformly stirring to form a mixture L;

step four: grinding: the mixture L is ground to be 200 meshes in fineness, the passing rate is 80-90%, the water content is less than or equal to 10%, and the acid content is less than or equal to 0.2%, so that a finished product is prepared.

Optimally, when the content of attapulgite in the low-grade attapulgite clay raw ore in the step one is 20%, 45 parts of attapulgite clay solid acidifying agent is added in the step three.

Optimally, when the content of attapulgite in the low-grade attapulgite clay raw ore in the step one is 32%, 32 parts of attapulgite clay solid acidifying agent are added in the step three.

Optimally, when the content of attapulgite in the low-grade attapulgite clay raw ore in the step one is 40%, 20 parts of attapulgite clay solid acidifying agent is added in the step three.

Optimally, kaolinite, muscovite, dolomite, chlorite, illite and the like or montmorillonite are associated in the low-grade attapulgite clay raw ore.

In the method for preparing the decoloring agent by using the low-grade attapulgite clay raw ore, the attapulgite clay solid acidifying agent comprises the following components in percentage by weight: SiO 2₂58 to 71 percent of Al₂O₃5.0-15% of Fe₂O₃1.5-5%, 0.2-5.5% of MgO, 0.5-4.5% of CaO, 2.5-11% of free acid and the balance of inevitable impurities.

Preferably, the attapulgite clay solid acidifier comprises the following components: SiO 2₂58% of Al₂O₃Content 14.75%, Fe₂O₃4.63% of MgO, 3.17% of CaO, 2.5% of free acid and the balance unavoidable impurities.

Preferably, the attapulgite clay solid acidifier comprises the following components: SiO 2₂65% of Al₂O₃Content 12.62% Fe₂O₃2.32% of the total content, 0.45% of MgO, 1.24% of CaO, 6.28% of free acid, and the balance unavoidable impurities.

Preferably, the attapulgite clay solid acidifier comprises the following components: SiO 2₂71% of Al₂O₃6.12% of Fe₂O₃1.52 percent, 0.24 percent of MgO, 2.31 percent of CaO, 11 percent of free acid and the balance of inevitable impurities.

Preferably, the attapulgite clay solid acidifier also comprises sulfur trioxide and loss on ignition.

In the method for preparing the decoloring agent by using the low-grade attapulgite clay raw ore, the preparation method of the attapulgite clay solid acidifying agent comprises the following steps:

the method comprises the following steps: crushing, namely mixing the bentonite ore and the attapulgite clay according to the proportion of 4: 1-2: 1, and crushing to form 30 parts of crushed material A;

step two: wet purification, namely putting the crushed material A into 100 parts of water, and adding 0.5-1 part of dispersant for wet purification to form a mixture B;

step three: adding acid, and putting 3-7.5 parts of sulfuric acid with the concentration of 98% into the mixture B to be uniformly stirred to form a mixture C;

step four: heating and acidifying, namely introducing steam to heat and acidify the mixture C, wherein the reaction temperature is 120-130 ℃, the reaction pressure is 0.2-0.3 MPa, and the reaction time is 2 hours to form a mixture D;

step five: washing with acid, filter-pressing, adding water to dilute the mixture D until the content of free acid is 2.5% -11%, and then filter-pressing and dehydrating to form a mixture E;

step six: cooling and drying, namely cooling the mixture E to room temperature, and then drying or sun-drying to form a mixture F, wherein the water content of the mixture F is less than or equal to 10%;

step seven: and grinding, namely grinding the mixture E to obtain a mixture with the fineness of 200 meshes and the passing rate of more than or equal to 90 percent to form a final finished product.

Optimally, the bentonite ore in the first step is calcium bentonite, magnesium bentonite or a mixture of the calcium bentonite and the magnesium bentonite.

Preferably, the dispersant in the second step is sodium pyrophosphate, sodium hexametaphosphate or sodium silicate.

Optimally, 0.8 part of dispersing agent is added in the second step, and the dispersing agent is beneficial to improving the efficiency of wet purification.

Optimally, acid water formed after filter pressing and dehydration of the mixture D in the fifth step can be conveyed to the second step for wet purification, and the acid water can be recycled.

The invention has the beneficial effects that: 1. fills the technical blank of producing the decoloring agent from the low-grade attapulgite clay raw ore. The method can process the low-grade attapulgite clay raw ore with the attapulgite content of 20-40 percent, produce the decolorant meeting the national standard, break through the technical limitation that the decolorant can be produced only by using the high-grade attapulgite clay raw ore in the traditional process, fill the technical blank of producing the decolorant by using the low-grade attapulgite clay raw ore, provide a technical scheme for the large-scale high-valued development and utilization of the low-grade attapulgite clay raw ore, particularly attapulgite clay in Gansu areas, greatly improve the high-value utilization rate of the low-grade attapulgite clay raw ore and save mineral resources.

2. The process is simple and the cost is saved. According to the preparation method of the attapulgite clay solid acidifying agent, the production acid consumption is less, acid water formed in the acid washing and pressure filtering process can be recycled, the acid water treatment and discharge load is lower, and the enterprise pollution discharge and water and electricity utilization cost is lower. When the decoloring agent is prepared, the attapulgite clay solid acidifying agent is directly used for acidification, acid and water washing are not needed, the production process is simple, the production cost is low, and the production safety is high. Therefore, the whole process flow for producing the decolorizing agent is simple in process, high in production safety, small in acid consumption for production, low in acid water treatment and discharge load of enterprises, and good in economic and environmental benefits.

3. The product meets the national standard, and the decolorizer decolorization rate is improved. According to the attapulgite clay solid acidifier, the original special pore structure and interface properties in attapulgite clay are not damaged, acid radical ions are converted with metal ions in materials, the number of adsorbed cations is increased, the void ratio and specific surface area of the materials are improved, and the decolorization rate of the attapulgite clay decolorizer is improved. Through continuous experiments and detection, the quality indexes of the decolorant product produced by the invention are as follows: decolouring rate is greater than or equal to 70%, water content is less than or equal to 10%, free acid (by H)₂SO₄Calculated by the weight percentage of less than or equal to 0.2 percent, the fineness (passing through a 75 mu m screen) of more than or equal to 85 percent, and the bulk density of 0.5 to 1.0g/cm³Heavy metal (calculated by pb) is less than or equal to 40mg/kg, total arsenic (calculated by As) is less than or equal to 3mg/kg, and the standard of GB29225-2012 is met.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described below with reference to the following examples. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

The following three low-grade attapulgite clay raw ores are used in the following examples of the invention:

the first low-grade attapulgite clay raw ore: the main component is SiO₂47.9% of Al₂O₃Content 10.63% Fe₂O₃4.04% of MgO, 7.96% of MgO, 8.91% of CaO, SO₃The content is 2.38 percent, other impurities are 3.07 percent, and the loss on ignition is 15.11 percent. Wherein, the content of attapulgite is 20 percent, and the decolorization rate is 5.6 percent.

The second low-grade attapulgite clay raw ore: the main component is SiO₂50.4% of Al₂O₃16.55% of Fe₂O₃7.45% of MgO, 5.27% of CaO, 3.35% of SO₃The content is 2.06 percent, other impurities are 2.11 percent, and the loss on ignition is 12.81 percent. Wherein, the content of attapulgite is 32.8 percent, and the decolorization rate is 6.3 percent.

The third low-grade attapulgite clay raw ore: the main component is SiO₂57.76% Al₂O₃Content 7.46%, Fe₂O₃4.48% of MgO, 2.59% of CaO, 10.23% of SO₂The content is 1.25 percent, other impurities are 2.67 percent, and the loss on ignition is 13.56 percent. Wherein, the content of attapulgite is 40 percent, and the decolorization rate is 7.2 percent.