阅读说明：本技术 一种用丙炔噁草酮副产物制备絮凝剂的方法 (Method for preparing flocculant by using oxadiargyl byproduct ) 是由 王龙 张海松 郭超 王林 梁院龙 赵乐 于 2020-07-08 设计创作，主要内容包括：本申请提供的一种用丙炔噁草酮副产物制备絮凝剂的方法,包括如下步骤：检测以及调节聚合氯化铝溶液酸度,使所述聚合氯化铝溶液酸度在15-20％；向所述聚合氯化铝溶液中加入铝酸钙和硫代硫酸钠,得到反应液；将所述反应液在80-100℃反应3-5h以及冷却至室温得到絮凝剂原液；检测以及调节所述絮凝剂原液的酸度,使所述絮凝剂原液酸度在10-13％,得到絮凝剂。本申请提供的一种用丙炔噁草酮副产物制备絮凝剂的方法在现有工艺的基础上,对生产中产生的聚合氯化铝进行进一步的处理,使聚合氯化铝的含量≥10％,达到国家聚合氯化铝的合格标准,从而实现了对丙炔噁草酮工艺的副产物回收再利用,提高效率,节能减排。(The application provides a method for preparing a flocculant by using oxadiargyl by-products, which comprises the following steps: detecting and adjusting the acidity of the polyaluminium chloride solution to enable the acidity of the polyaluminium chloride solution to be 15-20%; adding calcium aluminate and sodium thiosulfate into the polyaluminium chloride solution to obtain a reaction solution; reacting the reaction solution at 80-100 ℃ for 3-5h, and cooling to room temperature to obtain a flocculant stock solution; and detecting and adjusting the acidity of the flocculant stock solution to enable the acidity of the flocculant stock solution to be 10-13% to obtain the flocculant. The method for preparing the flocculant by using the oxadiargyl by-product is based on the prior art, and is used for further treating the polyaluminium chloride generated in the production, so that the content of the polyaluminium chloride is more than or equal to 10 percent and reaches the national standard of the qualification of the polyaluminium chloride, thereby realizing the recycling of the by-product of the oxadiargyl process, improving the efficiency, saving energy and reducing emission.)

1. A method for preparing a flocculant by using oxadiargyl by-product is characterized by comprising the following steps:

detecting and adjusting the acidity of the polyaluminium chloride solution to enable the acidity of the polyaluminium chloride solution to be 15-20%;

adding calcium aluminate and sodium thiosulfate into the polyaluminium chloride solution to obtain a reaction solution;

reacting the reaction solution at 80-100 ℃ for 3-5h, and cooling to room temperature to obtain a flocculant stock solution;

and detecting and adjusting the acidity of the flocculant stock solution to enable the acidity of the flocculant stock solution to be 10-13% to obtain the flocculant.

2. The method for preparing the flocculant by using the oxadiargyl by-product as the claim 1, wherein the acidity of the polyaluminum chloride solution is detected and adjusted to be 15-20%, the acidity of the polyaluminum chloride solution is adjusted by using caustic soda flakes or hydrogen chloride gas, and the acidity of the polyaluminum chloride solution is higher than 15-20% and is adjusted by using caustic soda flakes; and regulating the acidity of the polyaluminium chloride solution by using hydrogen chloride gas when the acidity is lower than 15-20%.

3. The method for preparing the flocculant by using the oxadiargyl by-product according to claim 1, wherein in the step of adding calcium aluminate and sodium thiosulfate into the polyaluminum chloride solution to obtain the reaction solution, the mass ratio of the polyaluminum chloride solution to the added calcium aluminate and sodium thiosulfate is 75 (8-12): 2.

4. The method for preparing the flocculant by using the oxadiargyl by-product as claimed in claim 1, wherein in the step of reacting the reaction solution at 80-100 ℃ for 3-5h and cooling to room temperature to obtain the flocculant stock solution, the obtained flocculant stock solution is allowed to stand at room temperature for 24-36 h.

5. The method for preparing the flocculant by using the oxadiargyl by-product as claimed in claim 1, wherein the step of detecting and adjusting the acidity of the flocculant stock solution to make the acidity of the flocculant stock solution be 10-13%, and the step of adjusting the acidity of the flocculant stock solution in the step of obtaining the flocculant, is performed by using caustic soda flakes.

6. The method for preparing the flocculant by using the oxadiargyl by-product according to claim 1, wherein the mass fraction of alumina in the obtained flocculant is more than or equal to 10%.

Technical Field

The application relates to the technical field of flocculating agents, in particular to a method for preparing a flocculating agent by using oxadiargyl byproducts.

Background

The first method is to adopt 2, 4-dichlorophenol as an initial raw material and carry out the steps of nitration, etherification, reduction, diazotization, acidification, cyclization and the like; secondly, 2, 4-dichlorophenol is used as an initial raw material, an intermediate substituted aniline is prepared through etherification, nitration and reduction, phthalylation is carried out, and finally, the target compound is obtained through cyclization with phosgene; the third is 2, 4-dichloronitrobenzene, 5-tert-butyl-1, 3, 4-oxadiazole-2 (3H) -ketone as the starting material, and the target product is obtained through coupling, reduction and rearrangement reaction and final etherification with propargyl chloride.

In the process of preparing oxadiargyl, byproduct polyaluminium chloride is generated, the polyaluminium chloride can be sold and used as a flocculating agent, but the content of the aluminum chloride generated in the process is between 5 and 6 percent and does not meet the national standard. Many plants require specialized companies to handle this portion of the by-product, increasing production costs. So the polyaluminium chloride which is the byproduct of oxadiargyl is difficult to recycle at present.

Disclosure of Invention

The application provides a method for preparing a flocculant by using an oxadiargyl byproduct, which aims to solve the problem that polyaluminium chloride as the oxadiargyl byproduct is difficult to recycle.

The application provides a method for preparing a flocculant by using oxadiargyl byproducts, which comprises the following steps:

detecting and adjusting the acidity of the polyaluminium chloride solution to enable the acidity of the polyaluminium chloride solution to be 15-20%;

adding calcium aluminate and sodium thiosulfate into the polyaluminium chloride solution to obtain a reaction solution;

reacting the reaction solution at 80-100 ℃ for 3-5h, and cooling to room temperature to obtain a flocculant stock solution;

and detecting and adjusting the acidity of the flocculant stock solution to enable the acidity of the flocculant stock solution to be 10-13% to obtain the flocculant.

Optionally, the acidity of the polyaluminium chloride solution is detected and adjusted, so that the acidity of the polyaluminium chloride solution is adjusted in a step of 15-20%, the acidity of the polyaluminium chloride solution is adjusted by using caustic soda flakes or hydrogen chloride gas, and the acidity of the polyaluminium chloride solution is higher than 15-20% and is adjusted by using caustic soda flakes; and regulating the acidity of the polyaluminium chloride solution by using hydrogen chloride gas when the acidity is lower than 15-20%.

Optionally, in the step of adding calcium aluminate and sodium thiosulfate into the polyaluminium chloride solution to obtain the reaction solution, the mass ratio of the polyaluminium chloride solution to the added calcium aluminate and sodium thiosulfate is 75 (8-12): 2.

Optionally, in the step of reacting the reaction solution at 80-100 ℃ for 3-5h and cooling to room temperature to obtain the flocculant stock solution, standing the obtained flocculant stock solution at room temperature for 24-36 h.

Optionally, the acidity of the flocculant stock solution is detected and adjusted to be 10-13%, and in the step of obtaining the flocculant, the acidity of the flocculant stock solution is adjusted by using caustic soda flakes.

Optionally, the mass fraction of the alumina in the obtained flocculant is more than or equal to 10%.

According to the technical scheme, the method for preparing the flocculant by using the oxadiargyl byproduct provided by the application comprises the following steps: the application provides a method for preparing a flocculant by using oxadiargyl by-products, which comprises the following steps: detecting and adjusting the acidity of the polyaluminium chloride solution to enable the acidity of the polyaluminium chloride solution to be 15-20%; adding calcium aluminate and sodium thiosulfate into the polyaluminium chloride solution to obtain a reaction solution; reacting the reaction solution at 80-100 ℃ for 3-5h, and cooling to room temperature to obtain a flocculant stock solution; and detecting and adjusting the acidity of the flocculant stock solution to enable the acidity of the flocculant stock solution to be 10-13% to obtain the flocculant. The method for preparing the flocculant by using the oxadiargyl by-product is based on the prior art, and is used for further treating the polyaluminium chloride generated in the production, so that the content of the polyaluminium chloride is more than or equal to 10 percent and reaches the national standard of the qualified polyaluminium chloride, thereby realizing the recycling of the by-product of the oxadiargyl process, improving the efficiency, saving energy and reducing emission.

Drawings

In order to more clearly explain the technical solution of the present application, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious to those skilled in the art that other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a schematic flow chart of a process for preparing a flocculant from oxadiargyl by-product according to an embodiment of the present application.

Detailed Description

Reference will now be made in detail to embodiments, examples of which are illustrated in the accompanying drawings. When the following description refers to the accompanying drawings, like numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following examples do not represent all embodiments consistent with the present application. But merely as exemplifications of systems and methods consistent with certain aspects of the application, as recited in the claims.

The process flow for preparing oxadiargyl comprises the following steps: esterification, etherification, diazotization, cyclization, hydrolysis and synthesis. During the diazotization process, a centrifugal mother liquor is used for removing a reducing agent stannous chloride and recovering the working section. The recovery of the reducing agent stannous chloride is to recover elemental tin which is generated by reduction reaction of stannic chloride which is generated by reaction and incompletely reacted stannous chloride in the original system. In the process, aluminum powder is used as a reducing agent for reducing tin ions, and finally tin simple substances are recovered through suction filtration, so that mother liquor becomes a byproduct flocculant, but in the production process, the content of effective component alumina in the byproduct flocculant cannot reach the product index of the national standard due to the influence of material proportion and related factors, so that the flocculant needs to be further processed to reach the national standard, the byproduct flocculant can be sold, the flocculant is distilled and concentrated to reach the standard, and the production cost is higher than the sales profit.

The application provides a method for preparing a flocculant by using oxadiargyl byproducts, which comprises the following steps:

s1: detecting and adjusting the acidity of the polyaluminium chloride solution to enable the acidity of the polyaluminium chloride solution to be 15-20%;

performing acidity test on a polyaluminium chloride solution, namely initial mother liquor, and performing acidity adjustment on the mother liquor by using caustic soda flakes or hydrogen chloride gas to control the acidity of the mother liquor to be 15-20%;

wherein the acidity of the polyaluminium chloride solution is higher than 15-20% and the acidity is adjusted by using caustic soda flakes; and regulating the acidity of the polyaluminium chloride solution by using hydrogen chloride gas when the acidity is lower than 15-20%.

In practical application, since the addition of alkaline solution or acidic solution can affect the purity and basicity of the solution and bring in additional impurities, when the polyaluminium chloride solution is adjusted, alkaline solid flake alkali or hydrogen chloride gas is adopted, so that the damage to the basicity of the solution and the influence on the purity of the solution can be avoided.

S2: adding calcium aluminate and sodium thiosulfate into the polyaluminium chloride solution to obtain a reaction solution;

and adding calcium aluminate and sodium thiosulfate into the polyaluminium chloride solution, wherein the mass ratio of the polyaluminium chloride solution to the added calcium aluminate and sodium thiosulfate is 75 (8-12) to 2, and the step is carried out at normal temperature.

In practical applications, sodium thiosulfate is used as an antioxidant to prevent oxidation due to elevated temperatures in the subsequent step.

S3: reacting the reaction solution at 80-100 ℃ for 3-5h, and cooling to room temperature to obtain a flocculant stock solution;

reacting the polyaluminium chloride solution added with calcium aluminate and sodium thiosulfate at 80-100 ℃ for 3-5h, cooling to room temperature to obtain a flocculant stock solution, and standing the flocculant stock solution at room temperature for 24-36 h.

The reaction equation for the participation of calcium aluminate during the high temperature reaction is shown below:

CaO^.Al₂O₃+3HCl＝Al₂(OH)_nCl_6-n+CaCl₂+2H₂O；

the reaction is carried out to a certain degree, and when the pH value is proper, two adjacent hydroxyl groups of the aluminum chloride generate bridging action to polymerize and self-polymerize, and are finally converted into polyaluminium chloride, and the specific reaction is as follows:

mAl₂(OH)_nCl_6-n＝[Al₂(OH)_nCl_6-n]_m；

in practical application, the flocculant stock solution obtained is kept stand at room temperature for 24-36h because precipitation is generated in the step, the obtained stock solution is difficult to filter, and the flocculant stock solution obtained is kept stand at room temperature for 24-36h in order to settle the precipitation.

S4: and detecting and adjusting the acidity of the flocculant stock solution to enable the acidity of the flocculant stock solution to be 10-13% to obtain the flocculant.

In practical application, the flocculant stock solution obtained in the previous step S3 needs to be filtered, the acidity of the flocculant stock solution after filtering is detected after impurities are removed, and the acidity of the flocculant stock solution is adjusted by using caustic soda flakes, so that the acidity of the flocculant stock solution is controlled to be 10-13%, and finally the flocculant is obtained. The mass fraction of the alumina in the flocculant is improved from 5-6% to 10-15% by the method for preparing the flocculant. Fig. 1 is a schematic flow chart of a process for preparing a flocculant from oxadiargyl by-product according to an embodiment of the present application.

Wherein the content of alumina in the flocculant is analyzed and calculated by the following steps:

weighing 13g of the flocculant liquid sample, dissolving the flocculant liquid sample with ultrapure water to obtain a solution, transferring the solution into a 250mL volumetric flask, diluting to a scale, and shaking up. Dry-filter with medium speed filter paper and label the solution as test solution a.

Weighing 10mL of test solution A, placing the test solution A in a 250mL conical flask, adding 10mL of nitric acid solution, boiling for 1min, cooling to room temperature, adding 20mL of ethylene diamine tetraacetic acid disodium solution, dropwise adding 3 drops of thymol blue indicator solution, neutralizing with ammonia water solution until the test solution turns from red to yellow, and boiling for 2 min. After cooling, 10mL of acetic acid-sodium acetate buffer solution and two drops of xylenol orange indicator solution are added, 50mL of water is added, zinc chloride standard titration solution is used for titration until the solution changes from light yellow to reddish, namely, a midpoint, and meanwhile, a blank experiment is carried out.

The content of alumina is in mass fraction omega₁In% by weight, the value is calculated as follows:

V₀the value of the volume of the standard titration solution of zinc chloride consumed for the blank test, V the value of the volume of the standard titration solution of zinc chloride consumed for the test sample, c the value of the actual concentration of the standard titration solution of zinc chloride, M the molar mass of aluminum chloride, M the mass of the test sample, V₁Value of volume of the sample solution A, V_AIs a value of the total volume of the sample solution A.

The following is a first embodiment provided by the present application:

300mL of polyaluminum chloride solution with an alumina content of 5.88% was placed in a beaker. The polyaluminum chloride solution was subjected to an acidity test, and the acidity of the solution was adjusted to 20% using caustic soda flakes.

The above polyaluminum chloride solution was transferred to a four-necked flask, 43g of calcium aluminate and 10g of sodium thiosulfate were added to the solution at normal temperature, and a thermometer, a condenser and a stirrer were provided to the four-necked flask. The electric stirrer was turned on and the solution was stirred until the solid was completely dissolved. The stirring device used therein is a tetrafluoro stir bar because of its acid and alkali resistance.

And (3) moving the four-mouth flask into an electric heating jacket for heating, stirring and heating at the moment, stopping heating when the temperature reaches 80 ℃, performing condensation reflux by using a condensing tube, reacting for 2 hours, heating to 90 ℃, reacting for 2 hours, finishing the reaction, and cooling the obtained flocculant stock solution to room temperature.

And standing the flocculant stock solution at room temperature for 36 hours, performing suction filtration on the flocculant stock solution by using a vacuum pump, removing impurities to obtain a solution, namely the flocculant stock solution, performing acidity test on the flocculant stock solution, adding 15g of flake caustic soda to control the acidity of the flocculant stock solution to be 10%, and finally obtaining the flocculant. Wherein the content of the aluminum oxide in the flocculant is 10.25 percent. The mass fraction of water insoluble substances in the flocculant is less than or equal to 0.4 percent, the mass fraction of Fe is less than or equal to 3.5 percent, the mass fraction of As is less than or equal to 0.0005 percent, the mass fraction of Pb is less than or equal to 0.002 percent, the mass fraction of Cd is less than or equal to 0.01 percent, the mass fraction of Hg is less than or equal to 0.00005 percent, and the mass fraction of Cr is less than or equal to 0.05.

The following is a second example provided by the present application:

300ml of polyaluminium chloride solution is taken in a beaker, wherein the content of alumina in the polyaluminium chloride solution is 5.76 percent. The polyaluminum chloride solution was subjected to an acidity test, and the acidity of the solution was adjusted to 15% using caustic soda flakes.

The above polyaluminum chloride solution was transferred to a four-necked flask, 40g of calcium aluminate and 10g of sodium thiosulfate were added to the solution at normal temperature, and a thermometer, a condenser and a stirrer were provided to the four-necked flask. The electric stirrer was turned on and the solution was stirred until the solid was completely dissolved. The stirring device used therein is a tetrafluoro stir bar because of its acid and alkali resistance.

And (3) moving the four-mouth flask into an electric heating jacket for heating, stirring and heating at the moment, stopping heating when the temperature reaches 90 ℃, performing condensation reflux by using a condensing tube, reacting for 2 hours, heating to 100 ℃, reacting for 1 hour, and finishing the reaction to obtain a flocculant stock solution and cooling to room temperature.

And standing the flocculant stock solution at room temperature for 24 hours, performing suction filtration on the flocculant stock solution by using a vacuum pump, removing impurities to obtain a solution, namely the flocculant stock solution, performing acidity test on the flocculant stock solution, adding 13g of flake caustic soda to control the acidity of the flocculant stock solution to be 13%, and finally obtaining the flocculant. Wherein the content of the aluminum oxide in the flocculant is 10.13 percent. The mass fraction of water insoluble substances in the flocculant is less than or equal to 0.4%, the mass fraction of Fe is less than or equal to 3.5%, the mass fraction of As is less than or equal to 0.0005%, the mass fraction of Pb is less than or equal to 0.002%, the mass fraction of Cd is less than or equal to 0.01%, the mass fraction of Hg is less than or equal to 0.00005%, and the mass fraction of Cr is less than or equal to 0.05%.

The following is a third embodiment provided by the present application:

300ml of polyaluminium chloride solution is taken in a beaker, wherein the content of alumina in the polyaluminium chloride solution is 5.52 percent. The polyaluminum chloride solution was subjected to an acidity test, and the acidity of the solution was adjusted to 18% using caustic soda flakes.

The above polyaluminum chloride solution was transferred to a four-necked flask, 40g of calcium aluminate and 10g of sodium thiosulfate were added to the solution at normal temperature, and a thermometer, a condenser and a stirrer were provided to the four-necked flask. The electric stirrer was turned on and the solution was stirred until the solid was completely dissolved. The stirring device used therein is a tetrafluoro stir bar because of its acid and alkali resistance.

And (3) moving the four-mouth flask into an electric heating jacket for heating, stirring and heating at the moment, stopping heating when the temperature reaches 90 ℃, performing condensation reflux by using a condensing tube, reacting for 2 hours, heating to 100 ℃, reacting for 3 hours, and finishing the reaction to obtain a flocculant stock solution and cooling to room temperature.

And standing the flocculant stock solution at room temperature for 36 hours, performing suction filtration on the flocculant stock solution by using a vacuum pump, removing impurities to obtain a solution, namely the flocculant stock solution, performing acidity test on the flocculant stock solution, adding 13.5g of flake caustic soda to control the acidity of the flocculant stock solution to be 11%, and finally obtaining the flocculant. Wherein the content of alumina in the flocculant is 11%. The mass fraction of water insoluble substances in the flocculant is less than or equal to 0.4 percent, the mass fraction of Fe is less than or equal to 3.5 percent, the mass fraction of As is less than or equal to 0.0005 percent, the mass fraction of Pb is less than or equal to 0.002 percent, the mass fraction of Cd is less than or equal to 0.01 percent, the mass fraction of Hg is less than or equal to 0.00005 percent, and the mass fraction of Cr is less than or equal to 0.05.

According to the technical scheme, the method for preparing the flocculant by using the oxadiargyl byproduct provided by the application comprises the following steps: the application provides a method for preparing a flocculant by using oxadiargyl by-products, which comprises the following steps: detecting and adjusting the acidity of the polyaluminium chloride solution to enable the acidity of the polyaluminium chloride solution to be 15-20%; adding calcium aluminate and sodium thiosulfate into the polyaluminium chloride solution to obtain a reaction solution; reacting the reaction liquid at 80-100 ℃ for 3-5h, and cooling to room temperature to obtain a flocculant stock solution; and detecting and adjusting the acidity of the flocculant stock solution to enable the acidity of the flocculant stock solution to be 10-13% to obtain the flocculant. The method for preparing the flocculant by using the oxadiargyl by-product is based on the prior art, and is used for further treating the polyaluminium chloride generated in the production, so that the content of the polyaluminium chloride is more than or equal to 10 percent and reaches the national standard of the qualification of the polyaluminium chloride, thereby realizing the recycling of the by-product of the oxadiargyl process, improving the efficiency, saving energy and reducing emission.