TW201408365A - Adsorbent for processing phosphate-containing waste water and manufacturing method thereof - Google Patents

Abstract

The invention relates to an adsorbent for processing phosphate-containing waste water and a manufacturing method thereof. The adsorbent includes a core having a magnetic carrier and a shell including oleic acid. The surface of the oleic acid-containing shell is modified with a mixture solution including allyl thiourea, and possesses the functional group of polymeric thiourea.

Description

Adsorbent for treating phosphate-containing wastewater and preparation method thereof (2)

The invention relates to an adsorbent for treating phosphate-containing wastewater and a preparation method thereof, in particular to a polymer having a polymer thiourea functional group on the surface of the adsorbent.

Sources of water pollution in recent years, such as pollutants from industrial processes such as mining, electroplating, metallurgy, and oil refining. The ions of polluted water can be divided into two major categories, heavy metal ions and amines and phosphate ions. Among them, amines and phosphate ions are the main reasons for the superior water quality.

When the phosphate-containing wastewater is treated by conventional chemical precipitation, a large amount of phosphate sludge is produced, which requires additional cost, equipment and land space for subsequent treatment of the produced sludge.

The application of magnetic carrier technology was originally developed for biochemical separation. By the mid-1970s, the development of magnetic carriers has gradually gained attention, and it is widely used in the immobilization of proteins and enzymes, drug delivery, immunoassay and biomedical sensing. The magnetic carrier technology is shown to have considerable development potential.

The object of the present invention is to provide an adsorbent for treating phosphate-containing wastewater and a preparation method thereof, and the method for synthesizing the adsorption effect of the adsorbent and the phosphate by using the magnetic carrier technology, and solving the phosphate pollution in the waste water and recycling and recycling thereof .

According to an object of the present invention, there is provided an adsorbent for treating phosphate-containing wastewater, The core of the magnetic carrier and the oleic acid shell, the surface of the oleic acid shell is modified with a modified mixture containing allyl thiourea, and has a polymer thiourea functional group.

Wherein, the magnetic carrier is magnetic particles or magnetic powder, and the core is mixed by a ratio of ferric chloride (FeCl ₃ ) and iron sulfate (FeSO ₄ ) to a molar ratio of 2:1, and precipitated triiron tetroxide ( Fe ₃ O ₄ ).

The invention further provides a preparation method for treating an adsorbent containing phosphate wastewater, which comprises the steps of: obtaining a core having a magnetic carrier, and then coating the outer surface of the core as an oleic acid coating to make the outer surface of the core body It has a layer of oleic acid shell to form a semi-finished product of adsorbent. Finally, the outer surface of the semi-finished product of the adsorbent is modified with a modified mixture containing allyl thiourea to prepare an adsorbent having a polymer thiourea functional group on the outer surface. Finished product.

Wherein, the core of the magnetic carrier and the oleic acid coating step are: firstly, ferric chloride (FeCl ₃ ) and ferric sulfate (FeSO ₄ ) having a molar ratio of 2:1 are put into 1800 ml of distilled water, mixed and stirred to form a first a mixture of liquid and a precipitate of ferroferric oxide (Fe ₃ O ₄ ), which is the core of the magnetic carrier; then the first mixture is heated to a temperature of 50 ° C, and then an appropriate amount of ammonia (NH _{3 )} OH), adjust the pH to 9.0 ± 0.1, and stir to form a second mixture; then, add 5N H ₂ SO ₄ solution to the second mixture to adjust the pH of the second mixture to the appropriate The pH value forms a third mixed liquid; 60 ml of oleic acid is added to the third mixed solution and stirred to form an oleic acid mixture; finally, the oleic acid mixture is cooled to about 30 ° C at room temperature. The outer surface of the core has a layer of oleic acid shell to form a semi-finished product of adsorbent, and the semi-finished product of the adsorbent is washed with ethanol and deionized water to a pH of 7-8, and the semi-finished product of the adsorbent is vacuum-dried.

Wherein, the surface of the adsorbent is modified with a mixture containing allyl thiourea, and the modification method comprises the steps of: preparing a mixed solution containing the modification, 400 ml of acetonitrile, 1.16 g of allylthiourea, 9.44 ml of ethylene glycol dimethacrylate (EDMA) and 1.0 g of azobisisobutyronitrile (AIBN) were stirred and mixed into a modified mixture, and about 10 g of the adsorbent semi-finished product was put into the modified mixture and nitrogen gas was introduced. The temperature is raised to 80 ° C for surface modification for 3 hours; finally, the modified semi-finished product of the adsorbent is cooled to about 30 ° C to form a finished product of the adsorbent, and the finished adsorbent is washed with ethanol and distilled water until the cleaning liquid of the adsorbent is cleaned. After the pH value is stabilized, it is vacuum dried at 70 ° C.

To facilitate understanding thereof, the preferred adsorbent for treating phosphate-containing wastewater and a method for preparing the same according to the present invention will be described below with reference to the accompanying drawings.

Accordingly, the present invention provides an adsorbent for treating phosphate-containing wastewater, see Fig. 1, comprising a magnetic carrier core 11 and an oleic acid shell 12, the surface of the oleic acid shell, containing allyl thiourea The modified mixture has a high molecular weight thiourea functional group 13 as a modification. The magnetic carrier is a magnetic particle or a magnetic powder, and the core is mixed by a ratio of ferric chloride (FeCl ₃ ) and iron sulfate (FeSO ₄ ) to a molar ratio of 2:1, and the precipitated triiron tetroxide (Fe) ₃ O ₄ ). Here, the core having the magnetic carrier is produced by mixing and precipitating the aforementioned ferric chloride (FeCl ₃ ) and iron sulfate (FeSO ₄ ), but the present invention is not limited thereto.

Please refer to FIG. 2, which is a flow chart showing a preparation method for treating an adsorbent containing phosphate wastewater, which comprises the following steps:

Step S21: Acquire a core having a magnetic carrier.

Step S22: treating the outer surface of the core with oleic acid coating, so that the outer surface of the core body has a layer of oleic acid to form a semi-finished adsorbent.

Step S23: the outer surface of the adsorbent semi-finished product, and then the modified mixture containing allyl thiourea Surface modification is carried out to prepare a finished adsorbent having a polymer thiourea functional group on the outer surface.

Please refer to FIG. 3, which is a flow chart of the core of the magnetic carrier and the manufacturing method of the oleic acid casing. The steps for making the core of the magnetic carrier and the oleic acid casing are as follows:

Step S31: adding FeCl ₃ and FeSO _{4 having a} molar ratio of 2:1 to distilled water to form a first mixed liquid, and precipitating in the first mixed liquid to produce ferroferric oxide (Fe ₃ O ₄ ), tetraoxide Triiron (Fe ₃ O ₄ ) is the aforementioned core having a magnetic carrier; wherein distilled water is 1800 ml.

Step S32: After heating the first mixed liquid to a temperature of 50 ° C, an appropriate amount of ammonia water (NH ₃ OH) is added, the pH is adjusted to 9.0 ± 0.1, and stirring is performed to form a second mixed liquid.

Step S33: A 5N H ₂ SO ₄ solution is added to the second mixture, and the pH of the second mixture is adjusted to an appropriate pH to form a third mixture.

Step S34: adding oleic acid to the third mixed solution and applying agitation to form an oleic acid mixture; wherein oleic acid is preferably 60 ml.

Step S35: The oleic acid mixture is cooled to about 30 ° C at room temperature, so that the outer surface of the core has a layer of oleic acid to form a semi-finished adsorbent.

Step S36: in ethanol, and washed with deionized water to pH adsorbent semi ^7-8.

Step S37: The semi-finished adsorbent after the cleaning process is subjected to vacuum drying treatment.

Here, the magnetic carrier and the oleic acid coating are produced by mixing and precipitating the above compounds, but the present invention is not limited thereto.

Please refer to Figure 4, which shows the modification of the adsorbent with a mixture containing allyl thiourea. Flow chart of the outer surface method. It contains the following steps:

Step S41: A mixed liquid containing the following raw materials was prepared: 400 ml of acetonitrile, 1.16 g of allylthiourea, 9.44 ml of ethylene glycol dimethacrylate (EDMA), and 1.0 g of azobisisobutyronitrile (AIBN).

Step S42: 10 g of the adsorbent semi-finished product is put into the modified mixed liquid of the step S41.

Step S43: The modified mixture containing the adsorbent semi-finished product was passed through a nitrogen gas and heated to 80 ° C for surface modification for 3 hours.

Step S44: cooling the semi-finished product of the adsorbent to about 30 ° C to form a finished adsorbent.

Step S45: washing the finished adsorbent with ethanol washing and distilled water until the pH of the washing liquid of the finished adsorbent is stable after washing.

Step S46: The finished adsorbent is vacuum dried at 70 ° C.

Here, although the surface of the magnetic carrier is modified by mixing the above compounds, the present invention is not limited thereto.

It can be seen from the above that the present invention utilizes a magnetic carrier technology and synthesizes the removal effect of the adsorbent and phosphate, and solves the problem of phosphate contamination and recycling in wastewater. In one embodiment of the present invention, the wastewater is solved in the following manner. Phosphate pollution and recycling of adsorbents: In this embodiment, phosphate water is configured using a metering bottle, distilled water and potassium dihydrogen phosphate, and according to the Environmental Protection Agency's announcement of phosphorus detection method - spectrophotometer / vitamin C method, The phosphate concentration was measured, and the reaction-related parameters were calculated. The magnetic adsorbent reaction operation parameter table is shown in Table 1.

Please refer to Figure 5, which shows the isoelectric point test. Under different pH values (4.5, 6, 7, 8, 9, 10), 1 g of magnetic polymer adsorbent is added to 100 mL of distilled water solution. At 25 ° C The temperature is oscillated for 24 hours. After the reaction, the pH value is measured. The pH value is plotted against the initial pH value to find the pH value corresponding to the origin, which is the zero point of the adsorbent.

Please refer to Figure 6 for the pH effect test. Take 1 g of magnetic polymer adsorbent and add 100 mL of phosphate solution. The concentration of phosphate is 500 mgL ^-1 at different pH values (2, 3). , 4, 5, 7, 9), shake at 24 ° C for 24 hours at constant temperature, continuously adjust the pH value during the constant temperature oscillation, after filtering the appropriate amount of solution, the Environmental Protection Agency announced the phosphorus detection method in water - spectrophotometer / The vitamin C method detects the phosphate concentration. It is known from the experimental results that the optimal pH value of the reaction is 3, which shows that the adsorbent of the present invention has an effective ability to adsorb phosphate in an acidic environment, and can be effectively applied in practical operations.

Please refer to Figure 7 for the isothermal adsorption experiment. Add 1 g of adsorbent to 100 mL of phosphate solution. The concentrations of phosphate ions are 500, 650, 800, 950, and 1100 mg L ^-1 , respectively. After adjusting the pH value of all the solutions to 3.0±0.1, shake at a constant temperature of 25 °C for 24 hours. After the reaction, filter the appropriate amount of solution, and check the phosphate concentration by the EPA's announcement of phosphorus detection method - spectrophotometer / vitamin C method. In the isothermal adsorption experiment, it can be seen from Table 2 that the phosphate concentration in the solution is adsorbed from 505 mgL ^-1 to 338 mg L ^-1 , and a large amount of phosphate in the solution is captured by the adsorbent. This experimental data can be reused by Langmuir et al. The temperature adsorption mode was simulated, and the maximum adsorption amount ( Q _m ) and the Langmuir equilibrium constant ( k _L ) were calculated to be 55.20 mgg ^-1 and 0.0013 Lmg ^{-1 , respectively} . It is shown that the adsorbent of the present invention has an excellent ability to adsorb phosphate.

According to the above, the surface of the adsorbent has a polymer thiourea functional group, and the covalently bonded amine group (-NH2) of the polymer thiourea functional group is used to make the adsorbent have good ion and phosphate ions under acidic conditions. Affinity, and has good phosphate adsorption; in addition, the adsorbent has a magnetic carrier, so the adsorbent is also magnetic, and can be quickly recovered by using an external magnetic field after use, compared with the general adsorbent. The recovery method of precipitation, filtration or centrifugation is simple and rapid.

11‧‧‧The core of the magnetic carrier

12‧‧‧oleic acid shell

13‧‧‧ polymer thiourea functional group

S21~S23‧‧‧Step process

S31~S37‧‧‧Step procedure

S41~S46‧‧‧Step procedure

Figure 1 is a schematic view of the adsorbent of the present invention.

Fig. 2 is a flow chart showing the preparation method of the adsorbent of the present invention.

Figure 3 is a flow chart showing the preparation method of the adsorbent of the present invention.

Figure 4 is a flow chart showing the preparation method of the adsorbent of the present invention.

Figure 5 shows the isoelectric point test chart.

Figure 6 is a graph showing the effect of pH on the adsorption of phosphate by magnetic polymers.

Figure 7 is a Langmuir isotherm adsorption diagram of a phosphate adsorbed by a magnetic polymeric adsorbent.

11‧‧‧The core of the magnetic carrier

12‧‧‧oleic acid shell

13‧‧‧ polymer thiourea functional group

Claims (18)

An adsorbent for treating phosphate-containing wastewater, comprising: a core having a magnetic carrier and an oleic acid shell, wherein the surface of the oleic acid shell is modified by a modified mixture containing an ethylene thiourea, and has a high Molecular thiourea functional group. The adsorbent of claim 1, wherein the magnetic carrier is a magnetic particle. The adsorbent according to claim 1, wherein the magnetic carrier is a magnetic powder. The adsorbent according to claim 2, wherein the magnetic carrier is ferroferric oxide (Fe ₃ O ₄ ). The adsorbent according to claim 4, wherein the ferric oxide (Fe ₃ O ₄ ) is mixed by a ratio of FeCl ₃ and FeSO _{4 to a} molar ratio of 2:1, and the precipitate is produced. A preparation method for treating an adsorbent containing phosphate wastewater comprises the steps of: A. obtaining a core having a magnetic carrier; B. treating the outer surface of the core with oleic acid coating to make the core body The outer surface has a layer of oleic acid shell to form a semi-finished adsorbent; C. the outer surface of the semi-finished product of the adsorbent is further modified with a mixture containing allyl thiourea to form a polymer thiourea functional group on the outer surface. The finished adsorbent. The method for producing an adsorbent according to claim 6, wherein the magnetic carrier is a magnetic particle. The method for producing an adsorbent according to claim 6, wherein the magnetic carrier is a magnetic powder. The method for preparing an adsorbent according to claim 6, wherein the magnetic carrier is ferroferric oxide (Fe ₃ O ₄ ). The method for preparing an adsorbent according to claim 9, wherein the source of ferric oxide (Fe ₃ O ₄ ) is mixed with FeCl ₃ and FeSO ₄ to form a precipitate. The method for preparing an adsorbent according to claim 10, wherein FeCl ₃ and FeSO ₄ are mixed in a ratio of 2:1. The preparation method of the adsorbent according to claim 6, wherein the steps A and B, the preparation step comprises: a. adding FeCl ₃ and FeSO _{4 having} a molar ratio of 2:1 to distilled water to form a first mixed liquid. and generating a magnetic carrier core, the lines of triiron tetroxide _{(Fe 3 O 4);.} b the mixture is heated to a first temperature reached 50 ℃, adding an appropriate amount of aqueous ammonia (NH ₃ OH), adjusted The pH is up to 9.0 ± 0.1, and a second mixture is formed by stirring; c. Subsequently, a 5N solution of H ₂ SO ₄ is added to the second mixture to adjust the pH of the second mixture to an appropriate pH. a value, forming a third mixed liquid; d. adding oleic acid to the third mixed liquid, and applying agitation to form an oleic acid mixture; e. cooling the oleic acid mixture to about 30 ° C at room temperature, so that The outer surface of the core has a layer of oleic acid shell to form a semi-finished adsorbent; f. washing the semi-finished product of the adsorbent with ethanol and deionized water to a pH of 7-8; g. the semi-finished product of the adsorbent after being cleaned Vacuum drying treatment. The method for preparing an adsorbent according to claim 12, wherein the oleic acid coating preparation method, wherein the distillation water used in the preparation step a is 1800 ml, and the amount of oleic acid is 60 ml in the preparation step d Preferably. The method for preparing an adsorbent according to claim 6, wherein the step C is The mixture of allyl thiourea is modified on the outer surface of the adsorbent, and the modification method comprises the following steps: i. preparing a modified mixture containing the following raw materials: acetonitrile, allyl thiourea, ethylene glycol dimethacrylate Ester (EDMA), azobisisobutyronitrile (AIBN); ii. The adsorbent semi-finished product is put into the modified mixture of step i; iii. The modified mixture containing the adsorbent semi-finished product is passed through nitrogen and heated to surface Modification; iv. The semi-finished product of the adsorbent is cooled to about 30 ° C to form a finished adsorbent; v. The adsorbent is washed with ethanol and distilled water until the pH of the cleaning solution of the finished adsorbent reaches Stable; vi. The finished adsorbent is vacuum dried. The method for preparing an adsorbent according to claim 14, wherein the modified mixture of the step i comprises acetonitrile-400 ml, allylthiourea-1.16 g, ethylene glycol dimethacrylate (EDMA)- 9.44 ml, and azobisisobutyronitrile (AIBN) - 1.0 g. The method for preparing an adsorbent according to claim 14, wherein the adsorbent semi-finished product of step ii is about 10 g. The method for preparing an adsorbent according to claim 14, wherein the step iii is to introduce nitrogen gas and raise the temperature to about 80 ° C, and react for about 3 hours. The method for preparing an adsorbent according to claim 14, wherein the temperature of the vacuum drying treatment of step vi is about 70 °C.