CN105502604A - Preparation of modified nano-iron and application of modified nano-iron in antibiotic drug manufacture wastewater treatment - Google Patents

Abstract

The invention discloses a method for preparing modified nano-iron and its use in antibiotic pharmaceutical waste water treatment. The modified nano-iron is prepared by using a liquid phase reduction method, and the reaction solution is in the state of microemulsion. The steps are as follows: under nitrogen conditions, add a surface modifier to the ethanol aqueous solution of the ferrous salt, stir and mix; add the prepared borohydride alkali aqueous solution dropwise into the ethanol aqueous solution of the ferrous salt, and after the addition is completed, , and continue to react for 20-30 minutes to form a black precipitate; the black precipitate is filtered, washed, centrifuged, separated, and dried to obtain modified nano-iron. The preparation cost of the present invention is low, which is lower than that of commercial nano-iron, and the operation process is simple; the prepared modified nano-iron has large specific surface area, uniform particle size, good dispersibility and high reduction activity; it can be used in the treatment of antibiotic pharmaceutical wastewater, which can be fast and efficient degrade pollution.

Description

Preparation of modified nano-iron and its application in antibiotic pharmaceutical wastewater treatment

technical field

The invention belongs to the technical field of wastewater treatment, and relates to a preparation method of modified nano-iron and its application in treating antibiotic pharmaceutical wastewater.

Background technique

With the rapid development of my country's pharmaceutical industry, antibiotics are currently one of the most widely used drugs, and the wastewater produced in the production process has the characteristics of high COD concentration, large chroma, high sulfate concentration, and difficult biodegradation. , many of which are refractory organics such as residual antibiotics have inhibitory effect on microorganisms.

Most of the common traditional wastewater treatment processes are not efficient in removing antibiotics, and it is difficult to achieve the expected effect. At present, most traditional activated sludge sewage treatment plants mainly remove antibiotics through sludge adsorption, but only part of the antibiotics are degraded, and the sludge with adsorbed antibiotics will bring antibiotics into the soil through fertilization, which will infiltrate into groundwater, or Entering the surface water will not only cause greater harm to the ecological environment, but the antibiotics have not been fundamentally eliminated.

Chemical methods can oxidize organic pollutants, especially refractory organic pollutants, into inorganic substances, completely destroying organic substances, so as to meet the requirements of harmless treatment. However, the general chemical method is difficult to be widely used because of the high cost. Therefore, finding low-cost and high-efficiency chemical treatment methods is the key to solving this problem.

In addition to the characteristics of zero-valent iron, nano-zero-valent iron also has the characteristics of nano-materials such as small size, large specific surface area, and higher reduction activity than ordinary zero-valent iron. It has become a water treatment with broad application prospects. Material. However, the purchased nano-zero-valent iron is expensive, and the price is about 100 times that of self-made nano-iron, which cannot solve the problem of high cost in chemical methods, and the active components of commercial nano-iron are limited. Therefore, the prepared nano-iron can not only effectively improve the degradation rate of antibiotics, but also can effectively solve the problem of high processing cost due to the low cost of raw materials and simple preparation process.

In addition, due to the magnetic attraction and intermolecular force between the nano-iron particles, it is easy to agglomerate. Therefore, it is also necessary to improve in this respect to prevent agglomeration.

Contents of the invention

The technical problem to be solved by the present invention is to overcome the deficiencies in the prior art and provide a method for preparing modified nano-iron with simple preparation process, low cost, large specific surface area, high reduction activity, uniform particle size and good dispersibility .

The invention also provides a method for rapidly and efficiently degrading antibiotic pharmaceutical wastewater.

A method for preparing modified nano-iron provided by the invention is characterized in that it comprises the following steps:

(1) Under the protection of nitrogen, add a surface modifier to the ethanol aqueous solution of ferrous salt (ethanol: water = 3:7-1:9), stir electrically for 15-20min, and mix well; The aqueous alkali solution was added dropwise to the above mixed solution, and after the dropwise addition was completed, the reaction was continued for 20-30 minutes at a temperature of 15°C-35°C to obtain a black solid precipitate;

(2) Filter the obtained black precipitate in a 0.22 μm filter membrane, wash with deionized water and ethanol 2-3 times, centrifuge (1500-3500r/min) for 10-15min, and use a magnetic material to separate . The separated black solid is precipitated at a temperature of 20°C-60°C and vacuum-dried for 12h-48h to obtain the modified nano-iron.

1. The preparation method of modified nano-iron as claimed in claim 1, characterized in that, preferably, the ferrous salt is ferrous sulfate, ferrous nitrate or ferrous chloride. The surface modifier is CTAB+polyethylene glycol or SDS+polyethylene glycol. The borohydride is sodium borohydride or potassium borohydride.

2. the preparation method of modified nanometer iron as claimed in claim 1 is characterized in that, preferably, the ratio of the amount of substance of described ferrous salt and borohydride is 1: 1-1: 3; The concentration of modifier is 0.005-0.03mol/L.

3. The method for preparing modified nano-iron according to claim 1, characterized in that, preferably, the particle size range of the modified nano-iron is 20-80nm.

4. the application of the modified nano-iron prepared as claimed in claim 1-4 in antibiotic pharmaceutical wastewater, is characterized in that, preferably, the antibiotic that described pharmaceutical wastewater contains is sulfamethoxazole, amoxicillin, norfloxacin sand star.

5. The application of the modified nano-iron prepared according to claim 1-5 in antibiotic pharmaceutical wastewater, characterized in that, preferably, the reaction time for treating wastewater is 0.1-4h, and the reaction temperature is 15°C-35°C, The final concentration of the modified nanometer iron is 1.0-36mmol/L.

Beneficial effects of the present invention:

The raw material of the modified nano-iron paper cup used in the present invention is cheap and easy to obtain, and the operation process is simple; the prepared modified nano-iron has a large specific surface area, uniform particle size, good dispersibility and high reduction activity; in the treatment of antibiotic pharmaceutical wastewater, it can It can quickly and efficiently degrade organic pollutants, has low energy consumption and low pollution, and has certain application prospects in the treatment of antibiotic pharmaceutical wastewater.

Description of drawings

FIG. 1 is a TEM image of the modified nano-iron prepared in Example 1.

Fig. 2 is the effect diagram of the treatment effect of removing antibiotic pharmaceutical wastewater by iron powder from different sources in Example 3.

detailed description

The present invention will be described in further detail below in conjunction with specific embodiments. The methods are conventional methods unless otherwise specified. The raw materials can be obtained from open commercial channels unless otherwise specified.

Example 1

The preparation of modified nano-iron and its application in the treatment of antibiotic pharmaceutical wastewater include the following steps: under the protection of nitrogen, adding ferrous salt to ethanol aqueous solution (ethanol: water = 3:7-1:9) for surface modification Add the aqueous solution of alkali containing borohydride to the above mixture drop by drop. After the dropwise addition, continue the reaction at 15°C-35°C for 20-30min to obtain a black solid precipitation;

(2) Filter the obtained black precipitate in a 0.22 μm filter membrane, wash with deionized water and ethanol 2-3 times, centrifuge (1500-3500r/min) for 10-15min, and use a magnetic material to separate . The separated black solid is precipitated at a temperature of 20°C-60°C and vacuum-dried for 12h-48h to obtain the modified nano-iron.

Example 2

The modified nano-iron in Example 1 was used for the treatment of sulfamethoxazole pharmaceutical wastewater.

The modified nano-iron in Example 1 was used for the treatment of amoxicillin pharmaceutical wastewater.

The modified nano-iron in Example 1 was used for norfloxacin pharmaceutical wastewater treatment.

The present invention selects sulfamethoxazole, amoxicillin, norfloxacin polluted wastewater as pharmaceutical wastewater evaluation index, because antibiotic wastewater such as these three kinds of drugs sulfamethoxazole, amoxicillin, norfloxacin contains a large amount of refractory organic matter , the residues in the water have a strong inhibitory effect on organisms, and if they exist in the water environment for a long time, they will pose a huge threat to the ecological environment. How to quickly and effectively degrade antibiotic drugs in wastewater is of great significance to the treatment of pharmaceutical wastewater.

Example 3

Modified nano-iron is used in the treatment of antibiotic pharmaceutical wastewater, and the reduction activity evaluation test is used, as shown in the following steps:

(1) Composition of simulated antibiotic pharmaceutical wastewater: Wastewater: 100ml; sulfamethoxazole concentration 10mg/L.

Activity evaluation method: In the above-mentioned simulated sulfamethoxazole pharmaceutical wastewater, add 0.08g of modified nano-iron prepared in Example 1, after reacting for 1.0h, use a centrifuge to centrifuge the solution after reaction at a speed of 3000r/min for 10min, and After vacuum ultrafiltration with a 0.22 μm organic filter membrane, the filtrate was collected for testing.

(2) Composition of simulated antibiotic pharmaceutical wastewater: Wastewater: 100ml; the concentration of amoxicillin is 10mg/L.

Activity evaluation method: Add 0.14 g of modified nano-iron in Example 1 to the above-mentioned simulated amoxicillin drug wastewater. After reacting for 3.5 hours, use a centrifuge to centrifuge the reacted solution at a speed of 3000 r/min for 10 min. After vacuum ultrafiltration of the filter membrane, the filtrate was collected for testing.

(3) Composition of simulated antibiotic pharmaceutical wastewater: Wastewater: 100ml; containing norfloxacin concentration 10mg/L.

Activity evaluation method: In the above-mentioned simulated norfloxacin pharmaceutical wastewater, add 0.1 g of modified nano-iron in Example 1, and react for 3.0 h, use a centrifuge to centrifuge the reacted solution at a speed of 3000 r/min for 10 min, and pass through a 0.22 μm After vacuum ultrafiltration with an organic filter membrane, the filtrate was collected for testing.

Use high-performance liquid chromatography (HPLC) to draw the standard concentration curves of three kinds of drugs respectively, and then calculate the drug removal rate by measuring the liquid to be tested.

Comparative example 1

Commercial iron powder used to treat sulfamethoxazole pharmaceutical wastewater. The specific operation method is carried out according to the above-mentioned reducing activity evaluation test.

Comparative example 2

Commercial iron powder used to treat amoxicillin pharmaceutical wastewater. The specific operation method is carried out according to the above-mentioned reducing activity evaluation test.

Comparative example 3

Commercial iron powder used to treat norfloxacin pharmaceutical wastewater. The specific operation method is carried out according to the above-mentioned reducing activity evaluation test.

The commercial iron powder used in the comparative example was purchased from Tianjin Jinke Fine Chemical Research Institute.

The reduction activity evaluation results of the modified nano-iron and commercial iron powder obtained in this example are shown in FIG. 2 .

The modified nano-iron in the present invention is applied after the treatment of antibiotic pharmaceutical wastewater. The removal rates of sulfamethoxazole, amoxicillin and norfloxacin reached 99.52%, 83.94% and 90.60%, respectively.

The modified nano-iron prepared by the present invention has a simple preparation process, short preparation period, simple operation, and low-cost raw materials. It has the characteristics of uniformity, good dispersion, high reactivity and high repair efficiency, and can quickly and efficiently degrade organic pollutants.

The above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person familiar with the art can use the above disclosure without departing from the technical solution of the present invention. Equivalent changes or modifications are made to the technical solutions of the present invention, or modifications are made to equivalent embodiments of equivalent changes. Therefore, all equivalent changes or modifications made according to the technical solutions of the present invention shall fall within the protection scope of the present invention.

Claims (6)

1. a preparation method for modified Nano iron, is characterized in that, comprises the following steps:

(1) under nitrogen protection, by aqueous ethanolic solution (ethanol: water=3: add surface-modifying agent 7-1: 9), electric stirring 15-20min, the mixing mixing of ferrous salt; Alkali aqueous solution containing hydroborate is dropwise added above-mentioned mixed solution, after dropwising, at 15 DEG C of-35 DEG C of temperature, continues reaction 20-30min, obtain black solid precipitation;

(2) black precipitate of acquisition is filtered in 0.22 μm of filtering membrane, respectively wash 2-3 time with deionized water and ethanol, whizzer (rotating speed is 1500-3500r/min) centrifugal 10-15min, use magneticsubstance to be separated.Under separating obtained black solid is deposited in 20 DEG C of-60 DEG C of temperature, vacuum-drying 12h-48h, obtains modified Nano iron.

2. the preparation method of modified Nano iron as claimed in claim 1, is characterized in that, in described step (1), ferrous salt is ferrous sulfate, Iron nitrate or iron protochloride.Described surface-modifying agent is CTAB+ polyoxyethylene glycol or SDS+ polyoxyethylene glycol.Described hydroborate is sodium borohydride or POTASSIUM BOROHYDRIDE.

3. the preparation method of modified Nano iron as claimed in claim 1, it is characterized in that, described ferrous salt is 1: 1-1: 3 with the ratio of the amount of substance of hydroborate; The concentration of described surface-modifying agent is 0.005-0.03mol/L.

4. the preparation method of modified Nano iron as claimed in claim 1, it is characterized in that, the particle size range of described modified Nano iron is at 20-80nm.

5. the application of modified Nano iron in antibiotic pharmaceutical wastewater prepared as described in claim 1-4, is characterized in that, the microbiotic that described pharmacy waste water contains is one or more in sulfamethoxazole, amoxycilline Trihydrate bp, norfloxicin.

6. the application of modified Nano iron in antibiotic pharmaceutical wastewater prepared as described in claim 1-5, it is characterized in that, the reaction times is 0.1-4h, temperature of reaction is 15 DEG C-35 DEG C, and the final concentration of described modified Nano iron is 1.0-36mmol/L.