CN102698763A - Preparation of steel-slag-based inorganic polymer-zinc oxide semiconductor composite catalyst and application of steel-slag-based inorganic polymer-zinc oxide semiconductor composite catalyst in degradation of dyeing wastewater - Google Patents

Abstract

The invention discloses a preparation of a steel-slag-based inorganic polymer-zinc oxide semiconductor composite catalyst and the application of the steel-slag-based inorganic polymer-zinc oxide semiconductor composite catalyst in the degradation of dyeing wastewater. The preparation method relates to the synthesis of an inorganic polymer and the loading of a zinc oxide semiconductor and comprises the following steps: synthesizing a steel-slag-based inorganic polymer cementing material from an industrial solid waste steel slag under the excitation of sodium silicate, immersing the inorganic polymer cementing material into zinc nitrate aqueous solution, and baking the mixture to form the steel-slag-based inorganic polymer-zinc oxide semiconductor composite catalyst. The semiconductor composite catalyst is applied to the degradation reactions of congo red dye and methylene blue dye under ultraviolet light; and the highest degradation rates of both of the two dyes reach 100 percent to achieve high degradation rate and no secondary pollution. The preparation process of the semiconductor composite catalyst is simple and can implement a large-scale preparation and application.

Description

Slag based inorganic polymer-preparation of zinc oxide semi-conductor composite catalyst and the application in degradation of dye waste water thereof

Technical field

The invention belongs to the preparation of inorganic semiconductor composite catalyst and the application in field of waste water treatment thereof, be specifically related to a kind of slag based inorganic polymer-preparation of zinc oxide semi-conductor composite catalyst and application in degradation of dye waste water thereof.

Background technology

China is a big steel country, and China's crude steel output was 6.2665 hundred million tons in 2010, accounted for 44.3% of world's output of steel ^[1], 1 ton of crude steel of every production will produce the slag of 15%-20%, and only the slag of China's discharging in 2010 surpasses 100,000,000 tons, and is current, and the slag total amount that domestic steel mill is piled up surpasses 200,000,000 tons, takes up an area of more than 10,000 mu, and annual still with more than 3,000 ten thousand tons quantity growth ^[2]The long-term placement of slag not only takies a large amount of good farmlands, destroys ecological; And expose to the sun and rain for a long time and also can cause serious environmental to pollute.At present slag be mainly used in road engineering, build backfill, make steel flux, be used for cement or concrete admixture and be used for field such as sewage disposal as adsorbent, its comprehensive utilization ratio is about 50% ^[2], wherein the overwhelming majority is mainly used in and builds the road and backfill.

Slag is used for absorbing dye Study on wastewater result as adsorbent and shows that slag adsorbs the dye of positive ion easily because of its surface has negative electrical charge, and is poor to the adsorption effect of anionic dye ^[3-7]Wang Wen etc. ^[8]Two kinds of Congo red adsorbing comparative studies on slag of dye of positive ion malachite green, methylene blue and anionic dye have been carried out; The result finds that slag is best to the absorption removal effect of malachite green; Congo red taking second place, and methylene blue is not almost had suction-operated.Xie Fuqing ^[9]Result of study show that also slag to methylene blue dye waste water adsorption capacity extreme difference, has only slag is carried out modification to improve its adsorption activity.This shows; The anion and the dye of positive ion not only depend on the kind of slag surface charge in the absorption on slag surface; And maybe be relevant with the combination of dye molecule and slag, therefore, slag has certain limitation as adsorbent to the absorption of waste water dyestuff.It is worth noting that more dye molecule only is that physical absorption is in slag surface and duct; When the adsorbance that reaches capacity, slag has just lost the effect of adsorption bleaching, needs to handle through methods such as high temperature; Make the dye molecule degraded that is adsorbed in the slag surface, can bring secondary pollution like this.Therefore, how scale, non-secondary pollution, high added value recycling slag are the difficult problems that steel slag utilization faces.

Through consulting number of patents and documents and materials, do not find the preparation of relevant slag based inorganic polymer-oxide semiconductor composite catalyst and this catalyst is used for document and the patent report that dyestuff is degraded.

Below be the list of references that the inventor provides:

[1] Li Liaosha, the historical evolution and the tendency prospect of vessel slag recycling, world steel 4 (2011) 62-67.

[2] Cheng Xu thinks, Yang Quanbing, Multipurpose Utilization of Steel Slag, total utilization of PCA 5 (2010) 45-49.

[3] Zhao Yanfeng, Wang Yan, Liu Lu, slag is handled the experimental study of alkaline fuchsin dye waste water, Changchun University of Science and Technology's journal 34 (4) (2011) 91-93.

[4]A.Bhatnagar,A.K.Jain,A?comparative?adsorption?study?with?different?industrial?wastes?as?adsorbents?for?the?removal?of?cationic?dyes?from?water,J.Colloid?Interface.Sci.281(2004)49-55。

[5]K.R.Ranmakrishna,Dye?removal?us?ing?low?cost?adsorbents,Water?Sci.Technol.36(1997)189-196。

[6] Fan Shisuo, Tang Feng, analogy is careful, Zhang Jun, the application study of slag aspect wastewater treatment, Anhui agricultural sciences 38 (32) (2010) 18282-18283.

[7] Xie Fuqing, Li Jianzhang, slag adsorption and high temperature Regeneration Treatment reactive turquoise blue waste water from dyestuff, chemical industry technology and exploitation 35 (9) (2006) 42-44.

[8] Wang Wen, Xie Li, Wang Shuai, Zhou Qi, characterization of adsorption and mechanism that slag is Congo red to anionic dye, Tongji University's journal 38 (8) (2010) 1182-1187.

[9] Xie Fuqing, modified steel scoria handle the research of methylene blue dye waste water, hosiery industry 1 (2006) 68-70.

Summary of the invention

The objective of the invention is to, the preparation method of a kind of novel slag based inorganic polymer-zinc oxide semi-conductor composite catalyst is provided.And this slag based inorganic polymer-zinc oxide semi-conductor composite catalyst that will make is applied to the frontier of Congo red dyestuff or methylene blue dye waste water degradation reaction.

In order to realize above-mentioned task, the present invention takes following technical solution:

The preparation method of a kind of slag based inorganic polymer-zinc oxide semi-conductor composite catalyst; It is characterized in that; This method is a raw material with the industrial solid castoff slag at first, under the exciting of sodium metasilicate, generates slag based inorganic polymer Binder Materials; Then this slag based inorganic polymer Binder Materials impregnated in the zinc nitrate aqueous solution, form slag based inorganic polymer-zinc oxide semi-conductor composite catalyst through roasting again.

Preparation specifically comprises the following steps:

(1) accurately takes by weighing the slag raw material, insert in the clean slurry mixer;

(2) sodium metasilicate with formula ratio dissolves in the gauge water, and the volume of exciting agent sodium metasilicate is 11% of a raw material weight, and the mass ratio of water and slag is 0.28; Then sodium silicate aqueous solution is added to mix and stir in the clean slurry mixer and form the slurry that mixes;

(3) with the slurry die for molding of packing into, fog room room temperature maintenance 7d is put in the demoulding behind the 1d; Pack in the polybag then and seal; Maintenance 24h under 65 ° of C obtains slag based inorganic polymer Binder Materials, breaks into pieces then; Cross 90 orders～35 mesh sieves, make the slag based inorganic polymer gelling particle of 0.16mm～0.5mm;

(4) accurately take by weighing alkali and excite slag based inorganic polymer gelling particle, pour the Zn (NO of quantitative molar concentration into ₃) ₂6H ₂In the O solution; The load capacity of zinc oxide is 0.5%～10% of a slag based inorganic polymer gelling granular mass; Flood 24h under the room temperature, 65 ℃ of oven dry down, the sample after will drying is again put into Muffle furnace; 500 ℃ of roasting 3h obtain the slag based inorganic polymer-zinc oxide semi-conductor composite catalyst of different zinc oxide load capacity.

Through applicant's evidence, the slag based inorganic polymer-zinc oxide semi-conductor composite catalyst of the present invention preparation can be applied to simulate the degradation reaction of Congo red dyestuff in the industrial wastewater or methylene blue dye waste water.Quantitative inorganic polymer-zinc oxide semi-conductor composite catalyst is put into certain volume, in the simulation industrial wastewater of certain density Congo red or methylene blue dye waste water, under the room temperature, adopt the UV-irradiation certain hour, measure its degradation rate.Specifically comprise the following steps:

(1) measures certain volume, certain density Congo red dyestuff or methylene blue dye simulated wastewater, this solution is moved in the cuvette, measure its absorbance with ultraviolet-visible spectrophotometer with pipette.

(2) quantitative slag based inorganic polymer-zinc oxide composite semiconductor catalyst is put into certain volume, certain density Congo red dyestuff or methylene blue dye simulated wastewater; Shine certain hour with ultraviolet light under the room temperature; Centrifugalize; In the supernatant impouring cuvette in the centrifuge tube, measure its absorbance with ultraviolet-visible spectrophotometer;

(3) measured absorbance after, all reactant liquors and the solid catalyst in the centrifuge tube are reentered in the reactor.

(4) repeating step (2) and step (3) do not change until the absorbance of Congo red dyestuff or methylene blue dye simulated wastewater over time, calculate the degradation rate of Congo red dyestuff or methylene blue dye.

Degradation rate (η) is suc as formula shown in (1):

$\mathrm{\η}=\frac{(A_0-A)}{A_0}\×100\%---\left(1\right)$

In the formula: A ₀Be respectively sample in the initial absorbance at the maximum absorption wavelength 665nm place of the maximum absorption wavelength 498nm place of Congo red dyestuff or methylene blue dye and the absorbance after the different time degraded with A.

The present invention innovates part and is:

(1) proposed to utilize the industrial solid castoff slag to prepare inorganic polymer-zinc oxide semi-conductor composite catalyst, technical process is simple, can realize scale preparation.

(2) proposed slag based inorganic polymer-zinc oxide semi-conductor composite catalyst is applied to the frontier to the degradation rate of Congo red dyestuff or methylene blue dye simulation industrial wastewater; Its degradation rate all can reach 100%, and degradation condition relaxes, and degradation time is short, and efficient is high; Non-secondary pollution can be realized industrial applications.

Description of drawings

Fig. 1 is the flow chart of slag based inorganic polymer of the present invention-zinc oxide semi-conductor composite catalyst preparation;

Fig. 2 is the degradation rate of slag based inorganic polymer-zinc oxide semi-conductor composite catalyst to Congo red dyestuff;

Fig. 3 is the degradation rate of slag based inorganic polymer-zinc oxide semi-conductor composite catalyst to methylene blue dye;

Below in conjunction with accompanying drawing and embodiment the present invention is done further detailed description.Need to prove that these embodiment have been merely the inventor and have better annotated the present invention, the invention is not restricted to these embodiment.

The specific embodiment

Below be the preparation method (Fig. 1) that embodiment provides a kind of slag based inorganic polymer-zinc oxide semi-conductor composite catalyst, the main raw material(s) that is adopted is by the industrial solid castoff slag, and compositions such as chemical activator and zinc nitrate are specific as follows:

1, slag

Select the slag of Laigang group for use, the main chemical quality percentage of described slag consists of: CaO:39.1%, SiO ₂: 17.28%, Fe ₂O ₃: 18.74%, Al ₂O ₃: 4.4%, MgO:4.92%, MnO:3.58%, TiO ₂: 1.52%, V ₂O ₅: 0.93%, SO ₃: 0.31%, BaO:0.2%, K ₂O:0.11%, Na ₂O:0.13%, other: 8.78%;

Through ball milling 2 hours, the density of test slag was 2.91 * 10 ³Kg/m ³, specific area is 398m ²/ kg.

2, chemical activator sodium metasilicate

Adopt and analyze pure sodium silicate solid, molecular formula is: Na ₂SiO ₂9H ₂O.

3, oxide reagent

Adopt and analyze pure solid nitric acid zinc, molecular formula is: Zn (NO ₃) ₂6H ₂O.

Embodiment 1:

Accurately take by weighing slag raw material 1500g, as measurement basis (100%), adopt outer doping, the volume of chemical activator sodium metasilicate is 11% of a slag weight, and the mass ratio of water and slag (also claiming the grain slag ratio) is 0.28.Pouring the slag powder into the two double speeds that change starches only and carries out dispersed with stirring in the mixer; The sodium silicate aqueous solution adding is mixed and stirred, and high-speed stirred forms the slurry that mixes; Slurry is contained in the three gang mould tools of 40mm * 40mm * 160mm, jolt ramming on glue sand plain bumper is wipeed off with scraper plate, obtains the slurry test block of moulding.The demoulding behind the standard curing case maintenance 1d is put in the test block of moulding, put into fog room room temperature maintenance 7d, in the polybag of the sealing of packing into then, maintenance 24h under 65 ° of C, the compression strength of test block is 25MPa, rupture strength is 2.0MPa; Test block is broken into pieces, crossed 90 orders～35 mesh sieves, make the slag based inorganic polymer gelling particle of 0.16mm～0.5mm.

Accurately take by weighing slag based inorganic polymer gelling particle 40g, accurately take by weighing the solid Zn (NO of 0.7345g ₃) ₂6H ₂O, and be dissolved in the distilled water of 20mL; With Zn (NO ₃) ₂6H ₂The O aqueous solution is poured in the slag based inorganic polymer Binder Materials; Flood 24h under the room temperature; 65 ℃ of oven dry down; Sample after will drying is again put into Muffle furnace, 500 ℃ of roasting 3h, and the theoretical negative carrying capacity that obtains ZnO is slag based inorganic polymer-zinc oxide semi-conductor composite catalyst (being labeled as 0.5ZnO-polymer) of 0.5%.

Embodiment 2:

The all operations step is identical with embodiment 1, just takes by weighing solid Zn (NO ₃) ₂6H ₂The amount of O is changed into 7.345g, and is dissolved in the distilled water of 20mL; The theoretical negative carrying capacity that obtains ZnO is slag based inorganic polymer-zinc oxide semi-conductor composite catalyst (being labeled as 5ZnO-polymer) of 5%.

Embodiment 3:

The all operations step is identical with embodiment 1, just takes by weighing solid Zn (NO ₃) ₂6H ₂The amount of O is changed into 14.69g, and is dissolved in the distilled water of 20mL; The theoretical negative carrying capacity that obtains ZnO is 10% inorganic polymer-zinc oxide semi-conductor composite catalyst (being labeled as 10ZnO-polymer).

Embodiment 4:

Compound concentration is the Congo red dyestuff simulated wastewater of 8mg/L, with pipette this solution is moved in the cuvette, measures its absorbance with ultraviolet-visible spectrophotometer.

Accurately take by weighing the catalyst 0.2g that is labeled as 0.5ZnO-polymer among the embodiment 1 and put into the Congo red dyestuff simulated wastewater that 100mL concentration is 8mg/L; Use UV-irradiation 10min under the room temperature; Centrifugalize; In the supernatant impouring cuvette in the centrifuge tube, measure the absorbance that its maximum absorption wavelength (498nm) is located with ultraviolet-visible spectrophotometer.

After measuring absorbance; All reactant liquors and the solid catalyst in the centrifuge tube are reentered in the reactor, and certain hour sampling in every interval centrifugalizes; In the supernatant impouring cuvette in the centrifuge tube, measure its absorbance with ultraviolet-visible spectrophotometer.Repeat this experimental procedure, until the absorbance of Congo red dyestuff simulated wastewater not over time till, utilize degradation rate that formula (1) calculates Congo red dyestuff shown in Fig. 2 and table 1.

Embodiment 5:

All experimental procedures are identical with embodiment 4, and the catalyst change that just will be labeled as 0.5ZnO-polymer is for being labeled as the catalyst of 5ZnO-polymer among the embodiment 2, and the degradation rate of Congo red dyestuff is shown in Fig. 2 and table 1.

Embodiment 6:

All experimental procedures are identical with embodiment 4, and the catalyst change that just will be labeled as 0.5ZnO-polymer is for being labeled as the catalyst of 10ZnO-polymer among the embodiment 3, and the degradation rate of Congo red dyestuff is shown in Fig. 2 and table 1.

Embodiment 7:

All experimental procedures are identical with embodiment 4, and the catalyst change that just will be labeled as 0.5ZnO-polymer is the slag based inorganic polymer catalyst among the embodiment 1, and the degradation rate of Congo red dyestuff is shown in Fig. 2 and table 1.

Embodiment 8:

All experimental procedures are identical with embodiment 4, and the catalyst change that just will be labeled as 0.5ZnO-polymer is the condition experiment of catalyst-free, and the degradation rate of Congo red dyestuff is shown in Fig. 2 and table 1.

Table 1.ZnO-polymer catalyst is to the degradation rate of Congo red dyestuff

Embodiment 9:

Compound concentration is the methylene blue dye simulated wastewater of 2.0mg/L, with pipette this solution is moved in the cuvette, measures its absorbance with ultraviolet-visible spectrophotometer.

Accurately take by weighing the catalyst 0.6g that is labeled as 0.5ZnO-polymer among the embodiment 1 and put into the methylene blue dye dyestuff simulated wastewater that 100mL concentration is 2.0mg/L; Use UV-irradiation 10min under the room temperature; Centrifugalize; In the supernatant impouring cuvette in the centrifuge tube, measure the absorbance that its maximum absorption wavelength (665nm) is located with ultraviolet-visible spectrophotometer.

After measuring absorbance; All reactant liquors and the solid catalyst in the centrifuge tube are reentered in the reactor, and certain hour sampling in every interval centrifugalizes; In the supernatant impouring cuvette in the centrifuge tube, measure its absorbance with ultraviolet-visible spectrophotometer.Repeat this experimental procedure, until the absorbance of methylene blue dye simulated wastewater not over time till, utilize formula (1) to calculate the degradation rate of methylene blue dye, shown in Fig. 3 and table 2.

Embodiment 10:

All experimental procedures are identical with embodiment 9, and the catalyst change that just will be labeled as 0.5ZnO-polymer is for being labeled as the catalyst of 5ZnO-polymer among the embodiment 2, and the degradation rate of methylene blue dye is shown in Fig. 3 and table 2.

Embodiment 11:

All experimental procedures are identical with embodiment 9, and the catalyst change that just will be labeled as 0.5ZnO-polymer is for being labeled as the catalyst of 10ZnO-polymer among the embodiment 3, and the degradation rate of methylene blue dye is shown in Fig. 3 and table 2.

Embodiment 12:

All experimental procedures are identical with embodiment 9, and the catalyst change that just will be labeled as 0.5ZnO-polymer is the slag based inorganic polymer catalyst among the embodiment 1, and the degradation rate of methylene blue dye is shown in Fig. 3 and table 2.

Embodiment 13:

All experimental procedures are identical with embodiment 9, and the catalyst change that just will be labeled as 0.5ZnO-polymer is the condition experiment of catalyst-free, and the degradation rate of methylene blue dye is shown in Fig. 3 and table 2.

The methylene blue dye degradation rate of table 2.ZnO-polymer catalyst

Claims (4)

1. the preparation method of slag based inorganic polymer-zinc oxide semi-conductor composite catalyst; It is characterized in that; This method is a raw material with the industrial solid castoff slag at first, under the exciting of exciting agent sodium metasilicate, generates slag based inorganic polymer Binder Materials; This slag based inorganic polymer Binder Materials impregnated in the zinc nitrate aqueous solution, form slag based inorganic polymer-zinc oxide semi-conductor composite catalyst through roasting again.

2. the method for claim 1 is characterized in that, specifically comprises the following steps:

(1) accurately takes by weighing the slag raw material, insert in the clean slurry mixer;

(2) sodium metasilicate with formula ratio dissolves in the gauge water, and the volume of exciting agent sodium metasilicate is 11% of a raw material weight, and the mass ratio of water and slag is 0.28; Then sodium silicate aqueous solution is added to mix and stir in the clean slurry mixer and form the slurry that mixes;

(3) with the slurry die for molding of packing into, fog room room temperature maintenance 7d is put in the demoulding behind the 1d; Pack into then the sealing polybag in; Maintenance 24h under 65 ° of C obtains slag based inorganic polymer Binder Materials, breaks into pieces then; Cross the 90-35 mesh sieve, make the slag based inorganic polymer gelling particle of 0.16mm～0.5mm;

(4) accurately take by weighing slag based inorganic polymer gelling particle, pour the Zn (NO of quantitative molar concentration into ₃) ₃6H ₂In the O solution; The load capacity of zinc oxide is 0.5%～10% of a slag based inorganic polymer gelling granular mass; Flood 24h under the room temperature, 65 ℃ of oven dry down, the sample after will drying is again put into Muffle furnace; 500 ℃ of roasting 3h obtain the slag based inorganic polymer-zinc oxide semi-conductor composite catalyst of different zinc oxide load capacity.

3. the slag based inorganic polymer-zinc oxide semi-conductor composite catalyst of claim 1 or 2 one of them said method preparation is used for the degradation reaction of Congo red dyestuff or methylene blue dye.

4. application as claimed in claim 3 is characterized in that, adopting wavelength under the room temperature is 254nm, and power is the ZW-2 type electrodeless ultraviolet lamp of 40W, shines the simulated wastewater of Congo red dyestuff or methylene blue dye, carries out photocatalytic degradation, specifically comprises the following steps:

(1) measures the simulation industrial wastewater of certain volume, certain density Congo red dyestuff or methylene blue dye, this solution is moved in the cuvette, measure its absorbance with ultraviolet-visible spectrophotometer with pipette;

(2) quantitative slag based inorganic polymer-zinc oxide composite semiconductor catalyst is put into the simulated wastewater of certain volume, certain density Congo red dyestuff or methylene blue dye; Shine certain hour with ultraviolet light under the room temperature; Centrifugalize; In the supernatant impouring cuvette in the centrifuge tube, measure its absorbance with ultraviolet-visible spectrophotometer;

(3) measured absorbance after, all reactant liquors and solid catalyst are reentered in the reactor;

(4) repeating step (2) and step 3) do not change until the absorbance of the simulated wastewater of Congo red dyestuff or methylene blue dye over time, calculate the degradation rate of Congo red dyestuff or methylene blue dye, and degradation rate (η) is suc as formula shown in (1):

$\mathrm{\η}=\frac{(A_0-A)}{A_0}\×100\%---\left(1\right)$

In the formula: A ₀Be respectively sample in the initial absorbance at the maximum absorption wavelength 665nm place of the maximum absorption wavelength 498nm place of Congo red dyestuff or methylene blue dye and the absorbance after the different time degraded with A.

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