CN104772113B

CN104772113B - A kind of graphene/montmorillonite nano-composite material and preparation method and application

Info

Publication number: CN104772113B
Application number: CN201510106039.6A
Authority: CN
Inventors: 罗汉金; 张子龙
Original assignee: 华南理工大学
Priority date: 2015-03-11
Filing date: 2015-03-11
Publication date: 2017-12-01
Also published as: CN104772113A

Abstract

The invention discloses a kind of graphene/montmorillonite nano-composite material and preparation method and application.The preparation method of graphene/montmorillonite nano-composite material is：Graphene oxide suspension after the modified montmorillonite suspension of cetyl trimethylammonium bromide and supersound process is uniformly mixed, reducing agent is added after being sufficiently stirred to be reduced, black flocculent deposit is obtained after the completion of reaction, scrubbed, suction filtration, dries and obtains graphene/montmorillonite nano-composite material after grinding sieving.Graphene/montmorillonite nano-composite material prepared by the method can be used as adsorbent to be used in field of water pollution control, the particularly Adsorption of heavy metal pollution in wastewater thing, have the advantages that preparation method simplicity, adsorption rate are fast, regeneration is easy and repeatable utilization, and required raw material sources are extensive, cost is low, actual application value is high.

Description

A kind of graphene/montmorillonite nano-composite material and preparation method and application

Technical field

The present invention relates to technical field of water pollution control, and in particular to a kind of graphene/montmorillonite nano-composite material and Its preparation method and application.

Background technology

With the continuous development of industrial economy, the waste water more and more containing heavy metal or organic pollution is discharged into In natural water, ecological environment and human health are seriously endangered.Water pollution problems is many countries in world wide, especially Developing country, the main Environmental Problems faced.China possesses substantial amounts of manufacturing and processing enterprise, and Water Pollution Problem is naturally not Hold optimistic.Heavy metal contaminants in waste water have the characteristics that difficult degradation, toxicity is big and easily accumulates in vivo, to certainly Right environment and the potential hazard of the mankind are huge, therefore the removal to heavy metal pollution in wastewater thing is always that various countries researcher inquires into Focus.Hexavalent chromium is a kind of heavy metal contaminants common in industrial wastewater, and it is widely used in intermetallic composite coating, system In the industries such as leather, plating and pigment manufacture.Cr VI has carcinogenicity, has been listed in one of priority pollutants.For The improvement of hexavalent chromium in waste water, absorption method is in numerous methods so that expense is low, easily operated, effect is good, recyclable heavy The advantages such as metal and adsorbent are renewable turn into conventional method.Up to the present, the researcher of various countries develop it is various not With sorbing material remove the hexavalent chromium in waste water, although some sorbing materials show good adsorption effect, The repeatable utilization rate of these materials is but than relatively low, and this will certainly cause the wasting of resources, increase operating cost, and it is possible to meeting Bring secondary pollution.Graphene is a kind of two-dimension nano materials risen nearly ten years, and huge specific surface area becomes one Kind adsorbent of good performance.But in preparation process, graphene platelet can occur it is irreversible stack again, lose it Most specific surface area, so as to limit application of the graphene as adsorbent in water pollution control.

The content of the invention

An object of the present invention be the removal for Pollutants in Wastewater provide it is a kind of it is economical, environmentally friendly, easily prepared, can The graphene of high recycling rate/montmorillonite nano-composite material adsorbent.

The second object of the present invention is a kind of preparation method for providing above-mentioned graphene/montmorillonite nano-composite material, This method technique is simple, equipment requirement is low, is easy to mass produce.

The third object of the present invention is that provide above-mentioned graphene/montmorillonite nano-composite material is removing as adsorbent The application of hexavalent chromium in heavy metal-containing waste water.

The technical solution used in the present invention is：

A kind of preparation method of graphene/montmorillonite nano-composite material, step are：By cetyl trimethylammonium bromide Modified montmorillonite suspension uniformly mixes with the graphene oxide suspension after being ultrasonically treated, and fully adds after ultrasound, stirring Enter reducing agent to be reduced, black flocculent deposit is obtained after the completion of reaction, scrubbed, suction filtration, dries and is obtained after grinding sieving Graphene/montmorillonite nano-composite material.

The above method comprises the following steps：

(1) oxidation graphite solid is added to the water, graphene oxide suspension is obtained after sonicated；

(2) it is dispersed in water cetyl trimethylammonium bromide is modified montmorillonite used, obtains organically modified montmorillonite clay suspension Liquid；

(3) graphene oxide suspension and organically modified montmorillonite clay suspension that will be obtained in step (1) and step (2) It is homogenously mixed together, uniform, stable suspension is obtained under mechanical agitation and ultrasonication；

(4) by the suspension heating water bath obtained in step (3) to 70 DEG C, reducing agent is added under mechanical agitation, has been reacted Black flocculent deposit is obtained after；

(5) the black flocculent deposit obtained in step (4) washed, filtered, being dried and obtaining stone after grinding sieving Black alkene/montmorillonite nano-composite material.

In the above method, sonication treatment time described in step (1) is 90 ~ 150 min, sonification power is 180 ~ 200 W；The concentration of the graphene oxide suspension is 0.2 ~ 0.3 g/L.

In the above method, the preparation method of organically modified montmorillonite clay suspension is as follows described in step (2)：

Montmorillonite powder is added in cetyl trimethylammonium bromide solution, led under 50 ~ 70 DEG C of water bath condition After crossing the min of mechanic whirl-nett reaction 100 ~ 150, filtering and washing is carried out to product with deionized water, until product in it is not brominated from Son, then product is dispersed in water again, obtains organically modified montmorillonite clay suspension, wherein cetyl trimethylammonium bromide Dosage be 1.0 ~ 1.5 times of montmorillonite cation exchange capacity.

In the above method, mechanical agitation described in step (3) and ultrasonication concretely comprise the following steps：Mechanical agitation and ultrasound The collective effect times of two kinds of effects are 60 min, then the min of mechanical agitation 120 again；Graphene oxide suspension and organic change Property montmorillonite suspension between addition meet：The mass ratio of graphene oxide and montmorillonite is (1 ~ 3)：10.

In the above method, reducing agent described in step (4) is ascorbic acid, and its dosage is the 8 ~ 12 of graphene oxide quality Times.

A kind of graphene/montmorillonite nano-composite material, the graphene/montmorillonite nano-composite material include graphite Alkene, cetyl trimethylammonium bromide and montmorillonite.

Preferably, the cetyl trimethylammonium bromide is inserted between montmorillonite layer by ion exchange；The stone Black alkene is combined together by electrostatic attraction or hydroxyl effect with montmorillonite.

A kind of graphene/montmorillonite nano-composite material is applied to the processing of heavy metal-containing waste water as adsorbent.

In above-mentioned application, the hexavalent chromium removed in heavy metal-containing waste water, comprise the following steps that：

The dosage of graphene/montmorillonite nano-composite material is 3 ~ 6 g/L, and it is 20 ~ 30 DEG C to control wastewater temperature, fully Concussion, adsorbent is separated with waste water after reaching set treatment effect, completes the Adsorption to hexavalent chromium in waste water； The adsorbent of adsorption saturation is desorbed with the mol/L of 0.1 mol/L ~ 1 sodium hydroxide solution, control wastewater temperature for 25 ~ 35 DEG C, fully shaking, adsorbent is recycled after desorption is complete.

Compared with prior art, the beneficial effects of the invention are as follows：

(1) material preparation process of the invention is simple and easy, equipment requirement is low, it is easy to accomplish large-scale mass production；

(2) raw material rich reserves, cheap needed for the present invention, and environment will not be polluted in use, Larger economic benefit can be obtained with relatively low input；

(3) combination of montmorillonite and graphene successfully avoid graphene platelet in reduction process again in the present invention Stack；

(4) graphene/montmorillonite nano-composite material prepared by the present invention can fast and efficiently be inhaled as adsorbent Hexavalent chromium in attached removal waste water, simple method desorption and regeneration can be used after the adsorbent adsorption saturation, realize absorption Agent and the dual recycling of adsorbate, will not only bring secondary pollution, and greatly reduce the processing cost of waste water.

Brief description of the drawings

Fig. 1 is the transmission electron microscope picture of graphene/montmorillonite nano-composite material prepared by embodiments of the invention 1.

Fig. 2 is graphene/montmorillonite nano-composite material and organically-modified illiteracy prepared by embodiments of the invention 1,2 and 3 De- stone, the Fourier transform infrared spectroscopy contrast schematic diagram of montmorillonite.

Fig. 3 is graphene/montmorillonite nano-composite material and organically-modified illiteracy prepared by embodiments of the invention 1,2 and 3 De- stone, the X-ray diffraction contrast schematic diagram of montmorillonite.

Fig. 4 is graphene/montmorillonite nano-composite material prepared by embodiments of the invention 1,2 and 3 and montmorillonite not With under the conditions of solution ph to the adsorbance contrast schematic diagram of hexavalent chromium.

Fig. 5 be embodiments of the invention 3 prepare graphene/montmorillonite nano-composite material from montmorillonite in different absorption To the adsorbance contrast schematic diagram of hexavalent chromium under time conditions.

Fig. 6 is that graphene/montmorillonite nano-composite material prepared by embodiments of the invention 3 adds with montmorillonite in difference To the adsorbance contrast schematic diagram of hexavalent chromium under conditions of amount.

Fig. 7 is that graphene/montmorillonite nano-composite material prepared by embodiments of the invention 3 is tested in 6 wheel adsorption-desorptions In to the adsorbance of hexavalent chromium and desorption degree schematic diagram.

Embodiment

Make further specific detailed description, but embodiments of the present invention are not to the present invention with reference to specific embodiment It is limited to this, for especially not dated technological parameter, can refer to routine techniques progress.

Embodiment 1

(1) 0.25g oxidation graphite solids are added to the water, the oxygen that concentration is 0.25 g/L is obtained after sonicated 2 h Graphite alkene suspension；

Graphite oxide in the present embodiment is prepared using the Hummers methods of improvement, is concretely comprised the following steps：By the 120 ml concentrated sulfuric acids Add 1 L beakers to be placed in ice-water bath, it is slowly stirred with electric mixer, when its temperature is down to 4 DEG C or so, Add 5 g graphite and 2.5 g sodium nitrate, continue stir 30 min after be slowly added to 15 g potassium permanganate, during keep reaction The temperature of system is not higher than 20 DEG C, the min of sustained response 90；Beaker is moved in 35 DEG C of thermostat water bath, treat system temperature liter During to 35 DEG C, continue the min of stirring reaction 30；230 ml deionized waters are persistently slowly added into beaker, control system temperature Below 98 DEG C, heating water bath keeps system temperature at 90 DEG C or so, continues to react after 30 min toward adding 30 ml in beaker 30 ﹪ hydrogen peroxide.Continue stirring until there is no bubble generation in system.Products therefrom is filtered by vacuum, is used in combination 5 ﹪ hydrochloric acid solution washing until no longer sulphate-containing ion in filtrate, then product is carried out with appropriate deionized water from The heart is washed to its pH in neutrality, finally product is placed in 60 DEG C of vacuum drying chamber after drying to constant weight and is obtained the oxidation of brown Graphite solid.

(2) organically modified montmorillonite clay is dispersed in water, its dosage meets：The mass ratio of graphene oxide and montmorillonite For 1:10；

The preparation method of organically modified montmorillonite clay is in the present embodiment：Weigh equivalent to montmorillonite cation exchange capacity (CEC) 1.25 Times cetyl trimethylammonium bromide in 100 ml beakers, adding the ml of deionized water 62.5 makes its dissolving, then toward in solution 2.5 g montmorillonites are added, beaker is placed in thermostat water bath, keeping temperature is 60 DEG C, and electric stirring reacts 2 h.By gained Product is washed with deionized, until not bromine ion-containing in product.

(3) graphene oxide suspension obtained in step (1) is placed in ultrasonic cleaning machine, ultrasound simultaneously uses electric mixing Device is mixed to be stirred it（350 rpm）While be slowly added to the organically modified montmorillonite clay suspension that is obtained in step (2), fill Stirring is divided to make both well mixed；Continual ultrasonic stops ultrasound after stirring 1 h, is followed by stirring for（300 rpm）System is allowed to react 2 H, finally obtain uniform and stable brown suspension；The suspension is washed with deionized and is dispersed in 1 L deionizations afterwards for several times In water；

(4) the brown suspension obtained in step (3) is placed in 70 DEG C of thermostat water bath, and toward in suspension plus Enter ascorbic acid（Graphene oxide is 1 with ascorbic acid mass ratio:10）, electric stirring（200 rpm）90 min are reacted, finally Obtain black product；

(5) by the product obtained in step (4) with deionized water filtering and washing for several times, gained filter cake is placed in forced air drying Dried in case in 50 DEG C to constant weight, grinding, cross 200 mesh sieves, obtain graphene/montmorillonite nano-composite material powder（GCM10）.

Embodiment 2

(1) 0.5g oxidation graphite solids are added to the water, the oxidation that concentration is 0.25 g/L is obtained after sonicated 2h Graphene suspension；

(2) organically modified montmorillonite clay is dispersed in water, addition meets：The mass ratio of graphene oxide and montmorillonite For 2:10；

(4) the brown suspension obtained in step (3) is placed in 70 DEG C of thermostat water bath, and toward in suspension plus Enter appropriate ascorbic acid（Graphene oxide is 1 with ascorbic acid mass ratio:10）, electric stirring（200 rpm）90 min are reacted, Finally give black product；

(5) by the product obtained in step (4) with deionized water filtering and washing for several times, gained filter cake is placed in forced air drying Dried in case in 50 DEG C to constant weight, grinding, cross 200 mesh sieves, obtain graphene/montmorillonite nano-composite material powder（GCM20）.

The preparation method of graphene oxide in the present embodiment is same as Example 1.

The preparation method of organically modified montmorillonite clay in the present embodiment is same as Example 1.

Embodiment 3

(1) 0.75g oxidation graphite solids are added to the water, the oxygen that concentration is 0.25 g/L is obtained after sonicated 2h Graphite alkene suspension；

(2) appropriate organically modified montmorillonite clay is dispersed in water, the dosage of organically modified montmorillonite clay meets：Graphite oxide The mass ratio of alkene and montmorillonite is 3:10；

(5) by the product obtained in step (4) with deionized water filtering and washing for several times, gained filter cake is placed in forced air drying Dried in case in 50 DEG C to constant weight, grinding, cross 200 mesh sieves, obtain graphene/montmorillonite nano-composite material powder（GCM30）.

The effect of embodiment 1-3 products obtained therefroms is shown in that Fig. 1-3, Fig. 1 are the transmission electricity of graphene/montmorillonite nano-composite material Mirror figure, it can be seen that together with montmorillonite particle is successfully incorporated in graphene platelet.Color is dark in figure, profile Clearly demarcated is montmorillonite particle；And material is transparent and have pleated structure is graphene platelet.Fig. 2 is graphene/montmorillonite The Fourier transform infrared spectroscopy figure of nano composite material, as seen from Figure 2, montmorillonite belongs to ten after organically-modified Six alkyl trimethyl ammonium bromide fat connect the symmetrical of c h bond（2850 cm⁻¹）And antisymmetry（2919 cm⁻¹）Stretching vibration peak In the diffraction pattern for appearing in organically modified montmorillonite clay, illustrate that cetyl trimethylammonium bromide is successfully plugged into Montmorillonite Crystal piece Organically modified montmorillonite clay is formed therewith in layer；And in the infrared spectrogram of sample obtained by embodiment 1-3,1725,1572 and 1417 cm⁻¹C=O keys that the diffraction maximum at place is corresponded respectively in the carboxyl not reduced completely on graphene or epoxy functionality The bending of O-H keys on the carboxyl not reduced completely on the characteristic diffraction peak and graphene of phenyl ring in stretching vibration, graphene-structured Vibration, these results prove that graphene is coexisted in the nano composite material with organically modified montmorillonite clay.Fig. 3 is embodiment 1-3 The X-ray diffractogram of gained sample and its raw material, from figure it can be found that montmorillonite after organically-modified its interlamellar spacing by 1.514 nm are expanded to 2.2902 nm, demonstrate again that cetyl trimethylammonium bromide is successfully entered Montmorillonite Crystal interlayer； And with the increase of both graphene, montmorillonite mass ratio in graphene/montmorillonite nano-composite material, the interlamellar spacing of montmorillonite It is gradually reduced, illustrating the introducing of graphene makes a part of cetyl trimethylammonium bromide be discharged between montmorillonite layer, makees For montmorillonite and the connection bridge of graphene, it is combined together both.

Embodiment 4

Test 1

To graphene/montmorillonite nano-composite material under the conditions of different solutions initial pH value to hexavalent chromium in solution Adsorbance is contrasted, and is concretely comprised the following steps：

(1) hexavalent chromium solution for drawing 25 ml difference pH value is separately added into 50 ml conical flask with cover, then 0.15 g Graphene/montmorillonite nano-composite material adds conical flask and stoppers glass stopper, and then conical flask is placed in constant-temperature table；

(2) solution ph in above-mentioned conical flask is respectively 2,4,6,8,10,12, constant-temperature table temperature be set as 25 DEG C, Speed setting is 180 rpm, adsorption time 2h；

(3) adsorbent in each conical flask is separated from solution after above-mentioned adsorption process terminates, completed six in the aqueous solution The Adsorption of valency chromium ion, determine the concentration of remaining hexavalent chromium in solution, calculate adsorbance.

(4) test result is as shown in figure 4, with the reduction of solution ph, graphene/montmorillonite nano-composite material pair The adsorbance of hexavalent chromium gradually increases in solution, shows that acid condition is advantageous to the progress of absorption；Graphene/montmorillonite is received Nano composite material is much larger than montmorillonite original soil to the adsorbance of hexavalent chromium（Mt）.

Test 2

To absorption of the graphene/montmorillonite nano-composite material to hexavalent chromium in solution under the conditions of different adsorption times Amount is contrasted, and is concretely comprised the following steps：

(1) conical flask with cover that 25 ml hexavalent chromium solutions are separately added into 50 ml is drawn, then 0.15 g graphenes/illiteracy De- stone nano composite material（The products obtained therefrom of embodiment 3）Add conical flask and stopper glass stopper, conical flask is then placed in constant temperature In shaking table；

(2) solution ph in above-mentioned conical flask is 2, and constant-temperature table temperature is set as 25 DEG C, speed setting 180 Rpm, adsorption time are respectively 1,3,5,10,20,30,40,60,120,240 min；

(4) test result is as shown in figure 5, with the increase of adsorption time, graphene/montmorillonite nano-composite material pair The adsorbance of hexavalent chromium gradually increases in solution, is received when adsorption time is 2 h close to adsorption equilibrium, graphene/montmorillonite Nano composite material is far superior to montmorillonite original soil to the adsorption effect of hexavalent chromium.

Test 3

To graphene/montmorillonite nano-composite material under the conditions of different adsorbent dosages to hexavalent chromium in solution Adsorbance is contrasted, and is concretely comprised the following steps：

(1) batch draws the hexavalent chromium solution that 25ml initial concentrations are 50 ppm, initial pH value is 2 and adds 50 ml In conical flask with cover, appropriate adsorbent is then put into successively（The products obtained therefrom of embodiment 3）；

(2) above-mentioned adsorbent dosage is respectively 2,4,8,12,16 g/L and 20 g/L, and all conical flask with cover are united One be placed in 25 DEG C of temperature, the rpm of rotating speed 180 constant-temperature table in, shake 2 h after take out；

(4) test result is as shown in fig. 6, with the increase of adsorbent dosage, the clearance of hexavalent chromium in solution Also continue to increase, when dosage is 8 g/L, clearance reaches more than 90%.

Test 4

Desorption and regeneration is carried out to graphene/montmorillonite nano-composite material of adsorption saturation, concretely comprised the following steps：

(1) toward sodium hydroxide solution is added in the conical flask of the adsorbent equipped with adsorption saturation, stoppering will be all after bottle stopper Conical flask, which is uniformly placed in constant-temperature table, to be shaken；

(2) concentration of above-mentioned sodium hydroxide solution is respectively 0.1 mol/L, and constant-temperature table temperature is 30 DEG C, rotating speed is 180 rpm, concussion time are 1.5 h；

(3) adsorbent in each conical flask is separated from solution after above-mentioned desorption process terminates, determines and is eluted in solution The concentration of the hexavalent chromium gone out, calculate desorption rate.

(4) test result as shown in fig. 7, by 6 wheel adsorption-desorptions experiment after its to hexavalent chromium still have it is good Good adsorption capacity, it is only 13% that adsorbance, which declines, illustrates that graphene/montmorillonite nano-composite material has good reproducibility Can, it can be generalized to as a kind of excellent adsorbent in practical application.

The above embodiment of the present invention is only intended to clearly illustrate example of the present invention, and is not to the present invention Embodiment restriction.For those of ordinary skill in the field, can also make on the basis of the above description Other various forms of changes or variation.There is no necessity and possibility to exhaust all the enbodiments.It is all the present invention All any modification, equivalent and improvement made within spirit and principle etc., should be included in the protection of the claims in the present invention Within the scope of.

Claims

A kind of 1. preparation method of graphene/montmorillonite nano-composite material, it is characterised in that：By cetyl trimethyl bromination Graphene oxide suspension after the modified montmorillonite suspension of ammonium and supersound process uniformly mixes, fully after ultrasound, stirring Add reducing agent to be reduced, black flocculent deposit is obtained after the completion of reaction, after scrubbed, suction filtration, dry and grinding sieving To graphene/montmorillonite nano-composite material.
2. the preparation method of graphene/montmorillonite nano-composite material according to claim 1, it is characterised in that including such as Lower step：(1) oxidation graphite solid is added to the water, graphene oxide suspension is obtained after sonicated；(2) by hexadecane Base trimethylammonium bromide is modified montmorillonite used to be dispersed in water, and obtains organically modified montmorillonite clay suspension；(3) by step (1) and step Suddenly the graphene oxide suspension and organically modified montmorillonite clay uniform suspension obtained in (2) mixes, in mechanical agitation With the suspension that uniform stabilization is obtained under ultrasonication；(4) by the suspension heating water bath obtained in step (3) to 70 DEG C, machine Tool stirring is lower to add reducing agent, and black flocculent deposit is obtained after the completion of reaction；(5) it is cotton-shaped to the black obtained in step (4) heavy Graphene/montmorillonite nano-composite material is obtained after shallow lake is washed, filtered, dried and grinding is sieved.
3. the preparation method of graphene/montmorillonite nano-composite material according to claim 2, it is characterised in that：Step (1) sonication treatment time described in is 90 ~ 150min, and sonification power is 180 ~ 200W；The graphene oxide suspension Concentration be 0.2 ~ 0.3g/L.
4. the preparation method of graphene/montmorillonite nano-composite material according to claim 2, it is characterised in that：Step (2) preparation method of organically modified montmorillonite clay suspension described in is as follows：Montmorillonite powder is added to cetyl trimethyl In ammonium bromide solution, under 50 ~ 70 DEG C of water bath condition by 100 ~ 150min of mechanic whirl-nett reaction after, with deionized water to production Thing carries out filtering and washing, until product, is then dispersed in water by not bromine ion-containing in product again, obtains organically-modified cover and takes off The dosage of stone suspension, wherein cetyl trimethylammonium bromide is 1.0 ~ 1.5 times of montmorillonite cation exchange capacity.
5. the preparation method of graphene/montmorillonite nano-composite material according to claim 2, it is characterised in that：Step (3) mechanical agitation described in and ultrasonication concretely comprise the following steps：The collective effect time of two kinds of effects of mechanical agitation and ultrasound For 60min, subsequent mechanical agitation 120min again；Addition between graphene oxide suspension and organically modified montmorillonite clay suspension Amount meets：The mass ratio of graphene oxide and montmorillonite is (1 ~ 3)：10.
6. the preparation method of graphene/montmorillonite nano-composite material according to claim 2, it is characterised in that：Step (4) reducing agent described in is ascorbic acid, and its dosage is 8 ~ 12 times of graphene oxide quality.
7. a kind of graphene/montmorillonite nano-composite material that any one of claim 1 ~ 6 preparation method is prepared, its It is characterised by：Graphene/the montmorillonite nano-composite material includes graphene, cetyl trimethylammonium bromide and Meng Tuo Stone.
8. graphene/montmorillonite nano-composite material according to claim 7, it is characterised in that：The cetyl three Methyl bromide ammonium is inserted between montmorillonite layer by ion exchange；The graphene by electrostatic attraction or hydroxyl effect with Montmorillonite is combined together.
9. graphene/montmorillonite nano-composite material described in claim 7 is as adsorbent in heavy metal-containing wastewater treatment Application.
10. the application of graphene/montmorillonite nano-composite material according to claim 9, it is characterised in that：For removing Hexavalent chromium in heavy metal-containing waste water, is comprised the following steps that：The dosage of graphene/montmorillonite nano-composite material be 3 ~ 6g/L, it is 20 ~ 30 DEG C to control wastewater temperature, fully shaking, is separated adsorbent with waste water after reaching set treatment effect, complete The Adsorption of hexavalent chromium in paired waste water；With suction of the 0.1mol/L ~ 1mol/L sodium hydroxide solution to adsorption saturation Attached dose is desorbed, and it is 25 ~ 35 DEG C to control wastewater temperature, fully shaking, recycles adsorbent after desorption is complete.