CN108905954B - Preparation method and application of manganese dioxide modified sepiolite adsorbent - Google Patents

Preparation method and application of manganese dioxide modified sepiolite adsorbent Download PDF

Info

Publication number
CN108905954B
CN108905954B CN201810561633.8A CN201810561633A CN108905954B CN 108905954 B CN108905954 B CN 108905954B CN 201810561633 A CN201810561633 A CN 201810561633A CN 108905954 B CN108905954 B CN 108905954B
Authority
CN
China
Prior art keywords
sepiolite
acid
manganese dioxide
adsorbent
solution
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN201810561633.8A
Other languages
Chinese (zh)
Other versions
CN108905954A (en
Inventor
胡夏一
张刚
周业丰
陈洪波
罗潇
赵铁光
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Xiangtan University
Original Assignee
Xiangtan University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Xiangtan University filed Critical Xiangtan University
Priority to CN201810561633.8A priority Critical patent/CN108905954B/en
Publication of CN108905954A publication Critical patent/CN108905954A/en
Application granted granted Critical
Publication of CN108905954B publication Critical patent/CN108905954B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
    • B01J20/02—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material
    • B01J20/10—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material comprising silica or silicate
    • B01J20/12—Naturally occurring clays or bleaching earth
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
    • B01J20/02—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material
    • B01J20/06—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material comprising oxides or hydroxides of metals not provided for in group B01J20/04
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/28—Treatment of water, waste water, or sewage by sorption
    • C02F1/288—Treatment of water, waste water, or sewage by sorption using composite sorbents, e.g. coated, impregnated, multi-layered
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2101/00—Nature of the contaminant
    • C02F2101/10—Inorganic compounds
    • C02F2101/20—Heavy metals or heavy metal compounds
    • C02F2101/22—Chromium or chromium compounds, e.g. chromates

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Inorganic Chemistry (AREA)
  • Analytical Chemistry (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Dispersion Chemistry (AREA)
  • Hydrology & Water Resources (AREA)
  • Engineering & Computer Science (AREA)
  • Environmental & Geological Engineering (AREA)
  • Water Supply & Treatment (AREA)
  • Silicates, Zeolites, And Molecular Sieves (AREA)
  • Solid-Sorbent Or Filter-Aiding Compositions (AREA)

Abstract

The invention discloses a preparation method and application of manganese dioxide modified sepiolite adsorbent. The preparation method comprises the steps of purifying the sepiolite, carrying out acid treatment on the sepiolite and modifying the sepiolite manganese dioxide subjected to the acid treatment, namely treating the sepiolite by using acid, carrying out liquid-phase oxidation reduction by using potassium permanganate and concentrated hydrochloric acid to generate manganese dioxide, and loading the sepiolite subjected to the acid treatment by using a proper amount of manganese dioxide. The method has simple process, the obtained adsorbent effectively combines the advantages of manganese dioxide and solid adsorbent, the adsorption performance of the adsorbent is obviously improved, the adsorption effect is good, the adsorbent is particularly suitable for removing heavy metal ions, the price is cheaper than other solid adsorbents, the production cost is obviously reduced, and the method is more favorable for large-scale and industrial development.

Description

Preparation method and application of manganese dioxide modified sepiolite adsorbent
Technical Field
The invention belongs to the field of adsorbent preparation, and particularly relates to a preparation method and application of manganese dioxide modified sepiolite adsorbent.
Background
The ecological environment problem caused by water body pollution along with the discharge of heavy metal ions is increasingly severe, and Cd2+How to remove is receiving more and more attention. In Cd2+The emission sources of (a) are mainly from the emissions of mechanical processing, mining industry, steel and non-ferrous metal smelting and some chemical enterprises.
Industrial Cd2+The removal method of (b) is selected from precipitation, ion exchange, adsorption, membrane separation, biological method, etc. The adsorption method is a method which is researched more and widely applied at present due to the characteristics of simple operation, low cost, small secondary pollution and reutilization of the adsorbent. The natural ore in the adsorbent is widely distributed, cheap and easily available, and is an adsorption material with considerable prospect in environmental remediation.
Sepiolite is a fibrous magnesium-rich silicate natural clay mineral with an ideal crystal unit molecular formula of Mg8(Si12O30)(OH)4·12H2O, it has structural unit of layer chain structure formed by alternative arrangement of magnesium oxygen octahedron and silicon oxygen tetrahedron, possess the pore canal identical with fiber direction in the fiber that this kind of structure makes up, the pore canal size is 0.38nm x 0.94nm, is full of the hydrone (pore canal water) in the pore canal; on the outer surface of the fibre, these channels form channels, each along the edge of the fibre
Figure BDA0001683412970000011
A silane (Si-OH) group is distributed; there are also OH groups projecting from the fiber ends, which are bonded to the oxygen atoms in the magnesiooctahedron. The structure enables the sepiolite to have uniform pore diameter, higher specific surface area and excellent ion exchange capacity.
Manganese dioxide is used as a transition metal oxide with adsorption capacity, has large specific surface area, many surface adsorption sites, negative charges on the surface, high porosity, small particle size and high adsorption activity, and has strong adsorption and enrichment effects on heavy metals. The method selects cheap solid adsorbent with excellent properties and loads manganese dioxide to reduce Cd2+Adsorbent cost, an important measure that increases the possibilities for industrial applications. These properties make sepiolite the choice solid adsorbent supported on manganese dioxide.
At present, researchers at home and abroad carry out researches on the aspects of adsorbing heavy metals and dyes by manganese dioxide loaded ores and the like. Eren et al (depletion and Water Treatment 2010,20, 114-122) applied to adsorption of Cu in aqueous solution by manganese dioxide modified sepiolite produced by manganese dichloride and sodium hydroxide under alkaline condition2+Under appropriate conditions the maximum adsorption increased from 5.55mg/g unmodified to 6.70mg/g modified. Runping Han et al (Journal of Hazardous Materials 2006,137, 934. 942.) use manganese dioxide coated silica sand produced by the reaction of potassium permanganate with concentrated hydrochloric acid to fill an adsorption column to remove Cu from aqueous solution2+And Pb2+For Pb under optimum adsorption conditions2+The adsorption capacity of the copper-based catalyst reaches 0.365mmol/g, and the copper-based catalyst is applied to Cu2+The amount of adsorbed substances was 0.125 mmol/g. Ahmet Sarl et al (Microporous and Mesoporous Materials 20)13,170,155-+The adsorption capacity was increased from the original 46.2mg/g unmodified to the modified 69.2 mg/g.
In the above study, e.eren performed MnO on sepiolite2Before and after modification, the adsorption performance is not improved well. Although Runping Han and Ahmet Sarl subject the material to MnO2After modification, the heavy metal ion adsorption is improved, but the improvement range is not large because MnO generated under the alkaline preparation condition2Doped with a large amount of Mn (OH)2The adsorption effect is affected.
Disclosure of Invention
Aiming at the defects of the prior art, the invention aims to provide a preparation method of a manganese dioxide modified sepiolite adsorbent and application of the manganese dioxide modified sepiolite adsorbent in adsorbing metal ions in an aqueous solution.
In order to achieve the above purpose, the invention provides the following technical scheme:
adding acid-treated sepiolite into permanganate solution to obtain mixed solution, heating, and adding H dropwise into the mixed solution+And (3) adding an acid solution A with the concentration of more than or equal to 6mol/L, continuing the reaction after the dropwise adding is finished, and carrying out solid-liquid separation to obtain a solid, namely the manganese dioxide modified sepiolite adsorbent.
In a preferred embodiment, the liquid-solid volume-to-mass ratio of the permanganate solution to the acid-treated sepiolite is 10-30: 1(ml: g).
In a preferred embodiment, the permanganate is potassium permanganate.
In the preferred scheme, the mass ratio of the sepiolite subjected to acid treatment to the manganese element in the mixed solution is as follows: 1.5-8: 1.
more preferably, the mass ratio of the acid-treated sepiolite to the manganese element in the mixed solution is: 1.95-4: 1.
According to the preferable scheme, the mixed solution is obtained, after the mixed solution is heated and stirred at the temperature of 80-100 ℃ for 20-30 min, the acid solution A is dropwise added into the mixed solution, and the temperature is kept at 80-100 ℃ in the dropwise adding process.
The inventors have found that preheating for a period of time and then adding acid solution a dropwise can accelerate the reaction rate and promote the conversion of permanganate to manganese dioxide.
In the present invention, a water bath heating method is preferably used.
In a preferred embodiment, the acid solution a is hydrochloric acid.
In a preferable scheme, the mass fraction of HCL dissolved in the hydrochloric acid is 20-38%
More preferably, the mass fraction of HCL dissolved in the hydrochloric acid is 36% to 38%.
In a preferable scheme, the liquid-solid volume mass ratio of the hydrochloric acid to the potassium permanganate is 2-2.5: 1(ml: g);
more preferably, the liquid-solid volume mass ratio of the hydrochloric acid to the potassium permanganate is 2.1-2.2: 1(ml: g).
Preferably, the dropping speed is 0.15-0.8 ml/min.
More preferably, the dropping speed is 0.25 to 0.55 ml/min.
The inventors found that too high a dropping rate leads to formation of MnO2Suspended in the solution and can not be smoothly loaded on the sepiolite.
In a preferable scheme, the reaction temperature is 80-100 ℃, and the reaction time is 2-3 h.
Preferably, the solid-liquid separation is carried out, the obtained solid is washed by deionized water until the supernatant is colorless, and the solid is dried and ground to obtain the manganese dioxide modified sepiolite adsorbent.
Preferably, the drying temperature is 60-110 ℃, and the drying time is 12-48 h.
In a preferable scheme, the mass of manganese dioxide in the manganese dioxide modified sepiolite is 20-100% of the mass of the sepiolite.
More preferably, the mass of the manganese dioxide in the manganese dioxide modified sepiolite adsorbent is 40-80% of the mass of the sepiolite.
In a preferred embodiment, the preparation method of the acid-treated sepiolite comprises the following steps: mixing the sepiolite with the acid solution B to obtain a suspension, standing, separating supernatant, washing the lower layer, performing solid-liquid separation, drying, grinding, sieving with a 120-mesh sieve, and taking undersize products to obtain the acid-treated sepiolite.
In a preferred embodiment, H in the acid solution B+The concentration of (A) is 0.04-6 mol/L;
further preferably, H in the acid solution B+The concentration of (b) is 0.34-4 mol/L.
Preferably, the acid solution B is at least one selected from hydrochloric acid, sulfuric acid, and nitric acid.
In a preferable scheme, the mass ratio of the sepiolite to the acid solution B is 1: 5-30.
Preferably, the standing time is 12-48 h.
In the preferable scheme, the purity of the sepiolite is more than or equal to 70 percent. More preferably, the sepiolite has a purity of 90% or more.
In a preferable scheme, the sepiolite is obtained by purifying raw sepiolite ore.
As a further preferred method, the method of the purification treatment is a physical sedimentation method, and the specific method refers to patent (CN 106745014A).
The manganese dioxide modified sepiolite adsorbent prepared by the preparation method is applied to adsorbing metal ions in an aqueous solution.
Further, the manganese dioxide modified sepiolite adsorbent prepared by the preparation method can adsorb Cd in an aqueous solution2+The use of (1).
Preferably, the pH of the aqueous solution is 2 to 7.
Further preferably, the pH of the aqueous solution is 3 to 6.
The principle and advantages of the invention are as follows:
in the invention, the sepiolite is firstly treated by acid, and when the acid is contacted with the sepiolite, on one hand, carbonate impurities in the sepiolite are removed, and the pore volume is increased; on the other hand H in acid+The sepiolite replaces Mg atoms in Mg-O octahedrons in the structure, changes Si-O-Mg-O-Si bonds into two Si-O-H bonds, connects internal channels and increases the surface area.
And then further modifying the sepiolite subjected to acid treatment by manganese dioxide, and loading manganese dioxide generated by the reaction of potassium permanganate and concentrated hydrochloric acid on the sepiolite by a liquid-phase oxidation-reduction method.
The acidic process condition of the invention has the advantages of large manganese dioxide adsorption capacity and stable load strength, can provide more active sites compared with alkaline conditions, has the characteristic of strong adsorption capacity, has stable property, and is suitable for being used in the actual production process.
In aqueous solution, manganese oxide undergoes surface hydroxylation to obtain Cd2+Provides a specific adsorption site. In addition, the pore structure of the sepiolite is that manganese dioxide adsorbs Cd2+An adsorption site is provided. The manganese dioxide sepiolite adsorbent prepared by the preparation method is used for Cd in aqueous solution2+The adsorption of (2) has good effect.
The method has the advantages of simple process and mild reaction conditions, the obtained adsorbent effectively combines the advantages of manganese dioxide and solid adsorbent, the adsorption performance of the adsorbent is obviously improved, the adsorption effect is good, and the method is particularly suitable for Cd in water2+Compared with other solid adsorbents as immobilized materials, the solid adsorbent has the advantages of lower price, obvious reduction of production cost and contribution to large-scale and industrial development.
Drawings
FIG. 1 is a block diagram of the process flow of the present invention.
FIG. 2 is a graph comparing FTIR of the adsorbent prepared in example 1 with sepiolite ore.
FIG. 3 is a graph showing the adsorption profile of the adsorbent prepared in example 1.
Detailed Description
The present invention will be further described with reference to the following examples.
Example 1
A preparation method of manganese dioxide modified sepiolite adsorbent comprises the steps of treating purified sepiolite for a period of time by using potassium permanganate solution with certain concentration, and then combining manganese dioxide and sepiolite in a certain proportion by using a liquid-phase oxidation-reduction method on the basis to prepare manganese dioxide composite modified sepiolite adsorption material; the method specifically comprises the following steps:
(1) purification of sepiolite (reference patent publication No. CN106745014A)
a. Weighing 20g of sepiolite raw ore, adding 400mL of deionized water, and stirring for 3h at normal temperature;
b. and after stirring, pouring the mixture into a separating funnel, standing for layering, taking the lower layer, adding water to 400mL, stirring for 1h, pouring the mixture into the separating funnel again, standing for layering, and repeating the steps for several times until the layering is avoided. 0.48g of sodium hexametaphosphate was added, and after stirring for 3 hours, the mixture was allowed to stand for 48 hours.
c. Taking the upper layer of the slurry after standing for 48 hours, centrifugally separating, drying in a drying oven at 108 ℃ for 24 hours, and grinding to obtain the purified sepiolite. The purity of the obtained purified sepiolite was 90%.
(2) Acid treatment of purified sepiolite
a. Mixing 5g of purified sepiolite with 100ml of hydrochloric acid with the mass fraction of 0.34mol/L, and standing for 48 hours;
b. after the completion of the standing, the supernatant was poured off, the lower layer was repeatedly washed with deionized water 3 times, and finally the pH was adjusted to neutral with NaOH.
c. And centrifugally separating the washed suspension to obtain acid-treated sepiolite precipitate, drying for 24 hours, and grinding to obtain the acid-treated sepiolite.
(3) Modification of acid treated and purified sepiolite manganese dioxide
A. Preparing 100mL solution of 7.264g potassium permanganate into 5g HCl modified sepiolite, heating and stirring in a 100 ℃ constant temperature water bath kettle for 30min, slowly dripping 15.36mL concentrated hydrochloric acid after 30min, and finishing dripping within 30 min;
B. after the dropwise addition, the water bath heating and stirring state was maintained for 2 hours, and then the heating and stirring were stopped. Standing for layering, pouring out supernatant, repeatedly washing lower layer with deionized water for several times, drying in an oven at 80 deg.C for 12 hr, and grinding to obtain sample.
FIG. 2 is sepiolite and 80% MnO2FTIR spectra of sepiolite, from a comparison graph, at 517cm-1The band appearing at (B) represents the vibration of the Mn-O bond, 3429cm-1And 1643cm-1Respectively represent the stretching vibration and the bending vibration of O-H in zeolite water, 3686cm-1And 642cm-1Respectively represent the elongation of Mg-OH in a trioctahedronShrinkage vibration and bending vibration, 3559cm represents stretching vibration combined with O-H in water, 1079cm-1Representing stretching vibration of Si-OH, 472cm-1Representing the bending vibration of O-Si-O. In view of the change between them, MnO2Successfully loaded on the sepiolite.
The sepiolite obtained in the above embodiment is used for wastewater treatment, and the specific method is as follows:
firstly, preparing a series of Cd with different concentrations2+Is a solution, and the working solution is prepared by the method. Adding modified sepiolite into the solution, adjusting pH to 6, oscillating at constant temperature for 4 hr, centrifuging to obtain supernatant, and removing residual Cd2+The concentration is determined by an atomic absorption spectrophotometer according to Cd in the working solution before and after adsorption2+Calculating the concentration of the modified sepiolite to the heavy metal Cd2+The amount of adsorption of (3). The obtained solid adsorbent is used for Cd2+The adsorption capacity is greatly improved from the original 6.26mg/g to 43.65 mg/g.
Example 2
(1) Purification of sepiolite (reference patent publication No. CN106745014A)
a. Weighing 20g of sepiolite raw ore, adding 400mL of deionized water, and stirring for 3h at normal temperature;
b. and after stirring, pouring the mixture into a separating funnel, standing for layering, taking the lower layer, adding water to 400mL, stirring for 1h, pouring the mixture into the separating funnel again, standing for layering, and repeating the steps for several times until the layering is avoided. 0.48g of sodium hexametaphosphate was added, and after stirring for 3 hours, the mixture was allowed to stand for 48 hours.
c. Taking the upper layer of the slurry after standing for 48 hours, centrifugally separating, drying in a drying oven at 108 ℃ for 24 hours, and grinding to obtain the purified sepiolite, wherein the purity of the obtained purified sepiolite is 90%.
(2) Acid treatment of purified sepiolite
a. Weighing 5g of purified sepiolite, adding 150ml of H with the concentration of 2mol/l2SO4Processing for 24 hours at normal temperature;
b. after the treatment is finished, centrifugally separating to remove the upper layer liquid, taking out the lower layer, adding deionized water, continuously stirring for a period of time, centrifugally separating to remove the upper layer liquid, repeating the steps for 3 times, and finally adjusting the pH value to be neutral by using NaOH;
c. and (4) centrifugally separating the suspension with the pH adjusted to be neutral to obtain acid-treated sepiolite precipitate, drying for 24 hours, and grinding to obtain the acid-treated sepiolite.
(3) Modification of acid treated and purified sepiolite manganese dioxide
A. And (2) preparing 3.632g of potassium permanganate into 100ml of solution, adding 5g of the acid-treated sepiolite sample obtained in the step (1), heating and stirring in a constant-temperature water bath kettle at 100 ℃ for 30min, dropwise adding 7.68ml of concentrated hydrochloric acid after 30min, and dropwise adding within 30min to complete the preparation.
B. After the dropwise addition, the water bath heating and stirring state was maintained for 2 hours, and then the heating and stirring were stopped. Standing for layering, pouring out supernatant, repeatedly washing lower layer with deionized water for several times, drying in an oven at 80 deg.C for 12 hr, and grinding to obtain sample.
Using the same characterization as in example 1, MnO was obtained2Successfully loaded on the acid modified sepiolite to obtain the adsorbent pair Cd2+The adsorption capacity of the adsorbent is greatly improved from the original 6.26mg/g to 34.67 mg/g.
Example 3
(1) Purification of sepiolite (reference patent publication No. CN106745014A)
a. Weighing 20g of sepiolite raw ore, adding 400mL of deionized water, and stirring for 3h at normal temperature;
b. and after stirring, pouring the mixture into a separating funnel, standing for layering, taking the lower layer, adding water to 400mL, stirring for 1h, pouring the mixture into the separating funnel again, standing for layering, and repeating the steps for several times until the layering is avoided. 0.48g of sodium hexametaphosphate was added, and after stirring for 3 hours, the mixture was allowed to stand for 48 hours.
c. Taking the upper layer of the slurry after standing for 48 hours, centrifugally separating, drying in a drying oven at 110 ℃ for 24 hours, and grinding to obtain the purified sepiolite, wherein the purity of the obtained purified sepiolite is 90%.
(2) Acid treatment of purified sepiolite
a. Weighing 5g of purified sepiolite, adding 100ml of HNO with the concentration of 0.5mol/l3Treating at normal temperature for 12 h;
b. after the treatment is finished, centrifugally separating to remove the upper layer liquid, taking out the lower layer, adding deionized water, continuously stirring for a period of time, centrifugally separating to remove the upper layer liquid, repeating the steps for 3 times, and finally adjusting the pH value to be neutral by using NaOH;
c. and (3) centrifugally separating the suspension with the pH adjusted to be neutral to obtain acid-treated sepiolite precipitate, drying the acid-treated sepiolite precipitate until the acid-treated sepiolite precipitate is anhydrous, roasting the dried acid-treated sepiolite precipitate at 200 ℃ for 10 hours, and grinding the dried acid-treated sepiolite precipitate to obtain the acid-treated sepiolite.
(3) Modification of acid treated and purified sepiolite manganese dioxide
A. And (2) preparing 5.448g of potassium permanganate into 100ml of solution, adding 5g of the acid-treated sepiolite sample obtained in the step (1), heating and stirring in a constant-temperature water bath kettle at 100 ℃ for 30min, dropwise adding 11.52ml of concentrated hydrochloric acid after 30min, and dropwise adding within 30 min.
B. After the dropwise addition, the water bath heating and stirring state was maintained for 2 hours, and then the heating and stirring were stopped. Standing for layering, pouring out supernatant, repeatedly washing lower layer with deionized water for several times, drying in an oven at 80 deg.C for 12 hr, and grinding to obtain sample. Using the same characterization as in example 1, MnO was obtained2Successfully loaded on the acid modified sepiolite to obtain the adsorbent pair Cd2+The adsorption capacity of the adsorbent is greatly improved from the original 6.26mg/g to 30.85 mg/g.
Comparative example 1
(1) Sepiolite purification (other conditions are the same as those in example 1 by reference to the patent publication, only sepiolite is purified without hydrochloric acid treatment in advance.
(1) Purification of sepiolite (reference patent publication No. CN106745014A)
a. Weighing 20g of sepiolite raw ore, adding 400mL of deionized water, and stirring for 3h at normal temperature;
b. and after stirring, pouring the mixture into a separating funnel, standing for layering, taking the lower layer, adding water to 400mL, stirring for 1h, pouring the mixture into the separating funnel again, standing for layering, and repeating the steps for several times until the layering is avoided. 0.48g of sodium hexametaphosphate was added, and after stirring for 3 hours, the mixture was allowed to stand for 48 hours.
c. Taking the upper layer of the slurry after standing for 48 hours, centrifugally separating, drying in a drying oven at 108 ℃ for 24 hours, and grinding to obtain the purified sepiolite.
(2) Modification of purified sepiolite manganese dioxide
A. Preparing 100mL solution of 7.264g potassium permanganate into 5g HCl modified sepiolite, heating and stirring in a 100 ℃ constant temperature water bath kettle for 30min, slowly dripping 15.36mL concentrated hydrochloric acid after 30min, and finishing dripping within 30 min;
B. after the dropwise addition, the water bath heating and stirring state was maintained for 2 hours, and then the heating and stirring were stopped. Standing for layering, pouring out supernatant, repeatedly washing lower layer with deionized water for several times, drying in an oven at 80 deg.C for 12 hr, and grinding to obtain sample.
The sepiolite obtained in the above embodiment is used for wastewater treatment, and the specific method is as follows:
firstly, preparing a series of Cd with different concentrations2+Is a solution, and the working solution is prepared by the method. Adding modified sepiolite into the solution, adjusting pH to 6, oscillating at constant temperature for 4 hr, centrifuging to obtain supernatant, and removing residual Cd2+The concentration is determined by an atomic absorption spectrophotometer according to Cd in the working solution before and after adsorption2+Calculating the concentration of the modified sepiolite to the heavy metal Cd2+The amount of adsorption of (3). The obtained solid adsorbent is used for Cd2+The adsorption capacity is greatly improved from the original 6.26mg/g to 25.15 mg/g.
Comparative example 2
Other conditions were the same as in example 1, and only sepiolite was not subjected to the purification treatment in advance. The specific experimental steps are as follows:
(1) acid treatment of sepiolite
a. Mixing 5g of sepiolite and 100ml of hydrochloric acid with the mass fraction of 0.34mol/L, and standing for 48 hours;
b. after the completion of the standing, the supernatant was poured off, the lower layer was repeatedly washed with deionized water 3 times, and finally the pH was adjusted to neutral with NaOH.
c. And centrifugally separating the washed suspension to obtain acid-treated sepiolite precipitate, drying for 24 hours, and grinding to obtain the acid-treated sepiolite.
(2) Modification of acid-treated sepiolite manganese dioxide
A. Preparing 100mL solution of 7.264g potassium permanganate into 5g HCl modified sepiolite, heating and stirring in a 100 ℃ constant temperature water bath kettle for 30min, slowly dripping 15.36mL concentrated hydrochloric acid after 30min, and finishing dripping within 30 min;
B. after the dropwise addition, the water bath heating and stirring state was maintained for 2 hours, and then the heating and stirring were stopped. Standing for layering, pouring out supernatant, repeatedly washing lower layer with deionized water for several times, drying in an oven at 80 deg.C for 12 hr, and grinding to obtain sample.
The sepiolite obtained in the above embodiment is used for wastewater treatment, and the specific method is as follows:
firstly, preparing a series of Cd with different concentrations2+Is a solution, and the working solution is prepared by the method. Adding modified sepiolite into the solution, adjusting pH to 6, oscillating at constant temperature for 4 hr, centrifuging to obtain supernatant, and removing residual Cd2+The concentration is determined by an atomic absorption spectrophotometer according to Cd in the working solution before and after adsorption2+Calculating the concentration of the modified sepiolite to the heavy metal Cd2+The amount of adsorption of (3). The obtained solid adsorbent is used for Cd2+The adsorption capacity of the adsorbent is improved to 16.93mg/g from the original 6.26 mg/g.
Comparative example 3
Other conditions were the same as in example 1, and the mass of the purified sepiolite supported MnO2 which was only acid-treated was 10% of its mass, and the specific experimental procedure was as follows:
(1) purification of sepiolite (reference patent publication No. CN106745014A)
a. Weighing 20g of sepiolite raw ore, adding 400mL of deionized water, and stirring for 3h at normal temperature;
b. and after stirring, pouring the mixture into a separating funnel, standing for layering, taking the lower layer, adding water to 400mL, stirring for 1h, pouring the mixture into the separating funnel again, standing for layering, and repeating the steps for several times until the layering is avoided. 0.48g of sodium hexametaphosphate was added, and after stirring for 3 hours, the mixture was allowed to stand for 48 hours.
c. Taking the upper layer of the slurry after standing for 48 hours, centrifugally separating, drying in a drying oven at 108 ℃ for 24 hours, and grinding to obtain the purified sepiolite.
(2) Acid treatment of purified sepiolite
a. Mixing 5g of purified sepiolite with 100ml of hydrochloric acid with the mass fraction of 0.34mol/L, and standing for 48 hours;
b. after the completion of the standing, the supernatant was poured off, the lower layer was repeatedly washed with deionized water 3 times, and finally the pH was adjusted to neutral with NaOH.
c. And centrifugally separating the washed suspension to obtain acid-treated sepiolite precipitate, drying for 24 hours, and grinding to obtain the acid-treated sepiolite.
(3) Modification of acid treated and purified sepiolite manganese dioxide
A. Preparing 0.908g of potassium permanganate into 100mL of solution, adding the solution into 5g of HCl modified sepiolite, heating and stirring the solution in a constant-temperature water bath kettle at 100 ℃ for 30min, slowly dripping 1.92mL of concentrated hydrochloric acid after 30min, and finishing dripping within 30 min;
B. after the dropwise addition, the water bath heating and stirring state was maintained for 2 hours, and then the heating and stirring were stopped. Standing for layering, pouring out supernatant, repeatedly washing lower layer with deionized water for several times, drying in an oven at 80 deg.C for 12 hr, and grinding to obtain sample.
Firstly, preparing a series of Cd with different concentrations2+Is a solution, and the working solution is prepared by the method. Adding modified sepiolite into the solution, adjusting pH to 6, oscillating at constant temperature for 4 hr, centrifuging to obtain supernatant, and removing residual Cd2+The concentration is determined by an atomic absorption spectrophotometer according to Cd in the working solution before and after adsorption2+Calculating the concentration of the modified sepiolite to the heavy metal Cd2+The amount of adsorption of (3). The obtained solid adsorbent is used for Cd2+The adsorption capacity of the adsorbent is improved to 9.73mg/g from the original 6.26 mg/g.
Comparative example 4
Other conditions were the same as in example 1, only the pH of the adsorption experiment was adjusted to 2, and the specific experimental steps were as follows:
(1) purification of sepiolite (reference patent publication No. CN106745014A)
a. Weighing 20g of sepiolite raw ore, adding 400mL of deionized water, and stirring for 3h at normal temperature;
b. and after stirring, pouring the mixture into a separating funnel, standing for layering, taking the lower layer, adding water to 400mL, stirring for 1h, pouring the mixture into the separating funnel again, standing for layering, and repeating the steps for several times until the layering is avoided. 0.48g of sodium hexametaphosphate was added, and after stirring for 3 hours, the mixture was allowed to stand for 48 hours.
c. Taking the upper layer of the slurry after standing for 48 hours, centrifugally separating, drying in a drying oven at 108 ℃ for 24 hours, and grinding to obtain the purified sepiolite.
(2) Acid treatment of purified sepiolite
a. Mixing 5g of purified sepiolite with 100ml of hydrochloric acid with the mass fraction of 0.34mol/L, and standing for 48 hours;
b. after the standing is finished, pouring out the supernatant, and repeatedly washing the lower layer with deionized water for several times; finally, the pH is adjusted to be neutral by NaOH.
c. And centrifugally separating the washed suspension to obtain acid-treated sepiolite precipitate, drying for 24 hours, and grinding to obtain the acid-treated sepiolite.
(3) Modification of acid treated and purified sepiolite manganese dioxide
A. Preparing 100mL solution of 7.264g potassium permanganate into 5g HCl modified sepiolite, heating and stirring in a 100 ℃ constant temperature water bath kettle for 30min, slowly dripping 15.36mL concentrated hydrochloric acid after 30min, and finishing dripping within 30 min;
B. after the dropwise addition, the water bath heating and stirring state was maintained for 2 hours, and then the heating and stirring were stopped. Standing for layering, pouring out supernatant, repeatedly washing lower layer with deionized water for several times, drying in an oven at 80 deg.C for 12 hr, and grinding to obtain sample.
Firstly, preparing a series of Cd with different concentrations2+Is a solution, and the working solution is prepared by the method. Adding modified sepiolite into the solution, adjusting the mass-volume ratio of the modified sepiolite to the working solution to be 1:2g/L, adjusting the pH to be 2, carrying out constant-temperature oscillation adsorption for 4h, carrying out centrifugal separation to obtain supernatant, and carrying out centrifugal separation on residual Cd2+The concentration is determined by an atomic absorption spectrophotometer according to Cd in the working solution before and after adsorption2+Calculating the concentration of the modified sepiolite to the heavy metal Cd2+The amount of adsorption of (3). The obtained solid adsorbent is used for Cd2+The original 6.26mg/g of the adsorption capacity of the adsorbent is improved to 21.83 mg/g.
Comparative example 5
The other conditions are the same as the example 1, the acid solution is added at one time instead of dropwise adding only during the modification process of the manganese dioxide, and the specific experimental steps are as follows:
(1) purification of sepiolite (reference patent publication No. CN106745014A)
a. Weighing 20g of sepiolite raw ore, adding 400mL of deionized water, and stirring for 3h at normal temperature;
b. and after stirring, pouring the mixture into a separating funnel, standing for layering, taking the lower layer, adding water to 400mL, stirring for 1h, pouring the mixture into the separating funnel again, standing for layering, and repeating the steps for several times until the layering is avoided. 0.48g of sodium hexametaphosphate was added, and after stirring for 3 hours, the mixture was allowed to stand for 48 hours.
c. Taking the upper layer of the slurry after standing for 48 hours, centrifugally separating, drying in a drying oven at 108 ℃ for 24 hours, and grinding to obtain the purified sepiolite.
(2) Acid treatment of purified sepiolite
a. Mixing 5g of purified sepiolite with 100ml of hydrochloric acid with the mass fraction of 0.34mol/L, and standing for 48 hours;
b. after the standing is finished, pouring out the supernatant, and repeatedly washing the lower layer with deionized water for several times; finally, the pH is adjusted to be neutral by NaOH.
c. And centrifugally separating the washed suspension to obtain acid-treated sepiolite precipitate, drying for 24 hours, and grinding to obtain the acid-treated sepiolite.
(3) Modification of acid treated and purified sepiolite manganese dioxide
A. Preparing 100mL solution of 7.264g potassium permanganate into 5g HCl modified sepiolite, heating and stirring in a 100 ℃ constant temperature water bath kettle for 30min, and adding 15.36mL concentrated hydrochloric acid at one time;
B. after the dropwise addition, the water bath heating and stirring state was maintained for 2 hours, and then the heating and stirring were stopped. Standing for layering, pouring out supernatant, repeatedly washing lower layer with deionized water for several times, drying in an oven at 80 deg.C for 12 hr, and grinding to obtain sample.
Firstly, preparing a series of Cd with different concentrations2+Is a solution, and the working solution is prepared by the method. Adding modified sepiolite into the solution, adjusting pH to 6, oscillating at constant temperature for 4 hr, centrifuging to obtain supernatant, and removing residual Cd2+The concentration is determined by an atomic absorption spectrophotometer according to Cd in the working solution before and after adsorption2+Calculating the concentration of the modified sepiolite to the heavy metal Cd2+The amount of adsorption of (3). The obtained solid adsorbent is used for Cd2+The adsorption capacity of (2) was 9.26mg/g, and little improvement in adsorption performance was observed because the manganese dioxide was not completely supported on the sepiolite by adding concentrated hydrochloric acid at one time.

Claims (6)

1. A preparation method of manganese dioxide modified sepiolite adsorbent is characterized by comprising the following steps: adding acid-treated sepiolite into a potassium permanganate solution to obtain a mixed solution, heating, and dropwise adding hydrochloric acid into the mixed solution, wherein the liquid-solid volume mass ratio of the hydrochloric acid to the potassium permanganate is 2-2.5 ml:1 g, and the mass fraction of HCl dissolved in the hydrochloric acid is 20% -38%; the dropping speed is 0.15-0.8 ml/min; continuing the reaction after the dropwise adding, and carrying out solid-liquid separation to obtain a solid, namely the manganese dioxide modified sepiolite adsorbent;
the sepiolite is obtained by purifying raw sepiolite ore, and the preparation method of the acid-treated sepiolite comprises the following steps: mixing sepiolite with an acid solution B to obtain a suspension, standing, separating supernatant, washing the lower layer, performing solid-liquid separation, drying, grinding, sieving with a 120-mesh sieve, and taking undersize product to obtain acid-treated sepiolite; the standing time is 12-48 h; the liquid-solid volume mass ratio of the potassium permanganate solution to the acid-treated sepiolite is 10-30 ml:1 g; in the mixed solution, the mass ratio of the sepiolite subjected to acid treatment to the manganese element is as follows: 1.5-8: 1, the mass of manganese dioxide in the manganese dioxide modified sepiolite adsorbent is 40-80% of that of the sepiolite.
2. The preparation method of manganese dioxide modified sepiolite adsorbent according to claim 1, wherein: and heating and stirring the mixed solution at the temperature of 80-100 ℃ for 20-30 min, then dropwise adding the acid solution A into the mixed solution, and keeping the temperature of 80-100 ℃ in the dropwise adding process.
3. The preparation method of manganese dioxide modified sepiolite adsorbent according to claim 1, wherein: the reaction temperature is 80-100 ℃, and the reaction time is 2-3 h.
4. The preparation method of manganese dioxide modified sepiolite adsorbent according to claim 1, wherein:
h in the acid solution B+The concentration of (A) is 0.04-6 mol/L;
the acid solution B is at least one selected from hydrochloric acid, sulfuric acid and nitric acid;
the mass ratio of the sepiolite to the acid solution B is 1: 5-30.
5. The application of the manganese dioxide modified sepiolite adsorbent obtained by the preparation method according to any one of claims 1 to 4 in adsorbing metal ions in an aqueous solution.
6. The manganese dioxide modified sepiolite adsorbent obtained by the preparation method according to any one of claims 1 to 4, which is used for adsorbing Cd in an aqueous solution2+The use of (1).
CN201810561633.8A 2018-06-04 2018-06-04 Preparation method and application of manganese dioxide modified sepiolite adsorbent Active CN108905954B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201810561633.8A CN108905954B (en) 2018-06-04 2018-06-04 Preparation method and application of manganese dioxide modified sepiolite adsorbent

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201810561633.8A CN108905954B (en) 2018-06-04 2018-06-04 Preparation method and application of manganese dioxide modified sepiolite adsorbent

Publications (2)

Publication Number Publication Date
CN108905954A CN108905954A (en) 2018-11-30
CN108905954B true CN108905954B (en) 2021-09-10

Family

ID=64419506

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201810561633.8A Active CN108905954B (en) 2018-06-04 2018-06-04 Preparation method and application of manganese dioxide modified sepiolite adsorbent

Country Status (1)

Country Link
CN (1) CN108905954B (en)

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110205132A (en) * 2019-05-28 2019-09-06 安徽大学 A kind of preparation method and application of PERFORMANCE OF MODIFIED VERMICULITE-montmorillonite composite material
CN110575812B (en) * 2019-09-25 2022-03-22 西南石油大学 Environment-friendly adsorbing material for efficient phosphorus removal of argil/pyrolusite and preparation method thereof
CN111170501B (en) * 2019-12-30 2022-05-24 安徽得奇环保科技股份有限公司 Method for treating nickel-containing wastewater by using composite adsorbent
CN111573882A (en) * 2020-04-16 2020-08-25 中南大学 Process for deeply removing heavy metals in water body
CN112121757A (en) * 2020-09-07 2020-12-25 湘潭大学 Preparation method and application of magnesium oxide modified sepiolite adsorbent
CN112058232B (en) * 2020-09-21 2021-10-22 河南大学 Manganese dioxide modified activated carbon composite adsorbent, preparation method thereof and application thereof in arsenic removal
CN112429793A (en) * 2020-11-24 2021-03-02 北京华德创业环保设备有限公司 Desulfurization wastewater treatment integrated agent and preparation method thereof
CN112774620A (en) * 2021-01-29 2021-05-11 赵慧鸣 Modified vermiculite/manganese dioxide for Pb (II) wastewater treatment and preparation method thereof
CN115090256B (en) * 2022-06-22 2023-08-18 兰州理工大学 Sodium-sulfate modified sepiolite and modification method and application thereof

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0829299A4 (en) * 1995-05-26 1999-02-10 Hitachi Chemical Co Ltd Environment purifying material
CN102614827A (en) * 2012-04-20 2012-08-01 哈尔滨工业大学 Preparation method of modified sepiolite supported nano iron material
CN103041787B (en) * 2013-01-08 2014-08-13 山东大学 Preparation method of crosslinked chitosan-manganese dioxide composite adsorbing material
CN107344093A (en) * 2017-05-09 2017-11-14 湘潭海泡石科技有限公司 A kind of sepiolite/TiO of the strong absorption property of multi-channel structure2Composite and preparation method thereof

Also Published As

Publication number Publication date
CN108905954A (en) 2018-11-30

Similar Documents

Publication Publication Date Title
CN108905954B (en) Preparation method and application of manganese dioxide modified sepiolite adsorbent
CN109569545B (en) Method for preparing aluminum-silicon porous material from fly ash
CN107321335B (en) Preparation method and application method of adsorbent for treating reactive dye wastewater
CN112316924B (en) Gangue-based porous composite material and preparation method and application thereof
CN111701578A (en) Adsorbent for sewage treatment and preparation method thereof
CN109012565A (en) A kind of method of the magnetic carbon material Adsorption heavy metal ions in wastewater of nitrating
CN102580743A (en) Method for preparing oxidation catalyst from gold ore tailing slag, and prepared oxidation catalyst and application thereof
EP2557067B1 (en) Method for preparing manganese sulfate monohydrate
CN110813241A (en) Nitrogen-oxygen co-doped porous carbon material and preparation method and application thereof
CN110294473B (en) Preparation process for purifying microcrystalline graphite by organic acid catalysis
CN102092754B (en) Method for removing impurity iron in aluminum sulfate solution through ion exchange
CN116835734A (en) Desulfurization wastewater integrated efficient flocculation medicament and preparation method thereof
CN112121757A (en) Preparation method and application of magnesium oxide modified sepiolite adsorbent
CN110665468B (en) Preparation method of adsorbent for industrial wastewater treatment
CN117339551A (en) Composite material synthesis method with reduction and adsorption effects on tellurium
CN110624517B (en) Nano hollow polyaniline and preparation method and application thereof
CN114887587B (en) Porous adsorbent for heavy metals in wastewater prepared from lithium mine waste residues as raw materials and preparation method thereof
CN110833816A (en) Preparation method of dipotassium hydrogen phosphate modified enteromorpha biological carbon and application of dipotassium hydrogen phosphate modified enteromorpha biological carbon in removing heavy metal cadmium in water body
CN107930576B (en) Preparation method of fly ash microbead porous material and prepared porous material
GB2622157A (en) Wastewater adsorbent, and preparation method therefor and use thereof
CN109482133B (en) Method for preparing adsorbing material by using waste liquid of Hummers method
CN106396050A (en) A method of preparing a poly-aluminum-ferric-silicate water purifier
CN113087207A (en) Method for purifying non-ferrous metal beneficiation wastewater based on porous magnesium oxide cyclic preparation
CN112250090A (en) Production method for deeply removing fluorine in lithium sulfate solution
CN108993387A (en) A kind of method of contents of many kinds of heavy metal ion in the carbon-based magnetic material Adsorption waste water of fluorine doped

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant