CN113003764A - Method for removing arsenic in contaminated acid by taking siderite as in-situ iron source - Google Patents

Method for removing arsenic in contaminated acid by taking siderite as in-situ iron source Download PDF

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CN113003764A
CN113003764A CN202110186839.9A CN202110186839A CN113003764A CN 113003764 A CN113003764 A CN 113003764A CN 202110186839 A CN202110186839 A CN 202110186839A CN 113003764 A CN113003764 A CN 113003764A
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arsenic
filtrate
siderite
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acid
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王少锋
苏瑞
马旭
贾永锋
林金如
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Institute of Applied Ecology of CAS
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    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
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    • C02F9/00—Multistage treatment of water, waste water or sewage
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    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B30/00—Obtaining antimony, arsenic or bismuth
    • C22B30/04—Obtaining arsenic
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    • C22B7/00—Working up raw materials other than ores, e.g. scrap, to produce non-ferrous metals and compounds thereof; Methods of a general interest or applied to the winning of more than two metals
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    • C02F1/72—Treatment of water, waste water, or sewage by oxidation
    • C02F1/722—Oxidation by peroxides
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    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/72—Treatment of water, waste water, or sewage by oxidation
    • C02F1/727—Treatment of water, waste water, or sewage by oxidation using pure oxygen or oxygen rich gas
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
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    • C02F1/72—Treatment of water, waste water, or sewage by oxidation
    • C02F1/76—Treatment of water, waste water, or sewage by oxidation with halogens or compounds of halogens
    • 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
    • C02F2101/103—Arsenic compounds
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
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Abstract

The invention belongs to the technical field of dangerous solid waste treatment, and particularly relates to a method for removing arsenic in contaminated acid by taking siderite as an in-situ iron source. The invention provides a method for removing arsenic in contaminated acid by taking siderite as an in-situ iron source, which comprises the following steps: mixing the waste acid with a calcium hydroxide solution, and performing neutralization reaction to obtain calcium sulfate and trivalent arsenic filtrate; mixing the trivalent arsenic filtrate with hydrogen peroxide, and carrying out oxidation reaction to obtain pentavalent arsenic filtrate; and introducing oxygen-containing gas into the mixed solution of the pentavalent arsenic filtrate and the siderite to perform dearsenification reaction to obtain scorodite and dearsenification filtrate. According to the method provided by the invention, the scorodite prepared from the low-cost natural ore siderite is used for efficiently removing arsenic in the waste acid, and the calcium sulfate obtained by the neutralization reaction of the waste acid is low in arsenic content and can be recycled; the iron source is low in cost and easy to obtain, and the cost in the waste acid treatment process can be obviously reduced; the arsenic removal efficiency is high, and the generated scorodite arsenic has high stability.

Description

Method for removing arsenic in contaminated acid by taking siderite as in-situ iron source
Technical Field
The invention belongs to the technical field of dangerous solid waste treatment, and particularly relates to a method for removing arsenic in contaminated acid by taking siderite as an in-situ iron source.
Background
The most common iron-containing minerals found in nature are mainly siderite, which is an iron carbonate ore. The main phase of the siderite is FeCO3The FeO content was 62.01%, CO2The content was 37.99%. The siderite resource in China is very rich, the cost is low and the siderite resource is easy to obtain.
In the production process of nonferrous smelting zinc, smelting flue gas generated in a sulfuric acid workshop is washed to generate a large amount of high-arsenic-content waste water called waste acid, the arsenic content of the waste acid is 0.5-15 g/L, the sulfuric acid content of the waste acid is 3-20%, and the waste acid waste water can be discharged through a treatment method so as to meet the requirement of environmental protection.
At present, the waste acid treatment methods which are widely applied are a lime neutralization precipitation method, a neutralization iron salt method and a vulcanization method. However, the methods all have the following defects: (1) although the lime neutralization precipitation method has simple process and low disposal cost, the product is arsenic-calcium slag which is unstable in the environment and belongs to secondary hazardous waste; (2) although the iron salt neutralization method is stable, the consumption of iron salt is large, the slag amount is large, multi-stage treatment is needed, and a large amount of waste slag is generated to cause difficulty in landfill; (3) although the sulfuration method has high arsenic removal rate and small slag yield, the generated arsenic sulfide is unstable and the treatment cost is expensive, so that the method is difficult to bear by common enterprises.
Disclosure of Invention
In view of the above, the invention provides a method for removing arsenic in contaminated acid by using siderite as an in-situ iron source, and the method provided by the invention has the advantages that the siderite is used as an in-situ iron source for removing arsenic, the removal rate of arsenic elements is high and stable, and the production cost is low.
The invention provides a method for removing arsenic in contaminated acid by taking siderite as an in-situ iron source, which comprises the following steps:
mixing calcium hydroxide or calcium oxide with a waste acid solution, and performing neutralization reaction to obtain calcium sulfate and trivalent arsenic filtrate;
mixing the trivalent arsenic filtrate with an oxidant, and carrying out oxidation reaction to obtain pentavalent arsenic filtrate;
and introducing oxygen-containing gas into the mixed solution of the pentavalent arsenic filtrate and the siderite to perform dearsenification reaction to obtain scorodite and dearsenification filtrate.
Preferably, the pH value of the trivalent arsenic filtrate is 0.7-2.0;
the dosage of the calcium hydroxide or the calcium oxide is based on the trivalent arsenic filtrate with the pH value of 0.7-2.0.
Preferably, the mass ratio of the oxidant to the arsenic element in the waste acid is (1.0-2.0): 1.
preferably, the oxidant comprises hydrogen peroxide, potassium permanganate or perchloric acid.
Preferably, the temperature of the oxidation reaction is room temperature, and the time of the oxidation reaction is 40-60 min;
the oxidation reaction is carried out under the condition of stirring, and the stirring speed is 180-200 r/min.
Preferably, the mass ratio of the iron element in the siderite to the arsenic element in the contaminated acid is (0.7-2.0): 1.
Preferably, the flow ratio of the volume of the waste acid to the oxygen-containing gas is (2-3) L: 1L/min;
the oxygen-containing gas is air or oxygen.
Preferably, the temperature of the dearsenification reaction is 65-95 ℃, and the time is 2-12 h;
the dearsenization reaction is carried out under the condition of stirring, and the stirring speed is 220-250 r/min.
Preferably, the concentration of arsenic element in the waste acid is 5.7-24.6 g/L; the concentration of the sulfuric acid is 68-290 g/L.
Preferably, after calcium sulfate is obtained, the calcium sulfate is washed, the washed solvent is an acidified saturated gypsum solution, the pH value of the acidified saturated gypsum solution is 1-3, and the washing times are 6-8.
The invention provides a method for removing arsenic in contaminated acid by taking siderite as an in-situ iron source, which comprises the following steps: mixing calcium hydroxide or calcium oxide with a waste acid solution, and performing neutralization reaction to obtain calcium sulfate and trivalent arsenic filtrate; mixing the trivalent arsenic filtrate with an oxidant, and carrying out oxidation reaction to obtain pentavalent arsenic filtrate; and introducing oxygen-containing gas into the mixed solution of the pentavalent arsenic filtrate and the siderite to perform dearsenification reaction to obtain scorodite and dearsenification filtrate. According to the method provided by the invention, calcium sulfate by-products and trivalent arsenic filtrate are obtained by mixing the calcium sulfate with calcium hydroxide or calcium oxide with the waste acid solution for neutralization reaction, so that the concentration of sulfate radicals in the waste acid is reduced, and the sulfate radical range required by the synthesis of scorodite through dearsenification reaction is met; and then mixing the trivalent arsenic filtrate with an oxidant for oxidation reaction to obtain pentavalent arsenic filtrate, introducing oxygen-containing gas into the mixed solution of the pentavalent arsenic filtrate and the siderite for dearsenification reaction, and performing redox reaction by using ferrous carbonate, the oxygen and the pentavalent arsenic in the siderite to generate scorodite dearsenification. According to the method provided by the invention, the scorodite is prepared by using the low-cost natural ore siderite, the arsenic in the waste acid is efficiently removed, and the calcium sulfate obtained by the neutralization reaction of the waste acid has low arsenic content and can be recycled; the iron source is low in cost and easy to obtain, and the cost in the waste acid treatment process can be obviously reduced; the arsenic removal efficiency is high, and the generated scorodite arsenic has high stability. The results of the embodiment show that the arsenic removal rate of the Method provided by the invention is 99.91-99.99%, and the leaching concentration of scorodite arsenic is lower than that of Method 1311 issued by the environmental protection agency of the United states of 1992: the standard of the Toxicity test of the Toxicity Characteristic Leaching Procedure can be stored safely for a long time, and the arsenic content in the arsenic-removed filtrate is 0.81-3.30 mg/L.
The treatment method provided by the invention has the advantages of simple process operation, low cost of calcium hydroxide or calcium oxide and siderite, low iron ion consumption, high arsenic removal efficiency, low energy consumption, high stability, capability of recovering calcium sulfate and wide market prospect.
Drawings
FIG. 1 is a process flow diagram provided in example 1 of the present invention;
FIG. 2 is an XRD pattern of calcium sulfate prepared according to example 1 of the present invention;
FIG. 3 is an SEM-EDS picture of calcium sulfate prepared in example 1 of the present invention;
FIG. 4 is an XRD pattern of scorodite prepared according to example 1 of the present invention;
FIG. 5 is an SEM photograph of scorodite prepared in example 1 of the present invention;
FIG. 6 is an XRD pattern of scorodite prepared in example 2 of the present invention;
FIG. 7 is an SEM photograph of scorodite prepared in example 2 of the present invention;
FIG. 8 is an XRD pattern of scorodite prepared according to example 3 of the present invention;
FIG. 9 is an SEM photograph of scorodite prepared in example 3 of the present invention;
FIG. 10 is an SEM image of scorodite prepared in comparative example 1 of the present invention;
FIG. 11 is an SEM image of scorodite prepared in comparative example 2 of the present invention;
fig. 12 is an SEM image of scorodite prepared in comparative example 3 of the present invention.
Detailed Description
The invention provides a method for removing arsenic in contaminated acid by taking siderite as an in-situ iron source, which comprises the following steps:
mixing calcium hydroxide or calcium oxide with a waste acid solution, and performing neutralization reaction to obtain calcium sulfate and trivalent arsenic filtrate;
mixing the trivalent arsenic filtrate with an oxidant, and carrying out oxidation reaction to obtain pentavalent arsenic filtrate;
and introducing oxygen-containing gas into the mixed solution of the pentavalent arsenic filtrate and the siderite to perform dearsenification reaction to obtain scorodite and dearsenification filtrate.
In the present invention, the starting materials are all commercially available products well known to those skilled in the art, unless otherwise specified.
The method mixes the calcium hydroxide and the waste acid solution for neutralization reaction to obtain the calcium sulfate and trivalent arsenic filtrate.
In the invention, the concentration of arsenic element in the waste acid is preferably 5.7-24.6 g/L; the concentration of the sulfuric acid is preferably 68-290 g/L. In the invention, the waste acid is a large amount of high arsenic-containing wastewater generated after the smelting flue gas generated in a sulfuric acid workshop is washed in the production process of nonferrous smelting zinc.
In the present invention, the calcium hydroxide is preferably a calcium hydroxide solution; the molar concentration of the calcium hydroxide solution is preferably (1-6) mol/L, and more preferably 2-3 mol/L; in the present invention, the amount of the calcium hydroxide solution is preferably based on the pH of the obtained trivalent arsenic solution. In the invention, the pH value of the trivalent arsenic filtrate is preferably 0.7-2.0, and more preferably 1.0-1.3;
the invention has no special requirements for the specific implementation mode of mixing the calcium hydroxide or calcium oxide with the waste acid solution, and in the specific implementation mode of the invention, the mixing is preferably as follows: the calcium hydroxide or calcium oxide solution is added into the waste acid in batches, and the invention has no special requirement on the number of the added batches. In the present invention, the mixing is preferably carried out under stirring conditions, and the stirring speed is preferably the same as that of the neutralization reaction.
In the invention, the neutralization reaction is the neutralization reaction of calcium hydroxide or calcium oxide and sulfuric acid in waste acid to generate calcium sulfate. In the invention, the neutralization reaction is preferably carried out under the condition of stirring, the stirring speed is preferably 180-200 r/min, and the invention has no special requirements on the specific implementation process of the stirring.
In the invention, after the neutralization reaction is finished, solid-liquid separation is preferably carried out on the neutralization reaction liquid to obtain calcium sulfate and trivalent arsenic filtrate. According to the invention, the calcium sulfate is preferably washed, the solvent for washing is preferably an acidified saturated gypsum solution, the pH of the acidified saturated gypsum solution is preferably 1-3, more preferably 1.1-1.3, and the number of washing is preferably 6-8, more preferably 7. The invention provides the purity of the calcium sulfate by washing.
After the trivalent arsenic filtrate is obtained, the invention mixes the trivalent arsenic filtrate with an oxidant to carry out oxidation reaction, and then pentavalent arsenic filtrate is obtained.
In the invention, the oxidant preferably comprises hydrogen peroxide, potassium permanganate or perchloric acid; more preferably hydrogen peroxide; in the present invention, the ratio of the amounts of the oxidizing agent and the arsenic in the contaminated acid is preferably (1.0 to 2.0):1, more preferably (1.1 to 1.5): 1; in the invention, the mass concentration of the hydrogen peroxide is preferably 27.5% or 30%, more preferably 30%, and the mass concentration of the perchloric acid is preferably 70-72%; the potassium permanganate is preferably a potassium permanganate solution; the invention has no special requirement on the mass concentration of the potassium permanganate solution.
The invention has no special requirements on the specific implementation process of mixing the trivalent arsenic filtrate and the oxidant, and in the invention, when an experimental laboratory experiment is carried out, the oxidant is preferably dropwise added into the trivalent arsenic filtrate, and the dropwise adding speed and the volume ratio of the trivalent arsenic filtrate are preferably 1-5 mL/min: 250 mL; in the invention, when an industrial production experiment is carried out, the mixing is preferably carried out by adding the hydrogen peroxide water into the trivalent arsenic filtrate in batches, and the number of the batches and the volume ratio of the trivalent arsenic filtrate are preferably (10-20): 1L of the compound. In the present invention, the mixing is preferably performed under a halving condition, and the stirring speed is preferably the same as that of the oxidation reaction.
In the invention, the temperature of the oxidation reaction is preferably room temperature, and the time of the oxidation reaction is preferably 40-60 min, and more preferably 45-55 min; in the invention, the oxidation reaction is preferably carried out under the condition of stirring, the stirring speed is preferably 180-200 r/min, and the invention has no special requirements on the specific implementation process of the stirring.
The invention oxidizes trivalent arsenic into pentavalent arsenic through oxidation reaction.
After pentavalent arsenic filtrate is obtained, the invention introduces oxygen-containing gas into the mixed solution of the pentavalent arsenic filtrate and siderite to carry out dearsenification reaction, thus obtaining scorodite and dearsenification filtrate.
Before the dearsenification reaction is carried out, the siderite is preferably subjected to pretreatment, in the invention, the pretreatment preferably comprises crushing and grinding in sequence, the crushing and grinding are not particularly required to be carried out in the invention, and the operation well known by the technical personnel in the field can be adopted, and in the invention, the siderite is preferably less than or equal to 10 microns, more preferably less than or equal to 5 microns in particle size after the pretreatment.
In the invention, the ratio of the amount of iron in the siderite to the amount of arsenic in the contaminated acid is preferably (0.7-2.0): 1, more preferably (1.5-2.0): 1; the volume of the waste acid and the flow ratio of the oxygen-containing gas are preferably (2-3) L: 1L/min, more preferably 2.5L: 1L/min; in the present invention, the oxygen-containing gas is preferably air or oxygen, more preferably air.
The pentavalent arsenic filtrate is mixed with siderite to obtain a mixed solution. In the present invention, the mixing is preferably performed under the condition of stirring at the same speed as the dearsenification reaction.
In the invention, the temperature of the dearsenification reaction is preferably 65-95 ℃, more preferably 70-90 ℃, and the time of the dearsenification reaction is preferably 2-12 h, more preferably 6-10 h; in the invention, the dearsenization reaction is preferably carried out under the condition of stirring, and the stirring speed is preferably 220-250 r/min, and more preferably 230-240 r/min. The invention has no special requirements on the specific implementation process of the stirring.
After the arsenic removal reaction is completed, the invention preferably performs post-treatment on the arsenic removal reaction liquid to obtain scorodite and arsenic removal filtrate, and in the invention, the post-treatment preferably comprises solid-liquid separation.
In the present invention, the formula of the dearsenification reaction is shown as formula I:
4FeCO3+4H3AsO4+2H2O+O2(g)＝4FeAsO4·2H2O+4CO2(g) formula I;
in the invention, the siderite and the pentavalent arsenic filtrate are subjected to dearsenification reaction, the obtained scorodite has stable performance, the stable fixation of arsenic element can be realized, and undissolved siderite and iron oxide in other forms formed by siderite at high temperature can also play a role in physically adsorbing the arsenic element, thereby further improving the removal rate of arsenic in the contaminated acid.
In order to further illustrate the present invention, the method for harmlessly treating arsenic alkali residue provided by the present invention will be described in detail with reference to the following examples, which should not be construed as limiting the scope of the present invention.
Example 1
According to the process flow shown in fig. 1, the siderite in the embodiment has the components shown in table 1, the waste acid is obtained from a sulfuric acid workshop of a certain zinc smelting plant in Henan province and is generated after the smelting flue gas is washed, and the main components are shown in table 2;
TABLE 1 siderite component (% by mass)
Fe K Ca O
38 1.3 1.4 Balance
TABLE 2 dirty acid composition (mg/L)
As(III) As(T) H2SO4 Cu Zn Pb Cd
5600 5700 67000 40 100 100 1800
Dropwise adding 1mol/L calcium hydroxide solution into 250mL of waste acid, performing neutralization reaction under the stirring condition of 180r/min, measuring the pH value of the reaction solution, stopping dropwise adding when the pH value of the reaction solution is 1.1, completing the neutralization reaction, performing solid-liquid separation to obtain calcium sulfate and trivalent arsenic filtrate, and washing the calcium sulfate for 7 times by using acid saturated gypsum solution with the pH value of 1.1 to obtain high-purity calcium sulfate; the arsenic content in the high-purity calcium sulfate is 71 mg/kg;
dropwise adding hydrogen peroxide into the trivalent arsenic filtrate by using a peristaltic pump, wherein the concentration of the hydrogen peroxide is 30 percent, and H in the hydrogen peroxide2O2Performing oxidation reaction with arsenic in the waste acid at a stirring speed of 180r/min at a ratio of 1.1:1, wherein the reaction time is 40min and the temperature is room temperature to obtain pentavalent arsenic filtrate;
crushing and grinding siderite to obtain siderite powder with the particle size of 10 mu m, mixing the siderite powder with pentavalent arsenic filtrate according to the mass ratio of iron element in the siderite powder to arsenic element in the pentavalent arsenic filtrate of 2.0:1 to obtain a mixed solution, introducing oxygen into the mixed solution, wherein the flow of the oxygen is 0.1L/min, carrying out elaborate dearsenification reaction under the shift condition that the halving speed is 250r/min, the reaction temperature is 90 ℃, the reaction time is 10 hours, and carrying out solid-liquid separation after the reaction is finished to obtain scorodite and dearsenification filtrate, wherein the concentration of arsenic in the dearsenification filtrate is 0.8mg/L, and the removal rate of arsenic is 99.99%;
the toxicity Leaching test of the scorodite is carried out according to the Method of U.S. EPA (Method 1311-toxicityCharactericitic Leaching Procedure), the Leaching concentration of As in the filtrate is determined to be 0.19mg/L, and the scorodite has higher environmental stability and can be stored safely.
Fig. 2 is an XRD pattern of calcium sulfate prepared in example 1 of the present invention, and it can be seen from fig. 2 that calcium sulfate prepared in this example has high crystallinity, few peaks in the crystal, and high purity.
Fig. 3 is an SEM-EDS of the calcium sulfate prepared in example 1 of the present invention, and it can be seen from fig. 3 that the calcium sulfate prepared in this example has a complete crystal shape, a rectangular parallelepiped shape, and a uniform particle size distribution.
Fig. 4 is an XRD chart of the scorodite prepared in example 1 of the present invention, and as can be seen from fig. 4, the scorodite prepared in this example has high crystallinity, undissolved siderite in the crystal, few miscellaneous peaks and high purity.
Fig. 5 is an SEM image of scorodite prepared in example 1 of the present invention, and it can be seen from fig. 5 that scorodite prepared in this example has complete crystal morphology, is spherical, and has uniform particle size distribution.
Example 2
The method according to embodiment 1 differs in that: introducing air, keeping the rest reaction conditions unchanged, wherein the concentration of arsenic in the arsenic-removed filtrate is 1.01mg/L, and the removal rate of arsenic is 99.98%; the arsenic content in the high-purity calcium sulfate is 71 mg/kg.
The toxicity Leaching test of the arsenic-containing solid is carried out according to the Method of U.S. EPA (Method 1311-toxicityCharactericitic Leaching Procedure) provided by the United states environmental protection agency, and the Leaching concentration of As in the filtrate is determined to be 0.30mg/L, so that the arsenic-containing solid has higher environmental stability and can be safely stored.
Fig. 6 is an XRD chart of the scorodite prepared in example 2 of the present invention, and it can be seen from fig. 6 that the scorodite prepared in this example has high crystallinity, and undissolved siderite, few impurities and high purity are also present in the crystal.
Fig. 7 is an SEM image of scorodite prepared in example 2 of the present invention, and it can be seen from fig. 7 that scorodite prepared in this example has complete crystal morphology, is also spherical, and has uniform particle size distribution.
Example 3
The contaminated acid obtained from the sulfuric acid plant of another zinc smelting plant in Henan province was treated in the same manner as in example 1, with the main components shown in Table 3. The arsenic content in the obtained calcium sulfate is 71mg/kg, the arsenic concentration in the arsenic-removing filtrate is 1.61mg/L, and the arsenic removal rate is 99.99%.
The toxicity Leaching test of the arsenic-containing solid is carried out according to the Method of U.S. EPA (Method 1311-toxicityCharactericitic Leaching Procedure) provided by the United states environmental protection agency, and the Leaching concentration of As in the filtrate is determined to be 0.77mg/L, so that the arsenic-containing solid has higher environmental stability and can be safely stored.
TABLE 3 dirty acid composition (mg/L)
Figure BDA0002943366090000081
Fig. 8 is an XRD chart of the scorodite prepared in example 3 of the present invention, and as can be seen from fig. 8, the scorodite prepared in this example has high crystallinity, and also undissolved siderite in the crystal, few miscellaneous peaks and high purity.
Fig. 9 is an SEM image of scorodite prepared in example 3 of the present invention, and it can be seen from fig. 9 that scorodite prepared in this example has complete crystal morphology, is also spherical, and has uniform particle size distribution.
Example 4
The contaminated acid was obtained from a sulfuric acid plant of zinc smeltery in Hunan province, and the main components of the contaminated acid produced by washing the smelting flue gas were treated according to the method of example 1, as shown in Table 4. The arsenic content in the obtained calcium sulfate is 81mg/kg, the arsenic concentration in the arsenic-removing filtrate is 2.26mg/L, and the arsenic removal rate is 99.91%.
The toxicity Leaching test of the arsenic-containing solid is carried out according to the Method of U.S. EPA (Method 1311-toxicityCharactericitic Leaching Procedure) provided by the United states environmental protection agency, and the Leaching concentration of As in the filtrate is determined to be 2.18mg/L, so that the arsenic-containing solid has higher environmental stability and can be safely stored.
TABLE 4 dirty acid composition (mg/L)
Figure BDA0002943366090000091
Example 5
The method according to embodiment 1 differs in that: adding siderite with the quantity ratio of iron to arsenic substances of 1.5:1, keeping the rest reaction conditions unchanged, wherein the concentration of arsenic in the arsenic-removed filtrate is 3.30mg/L, and the removal rate of arsenic is 99.94%; the arsenic content in the high-purity calcium sulfate is 71 mg/kg.
The toxicity Leaching test of the arsenic-containing solid is carried out according to the Method of U.S. EPA (Method 1311-toxicityCharactericitic Leaching Procedure) provided by the United states environmental protection agency, and the Leaching concentration of As in the filtrate is determined to be 0.21mg/L, so that the arsenic-containing solid has higher environmental stability and can be safely stored.
Example 6
The method according to embodiment 1 differs in that: the reaction temperature is 85 ℃, the rest reaction conditions are unchanged, the concentration of arsenic in the arsenic-removing filtrate is 0.84mg/L, and the removal rate of arsenic is 99.99 percent; the arsenic content in the high-purity calcium sulfate is 71 mg/kg.
The toxicity Leaching test of the arsenic-containing solid is carried out according to the Method of U.S. EPA (Method 1311-toxicityCharactericitic Leaching Procedure) provided by the United states environmental protection agency, and the Leaching concentration of As in the filtrate is determined to be 0.34mg/L, so that the arsenic-containing solid has higher environmental stability and can be safely stored.
Comparative example 1
The method according to embodiment 1 differs in that: siderite with the iron-arsenic molar ratio of 0.7:1 is added, the rest reaction conditions are unchanged, the concentration of arsenic in the arsenic-removed filtrate is 2385mg/L, the removal rate of arsenic is 58.15%, and the removal rate of arsenic is lower.
The toxicity Leaching test of arsenic-containing solids was carried out according to U.S. epa Method 1311-toxicitycharateristic Leaching Procedure provided by the united states environmental protection agency, and the Leaching concentration of As in the filtrate was determined to be 3.53mg/L, although meeting the standard, the Leaching concentration was too high.
Fig. 10 is an SEM image of scorodite prepared in comparative example 1 of the present invention, and it can be seen from fig. 10 that scorodite prepared in comparative example 1 has an incomplete crystal morphology, is in a cotton ball shape, and has a non-uniform particle size distribution.
Comparative example 2
According to the method of embodiment 1, the difference is that the reaction temperature is 65 ℃, the rest reaction conditions are unchanged, the concentration of arsenic in the filtrate is 2750mg/L, the removal rate of arsenic is 51.76%, and the removal rate of arsenic is lower.
The toxicity Leaching test of arsenic-containing solids was carried out according to U.S. epa Method 1311-toxicitycharateristic Leaching Procedure provided by the united states environmental protection agency, and the Leaching concentration of As in the filtrate was determined to be 3.13mg/L, although meeting the standard, the Leaching concentration was high.
Fig. 11 is an SEM image of scorodite prepared in comparative example 2 of the present invention, and it can be seen from fig. 11 that scorodite prepared in comparative example 2 has an incomplete crystal morphology, is in a cotton ball shape, and has a non-uniform particle size distribution.
Comparative example 3
According to the method of embodiment 1, the pH of the contaminated acid after the difference pretreatment is 2, the rest reaction conditions are unchanged, the concentration of arsenic in the arsenic-removed filtrate is 3255mg/L, the removal rate of arsenic is 42.90%, and the removal rate of arsenic is low.
The toxicity Leaching test of the arsenic-containing solid is carried out according to the Method of U.S. EPA (Method 1311-toxicityCharactericitic Leaching Procedure) provided by the United states environmental protection agency, and the Leaching concentration of As in the filtrate is determined to be 276mg/L, which does not meet the standard and has larger environmental risk.
Fig. 12 is an SEM image of scorodite prepared in comparative example 3 according to the present invention, and it can be seen from fig. 12 that scorodite prepared in comparative example 3 has an incomplete crystal morphology, is in a cotton ball shape, and has a non-uniform particle size distribution.
Although the present invention has been described in detail with reference to the above embodiments, it is only a part of the embodiments of the present invention, not all of the embodiments, and other embodiments can be obtained without inventive step according to the embodiments, and the embodiments are within the scope of the present invention.

Claims (10)

1. A method for removing arsenic in contaminated acid by taking siderite as an in-situ iron source is characterized by comprising the following steps:
mixing calcium hydroxide or calcium oxide with a waste acid solution, and performing neutralization reaction to obtain calcium sulfate and trivalent arsenic filtrate;
mixing the trivalent arsenic filtrate with an oxidant, and carrying out oxidation reaction to obtain pentavalent arsenic filtrate;
and introducing oxygen-containing gas into the mixed solution of the pentavalent arsenic filtrate and the siderite to perform dearsenification reaction to obtain scorodite and dearsenification filtrate.
2. The method according to claim 1, wherein the pH value of the trivalent arsenic filtrate is 0.7-2.0;
the dosage of the calcium hydroxide or the calcium oxide is based on the trivalent arsenic filtrate with the pH value of 0.7-2.0.
3. The method of claim 1, wherein the ratio of the amount of the substance of arsenic in the oxidizing agent to the amount of the substance of arsenic in the contaminated acid is (1.0 to 2.0): 1.
4. a method according to claim 1 or 3, wherein the oxidant comprises hydrogen peroxide, potassium permanganate or perchloric acid.
5. The method according to claim 1, wherein the temperature of the oxidation reaction is room temperature, and the time of the oxidation reaction is 40-60 min;
the oxidation reaction is carried out under the condition of stirring, and the stirring speed is 180-200 r/min.
6. The method according to claim 1, wherein the ratio of the amount of iron in the siderite to the amount of arsenic in the contaminated acid is (0.7-2.0): 1.
7. The method according to claim 1 or 6, wherein the flow ratio of the volume of the waste acid to the oxygen-containing gas is (2-3) L: 1L/min;
the oxygen-containing gas is air or oxygen.
8. The method according to claim 1, wherein the temperature of the dearsenification reaction is 65-95 ℃ and the time is 2-12 h;
the dearsenization reaction is carried out under the condition of stirring, and the stirring speed is 220-250 r/min.
9. The method according to claim 1, wherein the concentration of arsenic in the contaminated acid is 5.7-24.6 g/L; the concentration of the sulfuric acid is 68-290 g/L.
10. The method of claim 1, after obtaining the calcium sulfate, further comprising: and washing the calcium sulfate, wherein the washed solvent is an acidified saturated gypsum solution, the pH value of the acidified saturated gypsum solution is 1-3, and the washing times are 6-8.
CN202110186839.9A 2021-02-18 2021-02-18 Method for removing arsenic in contaminated acid by taking siderite as in-situ iron source Pending CN113003764A (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114314927A (en) * 2022-01-05 2022-04-12 大连理工大学 Co-treatment method for arsenic-containing waste acid and iron and arsenic waste residues
CN114573149A (en) * 2022-04-02 2022-06-03 中国科学院沈阳应用生态研究所 Co-treatment method for arsenic-containing waste acid and arsenic-calcium-containing waste residue
CN117797764A (en) * 2024-02-28 2024-04-02 广东顺控自华科技有限公司 Calcium-based siderite and preparation method and application thereof

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101830583A (en) * 2010-03-25 2010-09-15 云南铜业股份有限公司 Method for treating waste acid by gypsum sedimentation, arsenic oxidizing sedimentation and iron salt neutralization and co-precipitation
US20120164041A1 (en) * 2010-12-27 2012-06-28 Altynalmas Gold Ltd., a Canada Corporation Stabilization of Arsenic-Containing Wastes Generated During Treatment of Sulfide Ores
CN105753218A (en) * 2016-04-13 2016-07-13 中国科学院过程工程研究所 Method for removing trivalent arsenic
CN107739841A (en) * 2017-10-25 2018-02-27 湖南水口山有色金属集团有限公司 A kind of method for separating arsenic from containing the high copper dross slag of arsenic, reclaiming copper
CN108164030A (en) * 2017-12-27 2018-06-15 中国科学院过程工程研究所 The process for fixation of arsenic in a kind of arsenic containing solution

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101830583A (en) * 2010-03-25 2010-09-15 云南铜业股份有限公司 Method for treating waste acid by gypsum sedimentation, arsenic oxidizing sedimentation and iron salt neutralization and co-precipitation
US20120164041A1 (en) * 2010-12-27 2012-06-28 Altynalmas Gold Ltd., a Canada Corporation Stabilization of Arsenic-Containing Wastes Generated During Treatment of Sulfide Ores
CN105753218A (en) * 2016-04-13 2016-07-13 中国科学院过程工程研究所 Method for removing trivalent arsenic
CN107739841A (en) * 2017-10-25 2018-02-27 湖南水口山有色金属集团有限公司 A kind of method for separating arsenic from containing the high copper dross slag of arsenic, reclaiming copper
CN108164030A (en) * 2017-12-27 2018-06-15 中国科学院过程工程研究所 The process for fixation of arsenic in a kind of arsenic containing solution

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
赵凯等: "天然菱铁矿改性及强化除砷研究", 《环境科学》 *

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114314927A (en) * 2022-01-05 2022-04-12 大连理工大学 Co-treatment method for arsenic-containing waste acid and iron and arsenic waste residues
CN114573149A (en) * 2022-04-02 2022-06-03 中国科学院沈阳应用生态研究所 Co-treatment method for arsenic-containing waste acid and arsenic-calcium-containing waste residue
CN114573149B (en) * 2022-04-02 2023-06-30 中国科学院沈阳应用生态研究所 Co-treatment method for waste residues containing arsenic and waste acid and arsenic and calcium
CN117797764A (en) * 2024-02-28 2024-04-02 广东顺控自华科技有限公司 Calcium-based siderite and preparation method and application thereof
CN117797764B (en) * 2024-02-28 2024-06-07 广东顺控自华科技有限公司 Calcium-based siderite and preparation method and application thereof

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