阅读说明：本技术 一种利用改性凹土处理无机废硫酸中重金属的方法 (Method for treating heavy metals in inorganic waste sulfuric acid by using modified attapulgite ) 是由 张俊 杜步云 焦少俊 陈思焜 邵翔 刘聪聪 蔡印萤 杜紫嫣 王俊杰 于 2021-01-11 设计创作，主要内容包括：本发明涉及一种利用改性凹土处理无机废硫酸中重金属的方法,它包括以下步骤：取凹土原料,进行研磨；先用双氧水溶液氧化,再采用酸浸润洗脱后煅烧,然后放置于乙二胺四乙酸二钠和木质素磺酸钠的饱和溶液中,固液分离后,再进行干燥,得到改性的凹土颗粒；将改性的凹土颗粒再进行磨碎,制作改性凹土材料；将其与待处理的含重金属的无机废硫酸充分混合,翻转振荡2h以上,固液分离后,分离出固体废物和硫酸。本发明利用改性凹土材料的吸附与分离,可有效去除无机废硫酸中的重金属,通过多次稳定的处理,可达到90%以上的吸附去除效率,减少了无机废硫酸中重金属的残留量,降低了处理成本,处理后的硫酸可以降级使用或作为生产副产品的原料。(The invention relates to a method for treating heavy metal in inorganic waste sulfuric acid by using modified attapulgite, which comprises the following steps: taking a attapulgite raw material, and grinding; oxidizing with hydrogen peroxide solution, soaking and eluting with acid, calcining, placing in saturated solution of disodium ethylenediamine tetraacetic acid and sodium lignosulfonate, performing solid-liquid separation, and drying to obtain modified attapulgite particles; grinding the modified attapulgite particles to prepare a modified attapulgite material; fully mixing the waste sulfuric acid with heavy metal-containing inorganic waste sulfuric acid to be treated, turning and oscillating for more than 2 hours, and separating solid waste and sulfuric acid after solid-liquid separation. The invention can effectively remove heavy metals in inorganic waste sulfuric acid by utilizing the adsorption and separation of the modified attapulgite material, can achieve more than 90 percent of adsorption removal efficiency through multiple stable treatments, reduces the residual quantity of the heavy metals in the inorganic waste sulfuric acid, reduces the treatment cost, and the treated sulfuric acid can be degraded for use or can be used as a raw material of a production byproduct.)

1. A method for treating heavy metals in inorganic waste sulfuric acid by using modified attapulgite is characterized by comprising the following steps:

(1) grinding attapulgite raw material into particles of not less than 300 meshes;

(2) oxidizing the ground attapulgite particles with a hydrogen peroxide solution, soaking and eluting with acid, and calcining; placing the calcined attapulgite particles into a saturated solution of disodium ethylene diamine tetraacetate and sodium lignosulfonate for infiltration, and drying after solid-liquid separation to obtain modified attapulgite particles;

(3) grinding the modified attapulgite particles again to prepare a modified attapulgite material with the particle size of 90-110 mu m;

(4) fully mixing the modified attapulgite material prepared in the step (3) with inorganic waste sulfuric acid containing heavy metals to be treated according to a solid-liquid ratio of 1: 40-60, performing turnover oscillation for more than 2 hours, and performing solid-liquid separation to obtain solid waste and sulfuric acid;

(5) and (4) repeating the operation of the step (4) for more than 2 times.

2. The method for treating heavy metals in inorganic waste sulfuric acid by using modified attapulgite according to claim 1, wherein in the step (1), the grinding is performed by using an automatic grinder.

3. The method for treating heavy metals in inorganic waste sulfuric acid by using the modified attapulgite clay according to claim 1, wherein in the step (2), the mass concentration of hydrogen peroxide in the hydrogen peroxide solution is 25-35%, preferably 28-32%.

4. The method for treating heavy metals in inorganic waste sulfuric acid by using modified attapulgite according to claim 1, wherein in the step (2), the water-soil ratio of the hydrogen peroxide solution to the ground attapulgite particles is not less than 1:2, preferably 1: 2; the oxidation treatment time is 2-4 h.

5. The method for treating heavy metals in inorganic waste sulfuric acid by using modified attapulgite according to claim 1, wherein in the step (2), a strong acid with a pH of less than 2 is adopted for soaking and elution, and the soaking time is 4-6 h.

6. The method for treating heavy metals in inorganic waste sulfuric acid by using modified attapulgite according to claim 1, wherein in the step (2), the temperature during calcination treatment is 280-320 ℃; the calcining time is 2-4 h, preferably 3 h.

7. The method for treating heavy metals in inorganic waste sulfuric acid by using modified attapulgite according to claim 1, wherein in the step (2), the calcined attapulgite particles are soaked in a saturated solution of disodium ethylenediamine tetraacetic acid and sodium lignosulfonate for 12-24 hours; the temperature during drying is 40-60 ℃; the drying time is 8-12 h.

8. The method for treating heavy metals in inorganic waste sulfuric acid by using modified attapulgite according to claim 1, wherein in the step (3), the modified attapulgite particles are ground again to prepare a modified attapulgite material having a particle size of 100 μm, and an automatic grinding apparatus is used for grinding.

9. The method for treating heavy metals in inorganic waste sulfuric acid by using modified attapulgite according to claim 1, wherein in the step (4), the solid-to-liquid ratio is 1: 50; the overturning speed is 20 r/min-30 r/min; the heavy metal contained in the inorganic waste sulfuric acid is one or more of copper, zinc, nickel or chromium.

10. The method for treating heavy metals in inorganic waste sulfuric acid by using modified attapulgite according to claim 1, wherein in the step (4), the separated solid waste is disposed according to hazardous waste; in step (5), the separated sulfuric acid is used degraded or as a raw material of a production by-product.

Technical Field

The invention belongs to the field of hazardous waste treatment and recycling, and particularly relates to a method for treating heavy metals in inorganic waste sulfuric acid by using modified attapulgite.

Background

According to statistics, the total yield of the waste sulfuric acid in China in 2017 is 9613 ten thousand tons, wherein the inorganic waste sulfuric acid accounts for 35%, and the important production source of the inorganic waste sulfuric acid is metal surface treatment. According to investigation, 15-30 kg of waste acid liquid containing zinc ions and manganese ions is generated per 1 ton of steel products on average; the amount of waste acid solution containing nickel ions and chromium ions is 100-150 kg per 1 ton of stainless steel products.

The harm of inorganic waste sulfuric acid to the environment is far greater than that of common chemical wastewater, and the waste sulfuric acid also reacts with carbonate, sulfite, sulfide and the like in rocks and soil while permeating underground to generate harmful gases such as sulfur dioxide, hydrogen sulfide and the like and is emitted into the air to pollute the atmosphere. Meanwhile, once a large amount of heavy metals contained in the inorganic waste sulfuric acid are dissolved into a river or an underground water system, the river or the underground water system is polluted, and further, the soil is seriously polluted.

The common methods for treating the waste sulfuric acid comprise a neutralization method, a chemical oxidation method, a polymerization method, a high-temperature cracking method, an extraction method, an immersion combustion high-temperature crystallization method, a vacuum concentration freezing crystallization method, a method for producing ferrous sulfate by adding iron scraps, a natural crystallization-diffusion dialysis method, an acid adding freezing crystallization method and the like. At present, domestic hazardous waste operating units generally adopt a neutralization method and a ferrous sulfate production method by adding iron scraps to treat inorganic waste sulfuric acid.

The neutralization method and the method for producing ferrous sulfate by adding iron scraps have the advantages of low investment, simple operation and the like, but are difficult to remove heavy metals in inorganic waste sulfuric acid, and impurities such as heavy metal ions and the like can remain in byproducts. At present, the state lacks corresponding by-product pollutant control standards, and secondary pollution to the environment is easily caused by utilizing and disposing the by-products. Although some related methods have been developed in China for removing heavy metals in inorganic waste sulfuric acid, the problems of immature technology, complex operation, high investment cost and the like are often faced, the applicability and the generalization of the technology are poor, and the disposal cost is additionally increased.

The existing technology for removing heavy metals in inorganic waste sulfuric acid has the problems of few treatment means, high cost, poor popularization and application performance and the like, so that the treatment method which is low in cost, high in removal rate and easy to operate is provided, and the application prospect is good.

Compared with the published 'regeneration treatment method of dangerous solid wastes containing organophosphorus pesticides' (CN 104826854A), the method has the advantages that: firstly, the operation is more convenient, the material is formed in one step, the sodium lignosulfonate solution is not added outside the forehead in the oscillation procedure, and the treatment cost is effectively saved; the calcination process is advanced, so that impurities in the attapulgite are removed, the specific surface area of the attapulgite is effectively increased, the disodium ethylene diamine tetraacetate and the sodium lignosulfonate saturated solution can be adsorbed to a greater extent, and the adsorption performance on heavy metals is enhanced; and thirdly, the oscillation mode of sampling, overturning and oscillating ensures that the modified attapulgite is fully contacted with the inorganic waste sulfuric acid, and the heavy metal ions in the sulfuric acid are efficiently adsorbed.

Disclosure of Invention

The invention aims to provide a method for treating heavy metals in inorganic waste sulfuric acid, which has low cost, high removal rate and easy operation based on the prior art.

The technical scheme of the invention is as follows:

a method for treating heavy metals in inorganic waste sulfuric acid by using modified attapulgite is characterized by comprising the following steps:

(1) grinding the attapulgite raw material into particles of not less than 300 meshes;

(2) oxidizing the ground attapulgite particles with a hydrogen peroxide solution, soaking and eluting with acid, and calcining; placing the calcined attapulgite particles into a saturated solution of disodium ethylene diamine tetraacetate and sodium lignosulfonate for infiltration, and drying after solid-liquid separation to obtain modified attapulgite particles;

(3) grinding the modified attapulgite particles again to prepare a modified attapulgite material with the particle size of 90-110 mu m;

(4) fully mixing the modified attapulgite material prepared in the step (3) with inorganic waste sulfuric acid containing heavy metals to be treated according to a solid-liquid ratio of 1: 40-60, performing turnover oscillation for more than 2 hours, and performing solid-liquid separation to obtain solid waste and sulfuric acid;

(5) and (4) repeating the operation of the step (4) for more than 2 times.

For the present invention, the attapulgite clay raw material is subjected to grinding and modification treatment before the heavy metals in the inorganic waste sulfuric acid are treated. In the step (1), the attapulgite raw material is pretreated and ground using an automatic grinder to make particles of not less than 300 mesh, for example, 300 mesh, to disperse other components inside and to increase the specific surface area and adsorption sites of the attapulgite.

When the ground attapulgite particles are modified, the ground attapulgite particles are firstly oxidized by hydrogen peroxide solution to remove oxidizable substances in the attapulgite particles. In the step (2), during the oxidation treatment, the mass concentration of the hydrogen peroxide in the hydrogen peroxide solution can be adjusted according to the actual situation, and the mass concentration of the hydrogen peroxide in the hydrogen peroxide solution can be, but is not limited to, 25% -35%, for example, the mass concentration of the hydrogen peroxide in the hydrogen peroxide solution is controlled to be 28% -32%, so that a better effect can be achieved.

In step (2), in order to achieve better treatment effect and cost saving, the ratio of the hydrogen peroxide solution to the ground attapulgite particles can be controlled, and in the oxidation treatment of the invention, the water-soil ratio of the hydrogen peroxide solution to the ground attapulgite particles is generally controlled to be not less than 1:2 (the water-soil ratio is ≧ 1: 2), for example, the water-soil ratio is 1: 2. The oxidation treatment time is generally controlled to be 2-4 h, and a better treatment effect can be obtained.

In the step (2), after the crushed attapulgite particles are oxidized, acid is adopted for soaking and elution to remove substances dissolved in acids in the attapulgite particles. In a preferable scheme, strong acid with the pH value of less than 2 is adopted during soaking and elution, and the soaking time is 4-6 h.

In the step (2), the attapulgite particles after acid infiltration and elution are calcined again, and in order to obtain better attapulgite particles, the temperature during calcination treatment is generally controlled to be 280-320 ℃. The calcination time is controlled to be 2 h-4 h, for example, 3 h.

In the step (2), after calcination treatment, the calcined attapulgite particles are placed in a saturated solution of disodium ethylenediamine tetraacetic acid and sodium lignosulfonate for infiltration. The soaking time is 12-24 h. And after solid-liquid separation, drying, wherein the temperature during drying is generally controlled to be 40-60 ℃, and the drying time is generally 8-12 hours.

In the step (3), the modified attapulgite particles are ground again to prepare the modified attapulgite material with the particle size of 90-110 μm. In a preferred scheme, the modified attapulgite particles are ground again to prepare the modified attapulgite material with the particle size of 100 mu m.

For the purposes of the present invention, the inorganic waste acids mentioned are inorganic waste sulfuric acids which contain heavy metals and are relatively stable. Wherein, the heavy metal contained in the inorganic waste acid is one or more of copper, zinc, nickel or chromium.

In a preferable scheme, in the step (4), the modified attapulgite material prepared in the step (3) and inorganic waste sulfuric acid to be treated are fully mixed according to a solid-liquid ratio of 1:50, overturning and oscillating are carried out for more than 2 hours, the overturning speed is 20 r/min-30 r/min, and solid-liquid separation is carried out to obtain solid waste and sulfuric acid.

Chinese patent CN104826854A discloses a regeneration treatment method of dangerous solid waste containing organophosphorus pesticides, which comprises the following steps: taking a attapulgite raw material, and grinding; oxidizing with hydrogen peroxide solution, soaking and eluting with acid to weak acidity, placing in saturated solution of sodium dodecyl benzene sulfonate and sodium lignosulfonate, performing solid-liquid separation, and calcining at high temperature to obtain modified attapulgite; grinding the calcined attapulgite particles to prepare a modified attapulgite material; fully mixing the solid waste with dangerous solid waste containing organophosphorus pesticide to be treated, adding sodium lignosulfonate solution, fully oscillating for more than 1h, and separating solid precipitate after solid-liquid separation. Compared with the patent, the method for treating the heavy metal in the inorganic waste sulfuric acid provided by the invention has the following advantages: (1) after acid infiltration and elution are carried out on the attapulgite particles after oxidation treatment, calcination treatment is firstly carried out to remove impurities in the attapulgite particles and increase the specific surface area of the attapulgite particles, and then the attapulgite particles are placed in a saturated solution of disodium ethylenediamine tetraacetic acid and sodium lignosulfonate for infiltration, so that the adsorption of the attapulgite particles after calcination treatment on the disodium ethylenediamine tetraacetic acid and the saturated solution of sodium lignosulfonate can be promoted, the adsorption performance on heavy metals in inorganic waste sulfuric acid is improved, and the removal efficiency of the heavy metals in the inorganic sulfuric acid reaches over 90 percent. (2) The modified attapulgite material is adopted to treat the inorganic waste sulfuric acid containing heavy metals, sodium lignosulphonate does not need to be added again in the treatment process, the treatment method is more convenient, and the cost is effectively saved. (3) According to the invention, the modified attapulgite material and the inorganic waste sulfuric acid containing heavy metals are mixed in an oscillation mode of turnover oscillation, so that the modified attapulgite material can be fully contacted with the inorganic waste sulfuric acid, and the modified attapulgite material can more easily adsorb heavy metal ions in the inorganic sulfuric acid.

Meanwhile, the inventor of the invention fully mixes the modified attapulgite material prepared by the method disclosed in the Chinese patent CN104826854A with inorganic waste sulfuric acid containing heavy metals to be treated according to the solid-to-liquid ratio of 1:50, turns over and oscillates for more than 2 hours at the turning speed of 20 r/min-30 r/min, and finds that the removal efficiency of the heavy metals in the inorganic waste sulfuric acid is about 65%, and the removal efficiency of the heavy metals in the inorganic waste sulfuric acid is about 67% even after sodium lignosulfonate is added, so that the removal efficiency is not obviously increased. That is, because the objects to be treated are different, a specific modification method needs to be explored to modify the attapulgite raw material, and the obtained modified attapulgite material can obtain better effect.

The inventor of the invention finds that in the step (2), after calcination treatment, the calcined attapulgite particles are soaked in a saturated solution of disodium ethylenediamine tetraacetic acid and sodium lignosulfonate, and the disodium ethylenediamine tetraacetic acid is important when the attapulgite particles are modified, so that the adsorption performance of the modified attapulgite particles on heavy metals in inorganic waste sulfuric acid can be obviously improved. However, other similar compounds in the prior art cannot effectively improve the adsorption performance of heavy metals in inorganic waste sulfuric acid, such as sodium dodecyl benzene sulfonate. In this regard, the present inventors made the following experiments: placing the calcined attapulgite particles into a saturated solution of sodium dodecyl benzene sulfonate and sodium lignin sulfonate for infiltration, separating the attapulgite particles, drying, grinding again to prepare a modified attapulgite material with the particle size of 100 mu m, fully mixing the modified attapulgite material with inorganic waste sulfuric acid containing heavy metals to be treated according to a solid-to-liquid ratio of 1:50, turning over and oscillating for more than 2 hours at a turning over speed of 20 r/min-30 r/min, and finding that the removal efficiency of the heavy metals in the inorganic waste sulfuric acid is low and is only about 30%, and the separated sulfuric acid cannot meet the requirements of degraded use or raw materials as production byproducts.

The inorganic waste sulfuric acid treated by the modified attapulgite material belongs to hazardous waste with higher environmental risk, and the treatment method of the invention is adopted, in the step (4), the separated solid waste is treated according to the hazardous waste, and the wastewater generated in the treatment process enters a sewage treatment system. In step (5), the separated sulfuric acid may be degraded for use or as a raw material for production by-products. The whole treatment process adopts a whole-process risk control method, so that the environmental risk is low.

The attapulgite clay raw material adopted by the invention is a relatively abundant mineral product in China, the reserve of the attapulgite clay is abundant in the downstream coastal mountain areas of Huaihe river in China, the reserve accounts for about more than 30% of the total reserve in the world, the quality of the finished attapulgite clay is relatively good, and compared with activated carbon and the like, the utilization cost is low, the large-scale production and processing are easy, and the popularization is easy. The method utilizes the adsorption and separation of the modified attapulgite material to treat the heavy metals in the inorganic waste sulfuric acid, has the characteristics of low requirement on equipment conditions, high heavy metal removal efficiency of over 90 percent, less pollutant generation, low treatment cost, wide applicable conditions and the like, is suitable for treating and regenerating hazardous wastes such as the inorganic waste sulfuric acid, and is an efficient and energy-saving hazardous waste treatment and regeneration technology.

In a preferred embodiment, the method for treating heavy metals in inorganic waste sulfuric acid by using the modified attapulgite comprises the following detailed steps:

(1) grinding the attapulgite raw material into particles of not less than 300 meshes, and grinding by using an automatic grinding instrument, wherein the particle size of the particles is controlled to reach 300 meshes so as to disperse other internal components and increase the specific surface area and adsorption sites of the attapulgite.

(2) And (3) carrying out oxidation treatment on the ground attapulgite particles by using a hydrogen peroxide solution with the mass concentration of 28-32%, wherein in the oxidation treatment, the water-soil ratio of the hydrogen peroxide solution to the ground attapulgite particles is controlled to be not less than 1:2 (for example, the water-soil ratio is 1: 2), and the treatment time is controlled to be 2-4 h. And after the oxidation treatment is finished, acid infiltration elution is adopted to remove substances dissolved in acids in the attapulgite particles, strong acid with the pH value less than 2 is adopted during infiltration elution, and the infiltration time is 4-6 h. After soaking and elution, calcining at 280-320 ℃ for 2-4 h, for example, 3 h. And (3) placing the calcined attapulgite particles into a saturated solution of disodium ethylenediamine tetraacetic acid and sodium lignosulfonate for soaking for 12-24 h, and after solid-liquid separation, drying the separated attapulgite particles at 40-60 ℃, wherein the drying time is generally 8-12 h, so as to obtain the modified attapulgite particles.

(3) And grinding the modified attapulgite particles again to prepare the modified attapulgite material with the particle size of 90-110 microns (for example, 100 microns).

(4) And (3) fully mixing the modified attapulgite material prepared in the step (3) with inorganic waste sulfuric acid containing heavy metals to be treated according to a solid-to-liquid ratio of 1: 40-60 (for example, 1: 50), overturning and oscillating for more than 2 hours at an overturning speed of 20-30 r/min, and performing solid-liquid separation to obtain solid waste and sulfuric acid. The separated solid waste is disposed according to the hazardous waste, and the wastewater generated in the treatment process enters a sewage treatment system.

(5) And (4) repeating the operation of the step (4) for more than 2 times. The separated sulfuric acid can be degraded for use or used as a raw material for production by-products.

By adopting the technical scheme of the invention, the advantages are as follows:

aiming at the problem of treatment and regeneration of hazardous waste such as inorganic waste sulfuric acid, the invention utilizes the adsorption and separation of the modified attapulgite material to effectively remove heavy metals in the inorganic waste sulfuric acid, and can achieve more than 90 percent of adsorption removal efficiency through multiple stable treatments, reduce the residual quantity of the heavy metals in the inorganic waste sulfuric acid, reduce the treatment cost, and the treated sulfuric acid can be degraded for use or can be used as a raw material of a production byproduct. And the attapulgite clay raw material is a relatively abundant mineral product in China, has high yield, relatively convenient material acquisition and relatively low cost, and is easy to produce and popularize.

The treatment method is simple and easy to implement, has low requirements on equipment conditions, has the characteristics of less pollutant generation, small harmfulness, low treatment cost, wider application conditions and the like, can be applied under extreme conditions such as strong acid and the like, and is an efficient and energy-saving inorganic waste sulfuric acid treatment and regeneration technology.

Detailed Description

The method for treating heavy metals in inorganic waste sulfuric acid by using modified attapulgite according to the present invention is further illustrated by the following examples, which are not intended to limit the present invention in any way.

Example 1:

(1) and (3) grinding the attapulgite raw material by using an automatic grinding instrument, and controlling the particle size of attapulgite particles to be 300 meshes.

(2) After grinding is finished, oxidizing the ground attapulgite particles by using a hydrogen peroxide solution to remove oxidizable substances in the attapulgite particles, and during the oxidizing treatment, controlling the mass concentration of the hydrogen peroxide in the hydrogen peroxide solution to be 30%, keeping the water-soil ratio of the hydrogen peroxide solution to the ground attapulgite particles at 1:2, and treating for 3 hours. And after the oxidation treatment is finished, eluting by using acid, and soaking and eluting by using strong acid with the pH value of less than 2 for 5 h. After soaking and elution, calcining at 300 deg.c for 3 hr. After calcination, adding attapulgite into a saturated solution of disodium ethylene diamine tetraacetate and sodium lignosulfonate, fully soaking for 18h, and then carrying out solid-liquid separation. And then heating and drying the separated attapulgite clay particles at 50 ℃ for 10h to obtain the modified attapulgite clay particles.

(3) And grinding the modified attapulgite particles again to prepare the modified attapulgite material with the particle size of 100 mu m.

(4) And (3) fully mixing the modified attapulgite material prepared in the step (3) with the inorganic waste sulfuric acid containing copper ions to be treated according to a solid-liquid ratio of 1:50, overturning and oscillating for 3 hours at an overturning speed of 25r/min, carrying out solid-liquid separation to obtain solid waste and sulfuric acid, treating the separated solid waste according to dangerous waste, and feeding the wastewater generated in the treatment process into a sewage treatment system.

(5) The separated sulfuric acid is repeated the above step (4). The separated sulfuric acid can be degraded for use or used as a raw material for production by-products.

After the inorganic waste sulfuric acid containing copper ions is fully overturned and oscillated for one time and is subjected to solid-liquid separation, the removal effect of the copper ions in the inorganic waste sulfuric acid containing the copper ions reaches 82 percent. After the inorganic waste sulfuric acid containing copper ions is fully overturned and oscillated for three times and is subjected to solid-liquid separation, the removal effect of the copper ions in the inorganic waste sulfuric acid containing the copper ions reaches 95 percent. This shows that after one-time full-turning oscillation and separation, the copper ion removal effect is obvious, and the content of the copper ions can be reduced to a trace level by multiple treatments.

Example 2:

(1) and (3) grinding the attapulgite raw material by using an automatic grinding instrument, and controlling the particle size of attapulgite particles to be 300 meshes.

(2) After the grinding in the step (1) is finished, oxidizing the ground attapulgite particles by using a hydrogen peroxide solution to remove oxidizable substances in the attapulgite particles, wherein during the oxidizing treatment, the mass concentration of the hydrogen peroxide in the hydrogen peroxide solution is controlled to be 32%, the water-soil ratio of the hydrogen peroxide solution to the ground attapulgite particles is kept at 1:2, and the treatment time is 4 hours. And after the oxidation treatment is finished, eluting by using acid, and soaking and eluting by using strong acid with the pH value of less than 2 for 6 hours. After soaking and elution, calcining at 300 deg.c for 3 hr. After calcination, adding attapulgite into a saturated solution of disodium ethylene diamine tetraacetate and sodium lignosulfonate, fully soaking for 24 hours, and then carrying out solid-liquid separation. And then heating and drying the separated attapulgite clay particles at 50 ℃ for 10h to obtain the modified attapulgite clay particles. And grinding the modified attapulgite particles again to prepare the modified attapulgite material with the particle size of 100 mu m.

(3) After the grinding in the step (1) is finished, oxidizing the ground attapulgite particles by using a hydrogen peroxide solution to remove oxidizable substances in the attapulgite particles, wherein during the oxidizing treatment, the mass concentration of the hydrogen peroxide in the hydrogen peroxide solution is controlled to be 32%, the water-soil ratio of the hydrogen peroxide solution to the ground attapulgite particles is kept at 1:2, and the treatment time is 4 hours. And after the oxidation treatment is finished, eluting by using acid, and soaking and eluting by using strong acid with the pH value of less than 2 for 6 hours. After soaking and elution, calcining at 300 deg.c for 3 hr. After calcination, the attapulgite is added into a saturated solution of sodium dodecyl benzene sulfonate and sodium lignin sulfonate, and after full infiltration for 24 hours, solid-liquid separation is carried out. And then heating and drying the separated attapulgite clay particles at 50 ℃ for 10h to obtain the modified attapulgite clay particles. And grinding the modified attapulgite particles again to prepare the modified attapulgite material with the particle size of 100 mu m.

(4) And (2) grinding the grinded attapulgite particles obtained in the step (1) again to prepare the attapulgite material with the particle size of 100 microns.

(5) And (3) fully mixing the attapulgite material prepared in the step (2), the step (3) and the step (4) and modified attapulgite particles with the particle size of 100 microns prepared in the example 1 of Chinese patent CN104826854A with inorganic waste sulfuric acid containing zinc ions to be treated according to the solid-to-liquid ratio of 1:50, overturning and oscillating for 3 hours at the overturning speed of 30r/min, carrying out solid-liquid separation to obtain solid waste and sulfuric acid, treating the separated solid waste according to hazardous waste, and feeding the wastewater generated in the treatment process into a sewage treatment system.

(6) The separated sulfuric acid is repeated the above step (5). The separated sulfuric acid can be degraded for use or used as a raw material for production by-products.

After the mixture is fully turned and oscillated for three times and subjected to solid-liquid separation, the removal effect of zinc ions in the inorganic waste sulfuric acid treated by the modified attapulgite material in the step (2) is 98%, the removal effect of zinc ions in the inorganic waste sulfuric acid treated by the modified attapulgite material in the step (3) is 60%, and the removal effect of zinc ions in the inorganic waste sulfuric acid treated by the unmodified attapulgite material in the step (4) is 53%. The removal effect of zinc ions in the inorganic waste sulfuric acid treated by the modified attapulgite particles prepared in example 1 in the Chinese patent CN104826854A is 65%, which shows that the removal effect of the attapulgite material modified in the step (2) on the zinc ions is more obvious.

Example 3:

(1) and (3) grinding the attapulgite raw material by using an automatic grinding instrument, and controlling the particle size of attapulgite particles to be 300 meshes.

(2) After the grinding in the step (1) is finished, oxidizing the ground attapulgite particles by using a hydrogen peroxide solution to remove oxidizable substances in the attapulgite particles, wherein during the oxidizing treatment, the mass concentration of the hydrogen peroxide in the hydrogen peroxide solution is controlled to be 30%, the water-soil ratio of the hydrogen peroxide solution to the ground attapulgite particles is kept at 1:2, and the treatment time is 3 hours. And after the oxidation treatment is finished, eluting by using acid, and soaking and eluting by using strong acid with the pH value of less than 2 for 5 h. After soaking and elution, calcining at 300 deg.c for 3 hr. After calcination, adding attapulgite into a saturated solution of disodium ethylene diamine tetraacetate and sodium lignosulfonate, fully soaking for 18h, and then carrying out solid-liquid separation. And then heating and drying the separated attapulgite clay particles at 50 ℃ for 10h to obtain the modified attapulgite clay particles. And grinding the modified attapulgite particles again to prepare the modified attapulgite material with the particle size of 100 mu m.

(3) After the grinding in the step (1) is finished, oxidizing the ground attapulgite particles by using a hydrogen peroxide solution, wherein during the oxidizing treatment, the mass concentration of the hydrogen peroxide in the hydrogen peroxide solution is controlled to be 35%, the water-soil ratio of the hydrogen peroxide solution to the ground attapulgite particles is kept at 1:3, and the treatment time is 3 hours. And after the oxidation treatment is finished, eluting by using acid, and soaking and eluting by using strong acid with the pH value of less than 2 for 5 h. After soaking and elution, calcining at 300 deg.c for 2 hr. After calcination, adding attapulgite into a saturated solution of disodium ethylene diamine tetraacetate and sodium lignosulfonate, fully soaking for 18h, and then carrying out solid-liquid separation. And then heating and drying the separated attapulgite clay particles at 50 ℃ for 10h to obtain the modified attapulgite clay particles. And grinding the modified attapulgite particles again to prepare the modified attapulgite material with the particle size of 100 mu m.

(4) Fully mixing the modified attapulgite material prepared in the step (2) and the modified attapulgite material prepared in the step (3) with the inorganic waste sulfuric acid containing nickel ions to be treated according to the solid-liquid ratio of 1:50, overturning and oscillating for 3h at the overturning speed of 25r/min, performing solid-liquid separation to obtain solid waste and sulfuric acid, treating the separated solid waste according to dangerous waste, and feeding the wastewater generated in the treatment process into a sewage treatment system.

(5) The separated sulfuric acid is repeated the above step (4). The separated sulfuric acid can be degraded for use or used as a raw material for production by-products.

And (3) after the mixture is fully overturned and oscillated for three times and solid-liquid separation, the removal effect of the nickel ions in the inorganic waste sulfuric acid treated by the modified attapulgite material in the step (2) is 96%. The removal effect of nickel ions in the inorganic waste sulfuric acid treated by the modified attapulgite material in the step (3) is 90%. This indicates that the attapulgite material modified under the preferred conditions provides better removal of nickel ions.

Example 4:

(1) and (3) grinding the attapulgite raw material by using an automatic grinding instrument, and controlling the particle size of attapulgite particles to be 300 meshes.

(2) After grinding is finished, oxidizing the ground attapulgite particles by using a hydrogen peroxide solution to remove oxidizable substances in the attapulgite particles, and during the oxidizing treatment, controlling the mass concentration of the hydrogen peroxide in the hydrogen peroxide solution to be 28%, keeping the water-soil ratio of the hydrogen peroxide solution to the ground attapulgite particles at 1:2, and treating for 3 hours. And after the oxidation treatment is finished, eluting by using acid, and soaking and eluting by using strong acid with the pH value of less than 2 for 4 hours. After soaking and elution, calcining at 300 deg.c for 3 hr. After calcination, adding attapulgite into a saturated solution of disodium ethylenediamine tetraacetic acid and sodium lignosulphonate, fully soaking for 20 hours, and then carrying out solid-liquid separation. And then heating and drying the separated attapulgite clay particles at 60 ℃ for 12h to obtain the modified attapulgite clay particles.

(3) And grinding the modified attapulgite particles again to prepare the modified attapulgite material with the particle size of 100 mu m.

(4) Fully mixing the modified attapulgite material prepared in the step (3) with inorganic waste sulfuric acid containing chromium ions to be treated according to a solid-liquid ratio of 1:50, overturning and oscillating for 3 hours at an overturning speed of 25r/min, carrying out solid-liquid separation to obtain solid waste and sulfuric acid, treating the separated solid waste according to dangerous waste, and feeding wastewater generated in the treatment process into a sewage treatment system.

(5) The separated sulfuric acid is repeated the above step (4). The separated sulfuric acid can be degraded for use or used as a raw material for production by-products.

After the inorganic waste sulfuric acid containing chromium ions is fully overturned and oscillated for three times and is subjected to solid-liquid separation, the removal effect of the chromium ions in the inorganic waste sulfuric acid containing chromium ions reaches 96 percent.

Example 5:

(1) and (3) grinding the attapulgite raw material by using an automatic grinding instrument, and controlling the particle size of attapulgite particles to be 300 meshes.

(2) After grinding is finished, oxidizing the ground attapulgite particles by using a hydrogen peroxide solution to remove oxidizable substances in the attapulgite particles, and during the oxidizing treatment, controlling the mass concentration of the hydrogen peroxide in the hydrogen peroxide solution to be 30%, keeping the water-soil ratio of the hydrogen peroxide solution to the ground attapulgite particles at 1:2, and treating for 4 hours. And after the oxidation treatment is finished, eluting by using acid, and soaking and eluting by using strong acid with the pH value of less than 2 for 6 hours. After soaking and elution, calcining at 300 deg.c for 3 hr. After calcination, adding attapulgite into a saturated solution of disodium ethylene diamine tetraacetate and sodium lignosulfonate, fully soaking for 18h, and then carrying out solid-liquid separation. And then heating and drying the separated attapulgite clay particles at 50 ℃ for 12h to obtain the modified attapulgite clay particles.

(3) And grinding the modified attapulgite particles again to prepare the modified attapulgite material with the particle size of 100 mu m.

(4) And (3) fully mixing the modified attapulgite material prepared in the step (3) with inorganic waste sulfuric acid containing copper ions, zinc ions, nickel ions and chromium ions to be treated according to a solid-liquid ratio of 1:50, carrying out turnover oscillation for 3h at a turnover speed of 25r/min, carrying out solid-liquid separation to obtain solid waste and sulfuric acid, treating the separated solid waste according to dangerous waste, and feeding wastewater generated in the treatment process into a sewage treatment system.

(5) The separated sulfuric acid is repeated the above step (4). The separated sulfuric acid can be degraded for use or used as a raw material for production by-products.

After the mixture is fully overturned and oscillated for three times and is subjected to solid-liquid separation, the removal effect of copper ions is 92%, the removal effect of zinc ions is 94%, the removal effect of nickel ions is 91% and the removal effect of chromium ions is 90% in the inorganic waste sulfuric acid containing 4 kinds of heavy metal ions including copper ions, zinc ions, nickel ions and chromium ions.

The above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: modifications of the technical solutions described in the foregoing embodiments are still possible, or some technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.