Preparation method of chitosan resin and heavy metal ion adsorption device

Abstract

The invention discloses a chitosan resin preparation method, which comprises: dissolving chitosan in acetic acid, adding epoxy chloropropane, and stirring to carry out cross-linking; filling the cross-linked chitosan into a trace solution sample injector, and dropwise adding the cross-linked chitosan into an NAOH solution to prepare chitosan microspheres; thoroughly cleaning the obtained chitosan microspheres with deionized water, and adding the cleaned chitosan microspheres into a solution containing template ions for imprinting; performing template ion elution on the microspheres subjected to imprinting treatment, and performing freeze drying on the eluted resin to obtain imprinted cross-linked chitosan resin; chitosan is subjected to chemical crosslinking modification, so that the strength, acid-base stability and reusability of chitosan molecules can be improved, meanwhile, imprinting treatment is performed, the chitosan adsorption selectivity is improved, and a self-adjusting unit can adaptively press chitosan resin when the water pressure becomes high, so that the chitosan resin always keeps an optimal adsorption gap, and the adsorption efficiency of the chitosan resin is improved. Therefore, the adsorption rate of heavy metal ions is improved.

Description

Technical Field

[0001] The invention relates to the technical field of forest stand growth models, and in particular to a heavy metal ion adsorption device. Background Art

[0002] In the adsorption method, various pollutants in sewage are effectively absorbed by porous adsorbents, thereby effectively purifying sewage. It mainly absorbs various heavy metal ions in sewage and eliminates them. In wastewater treatment, there are many ions that combine well with adsorbents, which affects the removal of heavy metals. Chitosan has primary hydroxyl, secondary hydroxyl and amino / acetylamino reaction functional groups in its structure. These active functional groups give chitosan excellent adsorption capacity and have a good removal effect on heavy metal ions in water.

[0003] However, the existing chitosan has poor stability and reusability, and the chitosan selectivity is low;

[0004] Moreover, when chitosan in the exchange column adsorbs heavy metal ions in sewage, the water pressure is not constant during injection. When the water pressure is high, the distance between the chitosans will increase when the water pressure touches the chitosan, making it impossible to maintain the most suitable gap between the chitosans, resulting in a poor adsorption rate for heavy metal ions. Summary of the invention

[0005] The purpose of this section is to summarize some aspects of embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the specification abstract and the invention title of this application to avoid blurring the purpose of this section, the specification abstract and the invention title, and such simplifications or omissions cannot be used to limit the scope of the present invention.

[0006] The present invention is proposed in view of the problem that the gaps in chitosan in the above-mentioned existing heavy metal ion adsorption device increase due to the increase of water pressure.

[0007] Therefore, the object of the present invention is to provide a method for preparing chitosan resin and a heavy metal ion adsorption device.

[0008] In order to solve the above technical problems, the present invention provides the following technical solution: a method for preparing chitosan resin, comprising the following steps:

[0009] Chitosan was dissolved in acetic acid, and then epichlorohydrin was added and stirred for cross-linking;

[0010] The cross-linked chitosan was loaded into a micro-solution injector and dripped into the NAOH solution drop by drop to prepare chitosan microspheres;

[0011] The obtained chitosan microspheres were thoroughly washed with deionized water, and the washed chitosan microspheres were added into a solution containing template ions for imprinting;

[0012] The imprinted microspheres are subjected to template ion elution, and the eluted resin is freeze-dried to obtain imprinted cross-linked chitosan resin.

[0013] As a preferred solution of the preparation method of the chitosan resin of the present invention, the chitosan accounts for 2% of the total mass of acetic acid and chitosan, and epichlorohydrin is added and stirred for 24 hours for cross-linking.

[0014] As a preferred embodiment of the method for preparing the chitosan resin of the present invention, the cross-linked chitosan is loaded into a micro-solution injector and dripped into the NAOH solution drop by drop, specifically, the dripping speed is controlled to be 1 to 5 drops per minute to ensure uniform formation of chitosan microspheres.

[0015] As a preferred solution of the method for preparing chitosan resin of the present invention, the imprinted microspheres are subjected to template ion elution, specifically, the pH value is controlled between 3 and 5 during the elution process to improve the elution efficiency and reduce the loss of resin.

[0016] As a preferred embodiment of the method for preparing chitosan resin of the present invention, the eluted resin is freeze-dried, specifically at -40°C to -80°C for 24 to 48 hours to ensure the stability and drying effect of the resin.

[0017] A heavy metal ion adsorption device, comprising:

[0018] The exchange unit comprises an outer cylinder, an inner cylinder arranged on the outer cylinder, a receiving groove arranged on the inner cylinder, a flow hole arranged on the inner cylinder, an outflow pipe arranged on the outer cylinder, a closing cover arranged on the top side of the outer cylinder, a pressing ring arranged on the closing cover, an inflow pipe arranged on the closing cover, and a chitosan resin arranged in the receiving groove;

[0019] The self-adjusting unit comprises a partition plate arranged on the pressing ring, an adaptive component arranged on the partition plate, a rotating component arranged in the partition plate, a bending component arranged in the partition plate, and a pressing component arranged on the pressing ring.

[0020] As a preferred solution of the heavy metal ion adsorption device of the present invention, the adaptive component includes a fixed spring arranged on the partition, a piston block arranged on the fixed spring, and a feeler rod arranged on the piston block.

[0021] As a preferred solution of the heavy metal ion adsorption device described in the present invention, the rotating component includes a rotating ring arranged inside the partition, an arc groove arranged on the rotating ring, a through hole arranged on the partition, and a bearing arranged on the rotating ring.

[0022] As a preferred solution of the heavy metal ion adsorption device described in the present invention, the bending component includes a rectangular groove arranged in the partition, a fixed axis arranged on the rectangular groove, a bending rod arranged on the fixed axis, and a sphere arranged on the bending rod.

[0023] As a preferred solution of the heavy metal ion adsorption device described in the present invention, the pressing and holding assembly includes an installation cavity arranged on the pressing ring, a moving ring arranged on the installation cavity, a pressing and holding ring arranged on the moving ring, a fixed plate arranged on the moving ring, and a telescopic rod arranged on the moving ring.

[0024] The beneficial effects of the present invention are as follows: by chemically cross-linking and modifying chitosan, the strength, acid-base stability and reusability of chitosan molecules can be improved; at the same time, imprinting treatment is performed to improve the selectivity of chitosan adsorption; and the self-regulating unit can adaptively compress the chitosan resin when the water pressure becomes high, so that the chitosan resin always maintains the optimal adsorption gap, thereby improving the adsorption rate of heavy metal ions. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor. Among them:

[0026] Figure 1 It is a schematic diagram of the overall structure of the heavy metal ion adsorption device of the present invention.

[0027] Figure 2 It is a schematic diagram of the structure of the compression ring of the heavy metal ion adsorption device of the present invention.

[0028] Figure 3 for Figure 2 A schematic diagram of the enlarged structure in the middle.

[0029] Figure 4 This is a schematic diagram of the fixed spring structure of the heavy metal ion adsorption device of the present invention.

[0030] Figure 5 It is a schematic diagram of the cross-sectional structure of the heavy metal ion adsorption device of the present invention.

[0031] Figure 6 This is a schematic diagram of the structure of the closing cover of the heavy metal ion adsorption device of the present invention.

[0032] Figure 7 This is a schematic diagram of the bottom structure of the rotating circle of the heavy metal ion adsorption device of the present invention.

[0033] Figure 8 The schematic diagram is a flow chart of the preparation method of chitosan resin of the present invention. DETAILED DESCRIPTION

[0034] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0035] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0036] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0037] Secondly, the present invention is described in detail with reference to the schematic diagram. When describing the embodiments of the present invention in detail, for the sake of convenience, the cross-sectional diagrams showing the device structure will not be partially enlarged according to the general scale, and the schematic diagrams are only examples, which should not limit the scope of protection of the present invention. In addition, in actual production, the three-dimensional dimensions of length, width and depth should be included.

[0038] Example 1

[0039] Reference Figure 8 , which is the first embodiment of the present invention, provides a method for preparing chitosan resin, comprising the following steps:

[0040] S1, dissolving chitosan in acetic acid, then adding epichlorohydrin and stirring for cross-linking;

[0041] Chitosan accounts for 2% of the total mass of acetic acid and chitosan, and epichlorohydrin is added and stirred for 24 hours for cross-linking;

[0042] S2, loading the cross-linked chitosan into a micro-solution injector, and dripping it dropwise into the NAOH solution to prepare chitosan microspheres;

[0043] The cross-linked chitosan was loaded into a micro-solution injector and dripped into the NAOH solution drop by drop, specifically, the dripping speed was controlled to be 1 to 5 drops per minute to ensure uniform formation of chitosan microspheres;

[0044] S3, washing the obtained chitosan microspheres thoroughly with deionized water, and adding the washed chitosan microspheres into a solution containing template ions for imprinting;

[0045] The imprinted microspheres are subjected to template ion elution, specifically, the pH value is controlled between 3 and 5 during the elution process to improve the elution efficiency and reduce the loss of the resin;

[0046] S4, eluting the template ions from the imprinted microspheres, freeze-drying the eluted resin, and obtaining an imprinted cross-linked chitosan resin;

[0047] The eluted resin is freeze-dried, specifically at -40°C to -80°C for 24 to 48 hours to ensure the stability and drying effect of the resin.

[0048] Example 2

[0049] Reference Figure 1 and Figure 2 , which is the second embodiment of the present invention, provides a heavy metal ion adsorption device, including an exchange unit 100 and a self-regulating unit 200. Sewage is injected into the exchange unit 100, and the heavy metal ions are adsorbed by the internal chitosan resin 109, and then flow out of the exchange unit 100. The obtained imprinted cross-linked chitosan resin 109 is loaded into the exchange column, and a dynamic column passing method is adopted to make the thermal power plant wastewater containing Pb2+, Hg2+ and Cd2+ concentrations of 0.5g / L respectively flow through the resin for adsorption treatment.

[0050] Specifically, the exchange unit 100 includes an outer cylinder 101, an inner cylinder 102 installed inside the outer cylinder 101, the inner cylinder 102 is provided with a receiving groove 103 from top to bottom, and the top opening of the receiving groove 103 is exposed at the top of the outer cylinder 101, the inner wall of the inner cylinder 102 is provided with a flow hole 104, an outflow pipe 105 is installed at the bottom of the outer cylinder 101, a closing cover 106 is installed on the top side of the outer cylinder 101, a tightening ring 107 is installed at the bottom of the closing cover 106, an inflow pipe 108 is installed on the top of the closing cover 106, and the interior of the receiving groove 103 is filled with chitosan resin 109.

[0051] The rest of the structure is the same as that of Example 1.

[0052] Operation process: sewage flows into the inner cylinder 102 from the inlet pipe 108, and the sewage flows through the holding tank 103 through the flow hole 104, so that the chitosan resin 109 in the holding tank 103 adsorbs heavy metal ions, and the adsorbed sewage flows to the outside of the inner cylinder 102, and flows out from the outlet pipe 105 from the inner bottom wall of the outer cylinder 101, thereby completing the adsorption of heavy metal ions, and the resin rich in heavy metal ions can be eluted and regenerated, and the acid solution used for elution can be composed of one or more of hydrochloric acid, sulfuric acid or chloroacetic acid.

[0053] Example 3

[0054] Reference Figure 2-Figure 7 , which is the third embodiment of the present invention, and this embodiment is different from the above embodiments in that: a self-adjusting unit 200 includes a partition 201 arranged on a clamping ring 107, an adaptive component 202 is installed at the bottom of the partition 201, a rotating component 203 is installed on the inner wall of the partition 201, a bending component 204 is installed on the inner wall of the partition 201, and a holding component 205 is installed on the inner wall of the clamping ring 107. The adaptive component 202 adjusts its own position according to the water pressure, and the adaptive component 202 moves through the rotating component 203 and the bending component 204 to drive the holding component 205 to move, so that the downward pressure received by the chitosan resin 109 conflicts with the water pressure, thereby keeping the chitosan gap unchanged.

[0055] Specifically, the adaptive component 202 includes a fixed spring 202a arranged on the partition 201, a piston block 202b arranged on the fixed spring 202a, and a feeler rod 202c arranged on the piston block 202b. The inlet pipe 108 extends to the bottom side of the piston block 202b, and the piston block 202b is connected to the inlet pipe 108 by a sealing gasket, so that the piston block 202b remains airtight when moving on the inlet pipe 108, and when the piston block 202b is installed, the outer wall of the piston block 202b fits with the inner wall of the inner cylinder 102, and when the inlet pipe 108 is injected with sewage, the sewage is blocked by the piston block 202b.

[0056] Furthermore, the rotating assembly 203 includes a rotating circle 203a arranged inside the partition 201, the bottom wall of the rotating circle 203a is provided with an arc groove 203b, the bottom of the partition 201 is provided with a through hole 203c, the through hole 203c is located at the bottom of the arc groove 203b, and a bearing 203d is installed on the top of the rotating circle 203a, and the bearing 203d supports the rotating circle 203a.

[0057] Further, the bending assembly 204 includes a rectangular groove 204a disposed in the partition 201, a fixed shaft 204b is installed on the inner wall of the rectangular groove 204a, a bending rod 204c is installed on the outer wall of the fixed shaft 204b, and a ball 204d is installed on one end of the bending rod 204c;

[0058] The bending assembly 204 also includes a trigger block 204e installed on the outer wall of the rotating circle 203a, and an arc-shaped slide groove 204f arranged on the trigger block 204e, and its ball 204d is in contact with the arc-shaped slide groove 204f accordingly. The rotation of the rotating circle 203a can drive the ball 204d to slide and rise along the sliding groove.

[0059] Furthermore, the holding assembly 205 includes an installation cavity 205a arranged on the clamping ring 107, a moving ring 205b is installed on the inner wall of the installation cavity 205a, a holding ring 205c is installed on the inner wall of the moving ring 205b, a fixed plate 205d is installed on the top of the moving ring 205b, and the bottom of the fixed plate 205d is embedded in the moving ring 205b, so that the fixed plate 205d can be extended and retracted on the moving ring 205b, thereby ensuring that the bending rod 204c can apply downward pressure to the moving ring 205b when it is bent, and a telescopic rod 205e is installed on the top of the moving ring 205b, and the telescopic rod 205e supports the moving ring 205b.

[0060] The rest of the structure is the same as that of Example 2.

[0061] Operation process: When the closing cover 106 is locked on the outer cylinder 101, the pressing ring 107 is embedded in the receiving groove 103 to initially compress the chitosan resin 109 in the receiving groove 103, and the piston block 202b moves to the inside of the inner cylinder 102 in contact with the inner wall of the inner cylinder 102. When the water pressure inside the inner cylinder 102 increases, the water pressure triggers the piston block 202b to move upward, and the movement of the piston block 202b drives the three groups of feelers 202c to move upward synchronously. The feeler rods 202c extend through the through holes 203c to the bottom side of the arc groove 203b of the rotating circle 203a, and the feeler rods 202c move upward to squeeze the arc groove 203b, causing the rotating circle 203a to rotate. The rotating circle 203a rotates with The movable trigger block 204e rotates, and the arc-shaped slide groove 204f of the trigger block 204e can drive one end of the ball 204d of the bending rod 204c to lift upward. At this time, the other end of the bending rod 204c drives the fixed plate 205d to move downward, and the movement of the fixed plate 205d drives the moving circle 205b to move downward, and the moving circle 205b drives the holding circle 205c to move. The holding circle 205c applies downward pressure on the chitosan resin 109, and its downward pressure can be balanced with the pressure of the water pressure on the chitosan resin 109, so that when the water pressure increases, the chitosan resin 109 still maintains the original gap, so that the optimal adsorption gap can be maintained, which effectively improves the adsorption rate of the chitosan resin 109 to heavy metal ions.

[0062] Importantly, it should be noted that the construction and arrangement of the present application shown in a plurality of different exemplary embodiments are only exemplary. Although only a few embodiments are described in detail in this disclosure, it should be readily understood by those who refer to this disclosure that many modifications are possible (e.g., the size, scale, structure, shape and proportion of various elements, and parameter values ​​(e.g., temperature, pressure, etc.), installation arrangement, use of materials, color, directional changes, etc.) without substantially departing from the novel teachings and advantages of the subject matter described in the application. For example, the element shown as integrally formed can be composed of multiple parts or elements, the position of the element can be inverted or otherwise changed, and the nature or number or position of the discrete element can be changed or changed. Therefore, all such modifications are intended to be included in the scope of the present invention. The order or sequence of any process or method steps can be changed or reordered according to alternative embodiments. In the claims, any "device plus function" clause is intended to cover the structure of performing the function described herein, and is not only structurally equivalent but also equivalent structure. Without departing from the scope of the present invention, other replacements, modifications, changes and omissions can be made in the design, operating conditions and arrangement of the exemplary embodiments. Therefore, the invention is not limited to a specific embodiment, but extends to several modifications still falling within the scope of the appended claims.

[0063] Additionally, in order to provide a concise description of exemplary embodiments, all features of an actual embodiment (ie, those features that are not relevant to the best mode presently contemplated for carrying out the invention or those that are not relevant to implementing the invention) may not be described.

[0064] It will be appreciated that in the development of any actual implementation, as in any engineering or design project, numerous implementation-specific decisions may be made. Such a development effort may be complex and time-consuming, but will be a routine task of design, fabrication, and production for those of ordinary skill having the benefit of this disclosure without undue experimentation.

[0065] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A method for preparing chitosan resin, characterized in that: The following steps are involved: Chitosan was dissolved in acetic acid, and then epichlorohydrin was added and stirred for cross-linking; The cross-linked chitosan was loaded into a micro-solution injector and dripped into the NAOH solution drop by drop to prepare chitosan microspheres; The obtained chitosan microspheres were thoroughly washed with deionized water, and the washed chitosan microspheres were added into a solution containing template ions for imprinting; The imprinted microspheres are subjected to template ion elution, and the eluted resin is freeze-dried to obtain imprinted cross-linked chitosan resin.

2. The method for preparing chitosan resin according to claim 1, wherein: The chitosan accounts for 2% of the total mass of acetic acid and chitosan, and epichlorohydrin is added and stirred for 24 hours for cross-linking.

3. The method for preparing chitosan resin according to claim 1, wherein: The cross-linked chitosan is loaded into a micro-solution injector and dripped into the NAOH solution drop by drop. Specifically, the dripping speed is controlled to be 1 to 5 drops per minute to ensure uniform formation of chitosan microspheres.

4. The method for preparing chitosan resin according to claim 1, wherein: The imprinted microspheres are subjected to template ion elution, specifically, the pH value is controlled between 3 and 5 during the elution process to improve the elution efficiency and reduce the loss of the resin.

5. The method for preparing chitosan resin according to claim 1, wherein: The eluted resin is freeze-dried, specifically at -40°C to -80°C for 24 to 48 hours to ensure the stability and drying effect of the resin.

6. A heavy metal ion adsorption device, characterized in that: Applicable to the method for preparing chitosan resin according to any one of claims 1 to 5, the heavy metal ion adsorption device comprises: The exchange unit (100) comprises an outer cylinder (101), an inner cylinder (102) arranged on the outer cylinder (101), a receiving groove (103) arranged on the inner cylinder (102), a flow hole (104) arranged on the inner cylinder (102), an outflow pipe (105) arranged on the outer cylinder (101), a closing cover (106) arranged on the top side of the outer cylinder (101), a pressing ring (107) arranged on the closing cover (106), an inflow pipe (108) arranged on the closing cover (106), and a chitosan resin (109) arranged in the receiving groove (103); The self-adjusting unit (200) comprises a partition (201) arranged on the clamping ring (107), an adaptive component (202) arranged on the partition (201), a rotating component (203) arranged in the partition (201), a bending component (204) arranged in the partition (201), and a holding component (205) arranged on the clamping ring (107).

7. The heavy metal ion adsorption device according to claim 6, characterized in that: The adaptive component (202) comprises a fixed spring (202a) arranged on the partition (201), a piston block (202b) arranged on the fixed spring (202a), and a touch rod (202c) arranged on the piston block (202b).

8. The heavy metal ion adsorption device according to claim 7, characterized in that: The rotating assembly (203) comprises a rotating ring (203a) arranged inside the partition (201), an arcuate groove (203b) arranged on the rotating ring (203a), a through hole (203c) arranged on the partition (201), and a bearing (203d) arranged on the rotating ring (203a).

9. The heavy metal ion adsorption device according to claim 8, characterized in that: The bending assembly (204) comprises a rectangular groove (204a) arranged in the partition (201), a fixed shaft (204b) arranged on the rectangular groove (204a), a bending rod (204c) arranged on the fixed shaft (204b), and a sphere (204d) arranged on the bending rod (204c).

10. The heavy metal ion adsorption device according to claim 9, characterized in that: The holding assembly (205) comprises an installation cavity (205a) arranged on a clamping ring (107), a moving ring (205b) arranged on the installation cavity (205a), a holding ring (205c) arranged on the moving ring (205b), a fixing plate (205d) arranged on the moving ring (205b), and a telescopic rod (205e) arranged on the moving ring (205b).

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