Acid-base buffer filter element and application thereof

Abstract

The application discloses an acid-base buffer filter element and application. The filter element comprises 38%-62% activated carbon, 13%-42% weak acid type sodium type ion exchange resin and 18%-42% weak acid type hydrogen type ion exchange resin, and the above percentages are the mass percentages of the components in the filter element respectively. The filter element adjusts the proportion of the activated carbon, the hydrogen type resin and the sodium type resin to construct a weak acid strong base salt buffer system. The water filtered by the filter element is not affected in other indexes, and more importantly, the water quality pH value is stabilized in the range of weak alkaline water (for example, the pH value can be 7.0-7.5 weak alkaline), so that the over-acid or over-alkaline is avoided, and the drinking experience is further improved. The filter element can be applied after the nanofiltration membrane or the reverse osmosis membrane filter element in the filtration process, the sodium ions in the filter element are not exchanged, the sodium ion content of the produced water is basically unchanged, and the burden of the excessive sodium ions on the human body does not need to be worried.

Description

TECHNICAL FIELD

[0001] The application provides an acid-base buffer filter element and application. BACKGROUND

[0002] At present, most household water purifiers adopt nanofiltration or reverse osmosis technology, which removes impurities in water while removing most of the hardness and alkalinity substances in water, so that the carbonate and bicarbonate which originally make the drinking water present weak alkaline are greatly reduced. While exposed to air, affected by acidic gases such as carbon dioxide, the drinking water presents weak acidity, which may cause adverse effects on taste.

[0003] At present, most acid-base adjusting filter elements are mineralization filter elements, and the mineralization material has problems of turbidity exceeding the standard and some heavy metal ions exceeding the standard in the long-term soaking process, and the range of pH adjustment is difficult to control, and the safety of drinking water is difficult to guarantee. This problem needs to be solved urgently. SUMMARY

[0004] The technical problem to be solved by the application is to overcome the defects in the prior art that most acid-base adjusting filter elements are mineralization filter elements, the mineralization material has problems of turbidity exceeding the standard and some heavy metal ions exceeding the standard in the long-term soaking process, the range of pH adjustment is difficult to control, and the safety of drinking water is difficult to guarantee, and an acid-base buffer filter element and application are provided.

[0005] The application solves the above technical problems through the following technical scheme.

[0006] The application provides an acid-base buffer filter element, which comprises 38%-62% of activated carbon, 13%-42% of weak acid type sodium type ion exchange resin and 18%-42% of weak acid type hydrogen type ion exchange resin, and the above percentages are the mass percentages of each component in the acid-base buffer filter element.

[0007] In the application, the activated carbon can be coal-made carbon or coconut shell activated carbon, and is preferably coconut shell activated carbon.

[0008] In the application, the particle size of the activated carbon is preferably 8-30 mesh.

[0009] In the application, the iodine adsorption value of the activated carbon is preferably 800-1500 mg / g.

[0010] In the application, the methylene blue adsorption value of the activated carbon is preferably greater than or equal to 9 mL / 0.1 g.

[0011] In the application, the content of ash in the activated carbon can be 8-15%.

[0012] In the application, the wear resistance of the activated carbon can be 90-98%.

[0013] In the present application, the moisture content of the activated carbon can be 3-8%.

[0014] In the acid-base buffer filter element of the present application, the three components cooperate with each other, the amount of the activated carbon needs to be controlled in the range of 38-62%, the amount of the weak acid type sodium type ion exchange resin needs to be controlled in the range of 13%-42%, and the amount of the weak acid type hydrogen type ion exchange resin needs to be controlled in the range of 18%-42%. If the amount of the activated carbon is less than 38%, the trace organic matter in the filtered water cannot be removed, and the taste of the filtered water cannot be improved. If the amount of the weak acid type hydrogen type ion exchange resin is too much, the filtered water is acidic, and the pH value can be lower than 6.5. If the amount of the weak acid type hydrogen type ion exchange resin is too little, the filtered water is alkaline, and the pH value can be higher than 8.5.

[0015] In the present application, the amount of the activated carbon is preferably 40%-60%, for example, 45%, 50% or 55%.

[0016] In the present application, the amount of the weak acid type hydrogen type ion exchange resin is preferably 15%-40%, for example, 20%, 25%, 30% or 35%.

[0017] In the present application, the amount of the weak acid type sodium type ion exchange resin is preferably 20%-40%, for example, 25%, 30% or 35%.

[0018] In the present application, the mass ratio of the weak acid type hydrogen type ion exchange resin to the weak acid type sodium type ion exchange resin is preferably (0.5-1.5)∶1, for example, 0.6∶1, 1∶1 or 1.2∶1.

[0019] In the present application, the particle size of the weak acid type hydrogen type ion exchange resin and the weak acid type sodium type ion exchange resin can independently be 0.3-1.2mm.

[0020] In the present application, the weak acid type sodium type ion exchange resin and the weak acid type hydrogen type ion exchange resin can form a dynamic hydrolysis equilibrium of weak acid strong base salt in water, and the equilibrium process is as follows:

[0021]

[0022] When the pH value of the incoming water is lower than 7, the water is weakly acidic, the above equilibrium moves forward, consumes hydrogen ions in the water, and the pH value of the water slowly rises to above 7, showing weak alkalinity.

[0023] When the pH value of the incoming water is greater than 8, the water is strongly alkaline, the above equilibrium moves reversely, generates hydrogen ions, and the pH value of the water slowly decreases to about 7.

[0024] According to the above equilibrium, when the pH value of the incoming water is 6, the hydrogen ion in the incoming water is only 10 -6mol / L, when the pH value of the water inflow is 7, the hydrogen ion in the water inflow is 10 -7 mol / L, the hydrogen ion is reduced by 9*10 -7 mol / L, the corresponding sodium ion is increased by 9*10 - 7 mol / L. Therefore, when the filter core of the present application is used, a large amount of sodium ion is not exchanged, so that the sodium ion content of the produced water basically does not change too much, and therefore there is no need to worry about the burden on the human body caused by excessive sodium ion.

[0025] In a preferred embodiment of the present application, the acid-base buffer filter core comprises 50% coconut shell activated carbon, 20% weak acid type sodium type ion exchange resin and 30% weak acid type hydrogen type ion exchange resin, and the above percentages are the mass percentages of each component in the acid-base buffer filter core.

[0026] In a preferred embodiment of the present application, the acid-base buffer filter core comprises 50% coconut shell activated carbon, 25% weak acid type sodium type ion exchange resin and 25% weak acid type hydrogen type ion exchange resin, and the above percentages are the mass percentages of each component in the acid-base buffer filter core.

[0027] In a preferred embodiment of the present application, the acid-base buffer filter core comprises 40% coconut shell activated carbon, 40% weak acid type sodium type ion exchange resin and 20% weak acid type hydrogen type ion exchange resin, and the above percentages are the mass percentages of each component in the acid-base buffer filter core.

[0028] In a preferred embodiment of the present application, the acid-base buffer filter core comprises 40% coconut shell activated carbon, 30% weak acid type sodium type ion exchange resin and 30% weak acid type hydrogen type ion exchange resin, and the above percentages are the mass percentages of each component in the acid-base buffer filter core.

[0029] In a preferred embodiment of the present application, the acid-base buffer filter core comprises 60% coconut shell activated carbon, 25% weak acid type sodium type ion exchange resin and 15% weak acid type hydrogen type ion exchange resin, and the above percentages are the mass percentages of each component in the acid-base buffer filter core.

[0030] In a preferred embodiment of the present application, the acid-base buffer filter core comprises 60% coconut shell activated carbon, 20% weak acid type sodium type ion exchange resin and 20% weak acid type hydrogen type ion exchange resin, and the above percentages are the mass percentages of each component in the acid-base buffer filter core.

[0031] The present application also provides a preparation method of the acid-base buffer filter core, which comprises the following steps: mixing the activated carbon, the weak acid type sodium type ion exchange resin and the weak acid type hydrogen type ion exchange resin.

[0032] The application also provides application of the acid-base buffer filter core as a filter material in the fields of food, chemical industry or medicine.

[0033] In the application, the application is preferably application in the field of chemical water purification.

[0034] In the application, when the acid-base buffer filter core is applied to the field of chemical water purification, the water treatment system can sequentially comprise a pretreatment filter core, a nanofiltration filter core or a reverse osmosis filter core, and the acid-base buffer filter core,

[0035] The pretreatment filter core can be a filter core commonly used in the field for removing particulate matter, residual chlorine, organic matter and other substances in water. Preferably, the pretreatment filter core is a PP cotton filter core or an activated carbon filter core.

[0036] The nanofiltration filter core or the reverse osmosis filter core functions to reduce the hardness and alkalinity of water and remove heavy metals, organic matter and other impurities therein.

[0037] Preferably, the water treatment system further comprises an electric valve, which is arranged before the pretreatment filter core.

[0038] Preferably, a booster pump is further arranged between the pretreatment filter core and the nanofiltration filter core or the reverse osmosis filter core.

[0039] On the basis of common sense in the field, the above-mentioned preferred conditions can be combined at will, thereby obtaining preferred examples of the application.

[0040] The reagents and raw materials used in the application are commercially available.

[0041] The positive progress effect of the application is that:

[0042] The filter core of the application constructs a weak acid-strong base salt buffer system by adjusting the proportion of activated carbon, weak acid type hydrogen ion exchange resin and weak acid type sodium ion exchange resin. The water passing through the filter core has no influence on other indicators, and more importantly, the pH value of the water is stably in the range of weak alkaline water (for example, the pH value can be 7.0-7.5 weak alkaline), avoiding excessive acidity or alkalinity, and further improving the drinking experience.

[0043] The filter core of the application can be quickly matched with different water purifiers, is simple and convenient, and has low cost.

[0044] The filter core of the application can be applied after a nanofiltration membrane or a reverse osmosis membrane filter core. In the filtration process, the sodium ions in the filter core are not exchanged, and the sodium ion content of the produced water is basically unchanged, so there is no need to worry about the burden on the human body caused by excessive sodium ions. BRIEF DESCRIPTION OF DRAWINGS

[0045] Figure 1 The figure is a schematic diagram of a water treatment system of the application.

[0046] Reference signs:

[0047] 1-electric valve; 2-pre-treatment filter; 3-boosting pump; 4-reverse osmosis filter; 5-acid-base buffer filter; A-inlet water; B-purified water; C-drainage. DETAILED DESCRIPTION

[0048] The present application is further illustrated by the following examples without limiting the present application to the examples described. The experimental methods in the following examples, unless otherwise specified, are carried out according to the conventional methods and conditions, or according to the commercial instructions.

[0049] The raw materials used in the following examples and comparative examples are as follows:

[0050] The activated carbon is purchased from Yakobi Carbon Industry (Tianjin) Co., Ltd. and the model is Aquasorb JHS-200. The particle size of the activated carbon is 8-30 mesh, the iodine adsorption value is 800-1500 mg / g, the methylene blue adsorption value is ≥9 mL / 0.1 g, the ash content is 8-15%, the wear resistance is 90-98%, and the water content is 3-8%.

[0051] The weak acid type sodium ion exchange resin is purchased from Langsheng Chemical (China) Co., Ltd. and the model is Lewatit S8229plus.

[0052] The weak acid type hydrogen ion exchange resin is purchased from Langsheng Chemical (China) Co., Ltd. and the model is Lewatit S8227.

[0053] Examples 1-8 and Comparative Examples 1-2

[0054] The acid-base buffer filter in Examples 1-8 and Comparative Examples 1-2 comprises: coconut shell activated carbon, weak acid type sodium ion exchange resin, and weak acid type hydrogen ion exchange resin. The specific amount and the pH value of the inlet and outlet water are shown in Table 1.

[0055] The components are mixed uniformly by a conventional method to obtain the acid-base buffer filter.

[0056] In the acid-base buffer filter, the filling amount is 100 g, i.e. the total mass of the coconut shell activated carbon, the weak acid type sodium ion exchange resin, and the weak acid type hydrogen ion exchange resin is 100 g.

[0057] Reference Figure 1The filter core is assembled into a water treatment system. The filter core of the above embodiment or the comparative example is used as an acid-base buffer filter core 5, and is assembled into a water treatment system with a pretreatment filter core 2 and a reverse osmosis filter core 4. In the water treatment system, water A enters the pretreatment filter core 2 through the electric valve 1, and the water is pretreated and then enters the reverse osmosis filter core 4 through the booster pump 3. The waste water produced in the reverse osmosis filter core 4 is discharged as water C, and the water produced by the reverse osmosis filter core 4 (generally with a hardness of less than 100 ppm and a pH value of 5-7) enters the acid-base buffer filter core 5 of the embodiment or the comparative example, and the water produced by the acid-base buffer filter core 5 is the purified water B (with a pH value of 7.0-7.5 and a general hardness of 0 ppm). The pretreatment filter core 2 is a PP cotton and activated carbon filter core, and the main component of the reverse osmosis membrane of the reverse osmosis filter core 4 is polyamide. The flow rate of the water entering the acid-base buffer filter core 5 is 2.5 L / min.

[0058] The filter core of the present application has a high water treatment capacity, and 100 g of the filter core can treat 6 tons of water.

[0059] Table 1: Formulation of the acid-base buffer filter core and pH value of the inlet and outlet water in Examples 1-8 and Comparative Examples 1-2

[0060]

[0061] As can be seen from Comparative Examples 1-2, when one of the weak acid type hydrogen ion exchange resin and the weak acid type sodium ion exchange resin is contained, the pH value of the outlet water is only increased or decreased, and a good and stable acid-base buffer system cannot be constructed.

Claims

1. An acid-base buffer filter element, characterized in that, It includes: 38%-62% activated carbon, 13%-42% weak acid sodium ion exchange resin and 18%-42% weak acid hydrogen ion exchange resin, the above percentages are the mass percentages of each component in the acid-base buffer filter cartridge. The activated carbon has a particle size of 8-30 mesh; the weak acid type hydrogen ion exchange resin and the weak acid type sodium ion exchange resin each have a particle size of 0.3-1.2 mm.

2. The acid-base buffer filter element as described in claim 1, characterized in that, The acid-base buffer filter element meets one or more of the following conditions: a) The amount of activated carbon used is 40%-60%; b) The amount of the weak acid type hydrogen ion exchange resin used is 15%-40%; c) The amount of the weak acid sodium ion exchange resin used is 20%-40%.

3. The acid-base buffer filter element as described in claim 1, characterized in that, The acid-base buffer filter element meets one or more of the following conditions: a) The amount of activated carbon used is 45%, 50%, or 55%; b) The amount of the weak acid type hydrogen ion exchange resin used is 20%, 25%, 30% or 35%; c) The amount of the weak acid sodium ion exchange resin used is 25%, 30%, or 35%.

4. The acid-base buffer filter element as described in claim 1, characterized in that, The mass ratio of the weak acid type hydrogen ion exchange resin to the weak acid type sodium ion exchange resin is (0.5-1.5):

1.

5. The acid-base buffer filter element as described in claim 1, characterized in that, The mass ratio of the weak acid type hydrogen ion exchange resin to the weak acid type sodium ion exchange resin is 0.6:1, 1:1, or 1.2:

1.

6. The acid-base buffer filter element as described in claim 1, characterized in that, The activated carbon satisfies one or more of the following conditions: a) The activated carbon is coal-derived charcoal or coconut shell activated carbon; b) The iodine adsorption value of the activated carbon is 800-1500 mg / g; c) The methylene blue adsorption value of the activated carbon is ≥9 mL / 0.1 g; d) The ash content in the activated carbon is 8-15%; e) The abrasion resistance of the activated carbon is 90-98%; and f) The activated carbon has a moisture content of 3-8%.

7. The acid-base buffer filter element as described in claim 1, characterized in that, The acid-base buffer filter element comprises: 50% coconut shell activated carbon, 20% weak acid sodium ion exchange resin and 30% weak acid hydrogen ion exchange resin. Alternatively, the acid-base buffer filter element comprises: 50% coconut shell activated carbon, 25% weak acid sodium ion exchange resin and 25% weak acid hydrogen ion exchange resin. Alternatively, the acid-base buffer filter element comprises: 40% coconut shell activated carbon, 40% weak acid sodium ion exchange resin and 20% weak acid hydrogen ion exchange resin, wherein the above percentages are the mass percentages of each component in the acid-base buffer filter element. Alternatively, the acid-base buffer filter element comprises: 40% coconut shell activated carbon, 30% weak acid sodium ion exchange resin and 30% weak acid hydrogen ion exchange resin. Alternatively, the acid-base buffer filter element comprises: 60% coconut shell activated carbon, 25% weak acid sodium ion exchange resin and 15% weak acid hydrogen ion exchange resin. Alternatively, the acid-base buffer filter element comprises: 60% coconut shell activated carbon, 20% weakly acidic sodium-type ion exchange resin and 20% weakly acidic hydrogen-type ion exchange resin.

8. The acid-base buffer filter element as described in claim 1, characterized in that, The activated carbon is coconut shell activated carbon.

9. The application of an acid-base buffer filter element as described in any one of claims 1-8 as a filter material in the food, chemical, or pharmaceutical fields.

10. The application as described in claim 9, characterized in that, The application described is in the field of chemical water purification.

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