CN109821274A - The method of heavy metal in amino modified silica gel material removing water-soluble tea extract - Google Patents
The method of heavy metal in amino modified silica gel material removing water-soluble tea extract Download PDFInfo
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- CN109821274A CN109821274A CN201910191931.7A CN201910191931A CN109821274A CN 109821274 A CN109821274 A CN 109821274A CN 201910191931 A CN201910191931 A CN 201910191931A CN 109821274 A CN109821274 A CN 109821274A
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- heavy metal
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Abstract
The invention discloses amino modified silica gel material removing water-soluble tea extract in heavy metal method, the method includes prepare tea extraction aqueous solution, prepare amino modified silica gel adsorption column, cross column processing and adsorption column recycling and etc..The method of heavy metal can rapidly, continuously remove the heavy metals such as lead, copper, cadmium, chromium in water-soluble tea extract in amino modified silica gel material removing water-soluble tea extract of the present invention, and adsorption column is small to the adsorptivity of water-soluble tea extract, therefore it is lost also smaller, reach and 95% is greater than to the removal efficiency of the heavy metals such as lead, copper, cadmium, chromium, the loss late of water-soluble tea extract is less than 5%；It in addition, adsorption column prepared by the present invention can be reused after the heavy metal for removing absorption by the elution of edta salt solution, therefore can be advantageously applied in tea comprehensive processing technique, have a extensive future.
Description
Technical field
The invention belongs to food green processing technique fields, are related to a kind of method for removing heavy metal in tea extraction, tool
Body is the method that amino modified silica gel material removes heavy metal in water-soluble tea extract.
Background technique
Heavy metal be it is a kind of not biodegradable, easily absorbed by organism and be enriched with and have very highly toxic dirt to organism
Contaminate object.Chemistry manufacture, digs up mine, and the industrial wastewater generated in the industrial activities such as metallurgy contains plurality of heavy metal, to soil and farming
Object causes serious pollution, if the cadmium content in rice is exceeded, lead in corn, and the enrichment of cadmium and zinc, nickel, chromium in soybean,
Copper and lead it is exceeded, in tealeaves, the residual of the heavy metals such as lead, arsenic, cadmium, copper, chromium, nickel.Heavy metal pollution not only causes largely
Economic loss, while huge threat also is constituted to human health.
Water-soluble tea extract such as tea polyphenols, theanine, tea polysaccharide etc. is the main deep processing product of tealeaves, is had anti-
The physiological functions such as oxidation, hypoglycemic, reducing blood lipid, thus nutritive value with higher and vast market prospect.But in tealeaves
Plantation, the pollution processed, heavy metal can be generated in storage process.Currently, the removing sulfuldioxide of heavy metal in waste water is more mature,
It mainly include (Fu F., the Wang Q.Removal of heavy metal such as precipitating, filtering, ion exchange, reverse osmosis, absorption
ions from wastewaters:a review[J].J Environ Manage,2011,92(3):407-418.)；Wherein,
Adsorption technology because its with flexible operation, low energy consumption, the selectivity advantages such as high, low in cost, adsorbent Reversible Regeneration due to by
Extensive concern (Hua M., Zhang S., Pan B., et al.Heavy metal removal from water/
wastewater by nanosized metal oxides:a review[J].J Hazard Mater,2012,211-212:
317-331.Paulino A.T.,Belfiore L.A.,Kubota L.T.,et al.Effect of magnetite on
the adsorption behavior of Pb(II),Cd(II),and Cu(II)in chitosan-based
hydrogels[J].Desalination,2011,275(1-3):187-196.)。
With soil, water source, ecological environmental pollution is got worse, and the pollution of heavy metal is also impossible to guard against in food,
Therefore how heavy metal under the premise of not destroying food original ingredient in removing food has become the words of a hot spot instantly
Topic.Zou[4]Et al. researches show that citric acid significantly reduce rice bran in cadmium content while will not be to the γ-Gu Wei in rice
Cellulose content, tocopherol content and fatty acid composition significantly affect (Zou Y., Zhang C., Ju X., et al.Effect
of removing cadmium with citric acid on the physicochemical and
microstructure properties of rice bran[J].Food Control, 2019,98:290-296.)。
Shen[5]Et al. researches show that P123-DA hydrogel efficiently removal milk in Pb2+And Hg2+While will not destroy ox
Milk nutritional ingredient (Shen C., Peng B., Wang Y., et al.Pb (2+) and Hg (2+) removal from
polluted milk by di-acrylated Pluronic P123hydrogels[J].Food Chem,2018,258:
331-336.).Currently, having the method that heavy metal is removed in some pairs of millet paste and instant tea, patent CN106900923A
A kind of method for reducing heavy metal in instant tea is disclosed, specially adsorbent material is all placed in solution and is stirred 1-7
Its absorption heavy metal, then removes remaining adsorbent material using filter-cloth filtering again.Therefore, there is the processing time in the prior art
Longer deficiency, and treated that solution can not continue that recycling uses.In addition, patent CN104642614A discloses a kind of reduction speed
The method of the heavy metal ion contents such as arsenic, lead in molten tea, the patent is using the huge sum of money in large pore resin absorption column removing instant tea
Belong to, the prior art the method may be implemented in instant tea content of beary metal decline 50%, and polyphenol content detraction 5% with
Under.
Summary of the invention
The technical issues of solution: for overcome the deficiencies in the prior art, obtaining one kind being capable of efficient removal tea extraction water
Heavy metal in solution, tea polyphenols loss is small, and the method that adsorption column may be reused, and the present invention provides amino modified silicon
The method that glue material removes heavy metal in water-soluble tea extract.
Technical solution: the method for heavy metal, the method packet in amino modified silica gel material removing water-soluble tea extract
Include following steps:
Step 1 prepares tea extraction aqueous solution
Tea extract or water-soluble tea extract are configured to the aqueous solution of 1-60wt%, adjusting pH is 3-7, is used in combination
0.45 μm of membrane filtration removes insoluble solid, collects filtered fluid, spare；
Step 2 prepares amino modified silica gel adsorption column
By the silica gel 1-10g of 50-600 mesh and 10-100mL dry toluene in three-neck flask, magnetic force under nitrogen protection
50-500rpm is stirred, and 1-20mL 3- aminopropyl triethoxysilane (APTS) is added dropwise, then by mixture in 50-
150 DEG C are heated to reflux 4-36h, and final solid product is obtained by filtration, and are successively washed with toluene, acetone, ether and methanol, then
Dry 2-24h, can be obtained amino modified silica gel at 50-120 DEG C；
After the above-mentioned addition 1-5mL ultrapure water mixing by modified silica-gel of 100-1000mg, it is packed into the SPE pillar for containing lower sieve plate
In, it is pressed into upper sieve plate after all silica gel are fully enclosed, prepares amino modified silica gel adsorption column；
Step 3 crosses column
The filtrate of step 1 preparation is adjusted as made from step 2 with the amino modified silica gel adsorption column of upper and lower sieve plate
For flow velocity to keep flow velocity to cross column liquid 1-90min in every column volume, absorption column temperature is 25-50 DEG C, then uses 1-10 times of cylinder
Long-pending volume fraction be 50-100% ethanol solution the tea extraction remained in adsorption column is eluted, collected column liquid and
After eluent concentration, drying, the loss late of water-soluble tea extract is greater than 95% less than 5%, to the removal efficiency of heavy metal；
Step 4, recycling
The adsorption column that heavy metal is adsorbed in step 3 is passed through to the 0.01-1M edta salt solution of 1-20 times of column volume, control
Flow velocity processed crosses column liquid 5-50min in every column volume, and in adsorption column 95% or more heavy metal is eluted, and makes adsorption column circulation
With.
Preferably, tea extraction includes the extracting solution or tea polyphenols of Camellia sinensis plant leaf blade, theanine, tea polysaccharide,
Theaflavin.
Preferably, the weight percentage of tea extract or water-soluble tea extract aqueous solution is 40wt% in step 1.
Preferably, the pH of tea extract or water-soluble tea extract aqueous solution is 4 in step 1.
Preferably, wet method dress post is used in step 2.
Preferably, it is 10mL/min that column flow rate is crossed in step 3.
Preferably, the volume fraction of ethanol solution is 80% in step 3.
Preferably, edta salt is EDETATE SODIUM, dipotassium EDTA, tetra- sodium of EDTA, tetra- potassium of EDTA or ties containing EDTA in step 4
Other water soluble compounds of structure.
Preferably, the concentration of edta salt is 0.02M in step 4.
Preferably, after adsorption column is recycled 6 times, 96% or more is reached to the adsorption rate of heavy metal.
The working principle of the method for heavy metal in amino modified silica gel material removing water-soluble tea extract of the present invention
It is: the APTS compound with amino group is grafted on by Silica Surface by chemical modification, makes its shape between heavy metal
It is combined at ionic bond or coordinate bond, and there is no suction-operated to tea polyphenols, therefore there is good removing ability to heavy metal.
In addition, the amino modified silicagel column for being adsorbed with heavy metal is eluted by eluant, eluent edta salt solution, edta salt solution passes through a huge sum of money
The characteristic for belonging to chelating, elutes the heavy metal in adsorption column, therefore adsorption column can be reused again, has good repetition
Property.
The utility model has the advantages that amino modified silica gel material of the present invention removes the method energy of heavy metal in water-soluble tea extract
The heavy metals such as enough lead, copper, cadmium, the chromium rapidly, continuously removed in water-soluble tea extract, and adsorption column mentions water soluble tea
It takes the adsorptivity of object small, therefore it is lost also smaller, reach and 95% is greater than to the removal efficiencies of the heavy metals such as lead, copper, cadmium, chromium,
The loss late of water-soluble tea extract is less than 5%；In addition, adsorption column prepared by the present invention is removed by the elution of edta salt solution
It can reuse, therefore can be advantageously applied in tea comprehensive processing technique after the heavy metal of absorption, be had a extensive future.
Detailed description of the invention
Fig. 1 is the technical modelling figure of the method for the invention.
Specific embodiment
Following embodiment further illustrates the contents of the present invention, but should not be construed as limiting the invention.Without departing substantially from
In the case where spirit of that invention and essence, to modification made by the method for the present invention, step or condition and replaces, belong to the present invention
Range.Unless otherwise specified, the conventional means that technological means used in embodiment is well known to those skilled in the art.
The removing of heavy metal in 1 tea polyphenols aqueous solution of embodiment
A kind of method for removing heavy metal in tea polyphenols aqueous solution is present embodiments provided, which is always divided into 4
Column absorption and adsorption column recycling are crossed in step, the respectively preparation and pretreatment of tea polyphenols aqueous solution, the preparation of silicagel column.Specifically
Operating method is as follows:
1) preparation and pretreatment of tea polyphenols aqueous solution are weighed in 200g tea polyphenols solid and 500mL ultra-pure water solution,
It is prepared into 40% tea polyphenols solution, adjusting pH value of solution is 4, then by spare after 0.45 μm of filtering.
2) preparation of silicagel column is specifically by 10g amino functional silica gel and 20mL ultrapure water wet method dress post after mixing evenly
(2 × 20cm of rule), column volume is about 90mL.
3) then by peristaltic pump by above-mentioned steps 1) in tea polyphenols aqueous solution be pumped into it is above-mentioned 2) in preparation amino function
It can change in silica gel adsorption column, adjust flow velocity 10mL/min, after being adsorbed to 500mL tea polyphenols solution, with 90mL80% ethyl alcohol
Elution remains in the tea polyphenols in adsorption column, merges concentration, drying after adsorption liquid.Heavy metal contains in tea polyphenols after detection absorption
Amount, as a result shown in following table:
| Heavy metal | Testing result/ppb |
| Pb | <1 |
| Cu | <5 |
| Cd | <1 |
| Cr | It is not detected |
Display reaches 98% or more to the removal efficiency of lead, copper, cadmium, chromium, and the loss of tea polyphenols is less than 2%.
4) using 100mL 0.02M EDETATE SODIUM solution to it is above-mentioned 3) in adsorption column elute, merge eluent
Heavy metal is detected afterwards, testing result shows that the heavy metal for being adsorbed in adsorption column 98% is eluted liquid elution.
5) circulation absorption it is above-mentioned 1) in tea polyphenols aqueous solution 6 times after, to the adsorption rate of the heavy metals such as lead, copper, cadmium, chromium
Still reach 96% or more.
The removing of heavy metal in 2 theanine aqueous solution of embodiment
A kind of method for removing heavy metal in theanine aqueous solution is present embodiments provided, the removal methods concrete operations are such as
Under:
1) preparation and pretreatment of theanine aqueous solution are weighed in 50g theanine solid and 500mL ultra-pure water solution, system
Standby in 10% theanine solution, adjusting pH value of solution is 5.5, then by spare after 0.45 μm of filtering.
2) preparation of silicagel column is specifically that wet method dress post (is advised after mixing evenly with 10mL ultrapure water by 5g amino functional silica gel
Then 2 × 20cm), column volume is about 45mL.
3) then by peristaltic pump by above-mentioned steps 1) in theanine aqueous solution be pumped into it is above-mentioned 2) in preparation amino function
It can change in silica gel adsorption column, adjust flow velocity 10mL/min, after being adsorbed to 500mL theanine solution, with 150mL's 50%
Ethanol elution remains in the theanine in adsorption column, is concentrated after merging adsorption liquid, detects the content of theanine and heavy metal, as a result
Display reaches 97% or more to the removal efficiency of lead, copper, cadmium, chromium, and the loss of theanine is less than 3%.
4) using 50mL 0.1M EDETATE SODIUM solution to it is above-mentioned 3) in adsorption column elute, merge eluent after
Heavy metal is detected, testing result shows that the heavy metal for being adsorbed in adsorption column 95% is eluted liquid elution.
5) circulation absorption it is above-mentioned 1) in theanine aqueous solution 6 times after, to lead, copper, cadmium, chromium heavy metal adsorption rate still
So reach 97.5% or more.
The removing of heavy metal in 3 instant tea of embodiment
The present invention also provides a kind of methods of heavy metal in removing tealeaves Aqueous extracts, and the removal methods concrete operations are such as
Under:
1) preparation and pretreatment of instant tea aqueous solution are weighed in 300g instant tea powder and 500mL ultra-pure water solution,
It is prepared into 60% instant tea solution, adjusting pH value of solution is 5, then by spare after 0.45 μm of filtering.
2) preparation of silicagel column is specifically that wet method dress post (is advised after mixing evenly with 10mL ultrapure water by 5g amino functional silica gel
Then 2 × 20cm), column volume is about 45mL.
3) then by peristaltic pump by above-mentioned steps 1) in instant tea aqueous solution be pumped into it is above-mentioned 2) in preparation amino function
It can change in silica gel adsorption column, adjust flow velocity 10mL/min, after being adsorbed to 500mL instant tea solution, with 150mL's 50%
Ethanol elution remains in the tea polyphenols in adsorption column, merges concentration, drying after adsorption liquid.Detection instant tea and heavy metal contain
Amount, reaches 97% or more to the removal efficiency of lead, copper, cadmium, chromium as the result is shown, the loss of instant tea is less than 5%.
4) using 10mL 0.05M EDETATE SODIUM solution to it is above-mentioned 3) in adsorption column elute, merge eluent after
Heavy metal is detected, testing result shows that the heavy metal for being adsorbed in adsorption column 95% is eluted liquid elution.
5) circulation absorption it is above-mentioned 1) in instant tea aqueous solution 6 times after, to lead, copper, cadmium, chromium heavy metal adsorption rate still
So reach 95% or more.
Claims (10)
1. the method for heavy metal in amino modified silica gel material removing water-soluble tea extract, which is characterized in that the method packet
Include following steps:
Step 1 prepares tea extraction aqueous solution
Tea extract or water-soluble tea extract are configured to the aqueous solution of 1-60wt%, adjusting pH is 3-7, and with 0.45 μm
Membrane filtration removes insoluble solid, collects filtered fluid, spare；
Step 2 prepares amino modified silica gel adsorption column
By the silica gel 1-10g of 50-600 mesh and 10-100mL dry toluene in three-neck flask, magnetic agitation under nitrogen protection
50-500rpm, and 1-20mL 3- aminopropyl triethoxysilane is added dropwise, then mixture is heated back at 50-150 DEG C
4-36h is flowed, final solid product is obtained by filtration, is successively washed with toluene, acetone, ether and methanol, then at 50-120 DEG C
Lower dry 2-24h, can be obtained amino modified silica gel；
After the above-mentioned addition 1-5mL ultrapure water mixing by modified silica-gel of 100-1000mg, it is fitted into the SPE pillar containing lower sieve plate,
It is pressed into upper sieve plate after all silica gel are fully enclosed, prepares amino modified silica gel adsorption column；
Step 3 crosses column
The filtrate of step 1 preparation is adjusted into flow velocity with the amino modified silica gel adsorption column of upper and lower sieve plate as made from step 2
To keep flow velocity to cross column liquid 1-90min in every column volume, absorption column temperature is 25-50 DEG C, then uses 1-10 times of column volume
Volume fraction is that 50-100% ethanol solution elutes the tea extraction remained in adsorption column, collects column liquid and elution
After liquid concentration, drying, the loss late of water-soluble tea extract is greater than 95% less than 5%, to the removal efficiency of heavy metal；
Step 4, recycling
The adsorption column that heavy metal is adsorbed in step 3 is passed through to the 0.01-1M edta salt solution of 1-20 times of column volume, control stream
Speed crosses column liquid 5-50min in every column volume, and in adsorption column 95% or more heavy metal is eluted, adsorption column is recycled.
2. the method for heavy metal in amino modified silica gel material removing water-soluble tea extract according to claim 1,
It is characterized in that, tea extraction includes the extracting solution or tea polyphenols of Camellia sinensis plant leaf blade, and theanine, tea polysaccharide, tea are yellow
Element.
3. the method for heavy metal in amino modified silica gel material removing water-soluble tea extract according to claim 1,
It is characterized in that, the weight percentage of tea extract or water-soluble tea extract aqueous solution is 40wt% in step 1.
4. the method for heavy metal in amino modified silica gel material removing water-soluble tea extract according to claim 1,
It is characterized in that, the pH of tea extract or water-soluble tea extract aqueous solution is 4 in step 1.
5. the method for heavy metal in amino modified silica gel material removing water-soluble tea extract according to claim 1,
It is characterized in that, wet method dress post is used in step 2.
6. the method for heavy metal in amino modified silica gel material removing water-soluble tea extract according to claim 1,
It is characterized in that, it is 10mL/min that column flow rate is crossed in step 3.
7. the method for heavy metal in amino modified silica gel material removing water-soluble tea extract according to claim 1,
It is characterized in that, the volume fraction of ethanol solution is 80% in step 3.
8. the method for heavy metal in amino modified silica gel material removing water-soluble tea extract according to claim 1,
It is characterized in that, edta salt is EDETATE SODIUM, dipotassium EDTA, tetra- sodium of EDTA, tetra- potassium of EDTA or its containing EDTA structure in step 4
Its water soluble compound.
9. the method for heavy metal in amino modified silica gel material removing water-soluble tea extract according to claim 1,
It is characterized in that, the concentration of edta salt is 0.02M in step 4.
10. the method for heavy metal in amino modified silica gel material removing water-soluble tea extract according to claim 1,
It is characterized in that, after adsorption column is recycled 6 times, 96% or more is reached to the adsorption rate of heavy metal.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110252260A (en) * | 2019-06-26 | 2019-09-20 | 济南鸿泰华丰机械有限公司 | A kind of efficient restorative procedure of soil |
| CN112574047A (en) * | 2020-12-25 | 2021-03-30 | 湖州展望药业有限公司 | Production process of low-lead bulk drug esmolol hydrochloride |
| CN113575685A (en) * | 2021-07-30 | 2021-11-02 | 江南大学 | Fish oil composition added to infant formula milk powder |
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2019
- 2019-03-14 CN CN201910191931.7A patent/CN109821274B/en active Active
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110252260A (en) * | 2019-06-26 | 2019-09-20 | 济南鸿泰华丰机械有限公司 | A kind of efficient restorative procedure of soil |
| CN112574047A (en) * | 2020-12-25 | 2021-03-30 | 湖州展望药业有限公司 | Production process of low-lead bulk drug esmolol hydrochloride |
| CN113575685A (en) * | 2021-07-30 | 2021-11-02 | 江南大学 | Fish oil composition added to infant formula milk powder |
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