A kind of extracting method of microalgae grease
Technical field
The present invention relates to a kind of extracting methods of microalgae grease, relate in particular to a kind of using Aqueous phase extraction microalgae oil
The method of rouge.
Background technique
Microalgae is that one kind is grown in water, many kinds of and extremely extensive rudimentary plant of distribution.This kind of biology has
Efficient photosynthesis reaction system, can pass through CO2Fixation, convert light energy into chemical energy, and with grease or starch etc.
The form of organic matter is stored in body cell.As the pressure and environmental problem of human society shortage of resources are increasingly serious, utilize
Microalgae carries out the exploitation of biodiesel and its part fossil energy substitute products, it has also become the hot spot studied at present.
Carrying out production of biodiesel using microalgae is a complicated system engineering, covers multiple sport technique segments, including micro-
The collection and several aspects such as processing of the screening and cultivation of algae algae, the scale evaluation of microalgae and induction Lipid-producing, grease.Microalgae
Research as biodiesel raw material starts from the 1960s, in recent years, with the development of biotechnology, by algae
Biogenic reworking has obtained the microalgae resource abundant with high oil productive capacity, therefore this novel production of biodiesel mode
There is application prospect very much.
For microalgae as a kind of novel biomass energy, advantage is it will be apparent that still at it using upper, from current
From the point of view of progress, it is still in infancy.Current research is concentrated mainly on screening advantage algae, improves oily algae growth by force
Degree increases fat content aspect, and also very to the research of improve grease yield, establish industrialized process for extracting etc.
It is few.However, the research for microalgae, final purpose be to solve the problems, such as alternative energy source towards petrochemical industry, so
The research for exploring grease extractions efficient, suitable for large-scale production and application should become the side of modern the latter period research
To.
The fat content difference of microalgae is very big, between variety classes or even same kind of different lines there is also compared with
Big difference, some algaes for being easy to pilot scale culture, fat content typically constitutes from the 20%~50% of dry cell weight, well below normal
The oil crops of rule, therefore the grease extraction of some classics is not suitable for the extraction of microalgae grease.
CN200810240949.3 discloses a kind of from microalgae while the method for extracting grease and protein, this method are with wet algal gel
Raw material adjusts pH value to alkalinity or alkalescent, the dissolution of the broken wall, grease and protein of microalgae cell is carried out by steam.Institute
It obtains microalgae molten slurry and obtains grease and protein mixture after filtering removes cell residue, then cyclone hydraulic separators is utilized to carry out grease
Separation obtains microalgae grease.Because the specific surface area of microalgae cell is very big, and the phospholipid composition content on cell membrane is very high, because
Although this this method preparation process is simple, due to using the pretreatment mode of filtering, the loss of lubricant component is increased
Rate.CN200910060589.3 discloses the extracting method of a kind of microbial oil and its short-link alcohol fatty acid ester, comprising: adjusts
Moisture: to obtain including the water content containing grease microorganism as 20~90% wet culture;Microwave treatment: to wet culture into
Row microwave radiation breaks born of the same parents and water content is made to be down to 5%~40%;Short chain alcohol processing: partial alcoholysis under the action of basic catalyst
Grease in microbial body, while oil and grease extracting;Recycling design: being separated by solid-liquid separation, and obtains micro- life after short chain alcohol is recycled in evaporation
The mixture of object grease and short-link alcohol fatty acid ester.This method microalgae carry out microwave treatment break born of the same parents after be added short chain alcohol solvent into
Row processing, although the short chain alcohol solvent has certain dissolution to the cell membrane phospholipid layer after broken born of the same parents, the dissolution of its alcohol
Effect is limited, and short chain alcohol mainly participates in base catalyzed reactions.
Summary of the invention
In view of the deficiencies of the prior art, the present invention provides a kind of extracting methods of microalgae grease.The present invention uses water phase
Method extracts microalgae grease, with operating process is simple, microalgae oil yield is high, advantages of environment protection.
The extracting method of microalgae grease of the present invention, includes the following steps:
(1) certain density inorganic salt solution and aqueous slkali agitating and heating are added into the microalgae of collection, utilizes alkali and salt
Synergistic effect make cell wall lysis, broken;
(2) from the aliphatic ester intracellular released continue that saponification occurs with alkali, generate fatty acid salt;
(3) frustule fragment is removed;
(4) inorganic salt solution is continuously added into system, fatty acid salt is precipitated, and solid is collected by filtration;
(5) inorganic acid is added into fatty acid salt, is acidified, obtains free fatty acid, collects product fatty acid.
Microalgae of the present invention may come from any oil-producing microalgae with accumulation grease, fatty acid ability, such as can be with
It is green alga, diatom, red algae etc., especially chlorella or Wild Vitis species.The microalgae of collection can be microalgae powder and be also possible to microalgae mud.
Inorganic salts described in step (1) can be NaNO3、Na2CO3、NaHCO3, sodium ascorbyl phosphate, one in potassium phosphate
Kind, concentration is 0.01 ~ 0.03mol/L.Inorganic salt solution can use the culture solution collected and separated after microalgae with frustule and prepare.
The aqueous slkali can be the NaOH solution or KOH solution that mass concentration is 10% ~ 30%.(quality is with dry weight for the microalgae of collection
Meter) it with the mass volume ratio of inorganic salt solution and aqueous slkali is 1:5 ~ 1:10, the wherein volume ratio of inorganic salt solution and aqueous slkali
For 5:1 ~ 1:1.
Heating temperature described in step (1) can be 50 ~ 70oC, 20 ~ 120min of agitating and heating time.
Step (3) the removing frustule fragment can be using film filtering or centrifugal filtration.
Step (4) inorganic salts are consistent with the middle addition of step (1), can be the unsaturation that concentration is 0.8 ~ 3mol/L
(quality is with dry for the microalgae of the saturated solution of solution either inorganic salts, the preferably saturated solution of inorganic salts, additional amount and collection
Restatement) volume mass ratio be 10:1 ~ 5:1.
Inorganic acid described in step (5) can be one of sulfuric acid, hydrochloric acid, nitric acid, and being acidified to pH is 1 ~ 4, described
Collecting fatty acid can be using the method for centrifugation, and fatty acid is preferably separated with water phase after centrifugation, phase product in collection.
Compared with prior art, the method for the present invention has the advantages that
(1) break process, one side salting liquid are carried out to microalgae cell in such a way that salting liquid and aqueous slkali combine
Addition there is autolysis to microalgae cell, the saponification of another aspect alkali can be such that frustule wall quickly dissolves, add
Under heat and stirring condition, the synergistic effect of salt and alkali can significantly improve the yield of frustule crushing effect and grease.
(2) process being precipitated and then grease is first transformed into salt, grease is water-soluble with other in frustule well
Property larger molecular organics and other impurities separation, by the extraction of grease and purification one step carry out, significantly reduce biodiesel system
The load of pre-processing when standby.
(3) inorganic salts that salting-out process uses are one of micro-algae culture medium nutritive salt, and the liquid separated after saltouing is rich
Containing inorganic nutrient salt, the component that can be used as micro-algae culture medium continues reuse.
The method of the present invention extracts microalgae grease using Aqueous phase, belongs to low energy consumption, environmentally friendly technology path, has simultaneously
There is simple process, is easy to the characteristics of amplifying with grease high income.
Specific embodiment
It is illustrated below with reference to detailed process and effect of the embodiment to hair method of the present invention, but is not limited to following implementation
Example.In the present invention, grease yield=(product fatty acid quality/initial frustule dry weight) × 100%.
Embodiment 1
Microalgae is chlorella (chlorella vulgaris), through 10L bioreactor culture 10 days, at the end of culture
Analyze frustule concentration be 1.82g/L(dry weight meter).It takes 5L microalgae liquid to be centrifuged, controls centrifuge RPMs 4000rpm, centrifugation
Time 3min, obtains microalgae mud.The Na of 0.03mol/L is added into microalgae mud2CO3The sodium hydroxide solution of solution 45ml and 10%
45ml.Above-mentioned system is heated to 60 oC, is stirred simultaneously, 100 min are kept, carries out the saponification of clasmatosis and grease.
It is later 10 with membrane aperture-1μm micro-filtrate membrane filtration, remove frond cell, fragment.1mol/L is continuously added into liquid system
Na2CO3Solution 90ml, is precipitated fatty acid salt, and solid is collected by filtration;Fatty acid salt solid is dissolved in a small amount of water, salt is added
Acid solution is acidified to pH 2.0, obtains free fatty acid;By the system centrifugal treating, phase in collection obtains 3.02g product fatty
Acid, grease yield are 33.2%.
Embodiment 2
Microalgae is Wild Vitis species, through 10L bioreactor culture 10 days, analyzed at the end of culture frustule concentration is
1.78g/L(dry weight meter).It takes 5L microalgae liquid to be centrifuged, controls centrifuge RPMs 4000rpm, centrifugation time 5min obtains microalgae
Microalgae mud drying, milled processed are obtained the micro- algae powder of 8.9g by mud.The NaNO of 0.02mol/L is added into micro- algae powder3Solution
The sodium hydroxide solution 29ml of 58ml and 30%.Above-mentioned system is heated to 70 oC, is stirred simultaneously, 120 min are kept, is carried out thin
The broken saponification with grease of born of the same parents.It is later 10 with membrane aperture-1μm micro-filtrate membrane filtration, remove frond cell, fragment.To liquid
The NaNO of 1.5 mol/L is continuously added in body system3Solution 45ml, is precipitated fatty acid salt, and solid is collected by filtration;By fatty acid
Salt solid is dissolved in a small amount of water, and hydrochloric acid solution is added and is acidified to pH 3.0, obtains free fatty acid;By the system centrifugal treating,
Phase in collection, obtains 3.12g product fatty acid, and grease yield is 35.1%.
Embodiment 3
Microalgae is Wild Vitis species, through 10L bioreactor culture 10 days, analyzed at the end of culture frustule concentration is
1.92g/L(dry weight meter).It takes 5L microalgae liquid to be centrifuged, controls centrifuge RPMs 4000rpm, centrifugation time 5min obtains microalgae
Microalgae mud drying, milled processed are obtained the micro- algae powder of 9.6g by mud.The KH of 0.03mol/L is added into micro- algae powder2PO4Solution
The potassium hydroxide solution 40ml of 40ml and 10%.Above-mentioned system is heated to 50 oC, is stirred simultaneously, 120 min are kept, is carried out thin
The broken saponification with grease of born of the same parents.It is later 10 with membrane aperture-1μm micro-filtrate membrane filtration, remove frond cell, fragment.To liquid
The KH of 1.5mol/L is continuously added in body system2PO4Solution 48ml, is precipitated fatty acid salt, and solid is collected by filtration;By fatty acid
Salt solid is dissolved in a small amount of water, and hydrochloric acid solution is added and is acidified to pH 3.0, obtains free fatty acid;By the system centrifugal treating,
Phase in collection, obtains 3.40g product fatty acid, and grease yield is 35.4%.
Embodiment 4
Microalgae is chlorella, through 10L bioreactor culture 10 days, analyzed at the end of culture frustule concentration is
1.93g/L(dry weight meter).It takes 5L microalgae liquid to be centrifuged, controls centrifuge RPMs 4000rpm, centrifugation time 5min obtains microalgae
Microalgae mud drying, milled processed are obtained the micro- algae powder of 9.65g by mud.The K of 0.01mol/L is added into micro- algae powder2HPO4•
3H2The potassium hydroxide solution 20ml of O solution 50ml and 20%.Above-mentioned system is heated to 50 oC, is stirred simultaneously, keeps 120
Min carries out the saponification of clasmatosis and grease.It is later 10 with membrane aperture-1μm micro-filtrate membrane filtration, remove frond it is thin
Born of the same parents, fragment.The K of 1mol/L is continuously added into liquid system2HPO4••3H2O solution 60ml, is precipitated fatty acid salt, and filtering is received
Collect solid;Fatty acid salt solid is dissolved in a small amount of water, hydrochloric acid solution is added and is acidified to pH 4.0, obtains free fatty acid;It will
The system centrifugal treating, phase in collection obtain 3.16g product fatty acid, and grease yield is 32.7%.
Embodiment 5
Microalgae chlorella, through 10L bioreactor culture 10 days, analyzed at the end of culture frustule concentration is
1.82g/L(dry weight meter).It takes 5L microalgae liquid to be centrifuged, controls centrifuge RPMs 4000rpm, centrifugation time 4min obtains microalgae
Microalgae mud drying, milled processed are obtained the micro- algae powder of 9.1g by mud.The NaH of 0.02mol/L is added into micro- algae powder2PO4Solution
The potassium hydroxide solution 20ml of 60ml and 25%.Above-mentioned system is heated to 50 oC, is stirred simultaneously, 120 min are kept, is carried out thin
The broken saponification with grease of born of the same parents.It is later 10 with membrane aperture-1μm micro-filtrate membrane filtration, remove frond cell, fragment.To liquid
The NaH of 3mol/L is continuously added in body system2PO4Solution 50ml, is precipitated fatty acid salt, and solid is collected by filtration;By fatty acid salt
Solid is dissolved in a small amount of water, and hydrochloric acid solution is added and is acidified to pH 2.5, obtains free fatty acid;By the system centrifugal treating, receive
Phase on collection, obtains 3.10g product fatty acid, and grease yield is 34.1%.
Embodiment 6
Microalgae is diatom, through 10L bioreactor culture 10 days, analyzed at the end of culture frustule concentration is
1.66g/L(dry weight meter).It takes 5L microalgae liquid to be centrifuged, controls centrifuge RPMs 4000rpm, centrifugation time 3min obtains microalgae
Mud.The Na of 0.03 mol/L is added into microalgae mud2CO3The sodium hydroxide solution 10ml of solution 40ml and 10%.By above-mentioned system
It is heated to 60oC, is stirred simultaneously, 100min is kept, carries out the saponification of clasmatosis and grease.It is later 10 with membrane aperture-1
μm micro-filtrate membrane filtration, remove frond cell, fragment.The Na of 1.5mol/L is continuously added into liquid system2CO3Solution 83ml,
Fatty acid salt is precipitated, solid is collected by filtration;Fatty acid salt solid is dissolved in a small amount of water, hydrochloric acid solution is added and is acidified to pH
2.0, obtain free fatty acid;By the system centrifugal treating, phase in collection obtains 2.47g product fatty acid, and grease yield is
29.8%。
Embodiment 7
Microalgae is Wild Vitis species, through 10L bioreactor culture 10 days, analyzed at the end of culture frustule concentration is
2.08g/L(dry weight meter).It takes 5L microalgae liquid to be centrifuged, controls centrifuge RPMs 4000rpm, centrifugation time 3min obtains microalgae
Mud.The NaHCO of 0.02 mol/L is added into microalgae mud3The sodium hydroxide solution 25ml of solution 75ml and 15%.By above-mentioned system
60 oC are heated to, are stirred simultaneously, 100 min are kept, carry out the saponification of clasmatosis and grease.It is with membrane aperture later
10-1μm micro-filtrate membrane filtration, remove frond cell, fragment.The NaHCO of 0.8mol/L is continuously added into liquid system3Solution
Fatty acid salt is precipitated in 100ml, and solid is collected by filtration;Fatty acid salt solid is dissolved in a small amount of water, hydrochloric acid solution acidification is added
To pH 2.0, free fatty acid is obtained;By the system centrifugal treating, phase in collection obtains 3.15g product fatty acid, and grease is received
Rate is 30.3%.
Embodiment 8
Na is added into liquid system after film filtering2CO3Saturated solution 90ml, is precipitated fatty acid salt.Other conditions are the same as real
Apply example 1.3.32g product fatty acid is obtained, grease yield is 36.5%.
Embodiment 9
NaNO is added into liquid system after film filtering3Saturated solution 45ml, is precipitated fatty acid salt.Other conditions are the same as real
Apply example 2.3.35g product fatty acid is obtained, grease yield is 37.6%.
Comparative example 1
In microalgae cell shattering process, 10% sodium hydroxide solution 90ml is only added into microalgae mud, and is added without salt
Solution, remaining is the same as embodiment 1.2.35g fatty acid is obtained, grease yield is 25.8%.
Comparative example 2
In microalgae cell shattering process, 30% sodium hydroxide solution 90ml is only added into micro- algae powder, and is added without
Salting liquid, remaining is the same as embodiment 2.2.11g fatty acid is obtained, grease yield is 23.7%.