Background technology
Tellurian biology can be divided into animal, plant and microorganism three major types, and corresponding grease can be divided into animal grease, Vegetable oil lipoprotein and microbial oil.Certain micro-organisms produces in cell and stores under the certain culture condition and accounts for the grease of its biological total amount more than 20%, and this class bacterial strain is called oleaginous microorganism.Grease extracting method by routine can extract the intracellular grease of oleaginous microorganism, obtains microbial bacteria oil.The same with the animal and plant grease, the main component of microbial oil is a chain fatty acid triglycerides.
Biofuel is meant the long-chain fat acid monoester that is obtained through over-churning and transesterification by reproducible glyceride stock, is a kind ofly can substitute the environment friendly fuel that ordinary diesel oil is used.At present, the preparation technology of ester-interchange method production biofuel is a raw material with the animal and plant grease normally, with low-carbon alcohol such as methyl alcohol or ethanol as the transesterify agent, with alkaline matters such as sodium hydroxide, potassium hydroxide as catalyzer, carry out transesterification, generate corresponding fatty acid methyl ester or ethyl ester, be drying to obtain biofuel through washing again.Base catalysis transesterification metallization processes requires grease is carried out pre-treatment usually, has increased process cost.The biodiesel manufacture cost is raw materials cost more than 70% according to statistics.Therefore, utilize cheap raw material, simplify production process technology, to improve transformation efficiency most important to reducing the biofuel cost.
Aforementioned ester-interchange method production of biodiesel technology is with animal and plant grease or waste grease, is raw material as rapeseed oil, soybean oil, Semen Maydis oil, Oleum Gossypii semen, peanut oil, Oleum Helianthi, plam oil, Oleum Cocois, recovery culinary art oil and animal tallow etc.German Patent (DE 19838011) has been mentioned and extracted microbial bacteria oil in produce oil yeast C.curvatus, prepares the technology of biofuel again through chemical conversion.It is the technology of raw material production biofuel with the vegetable seed directly that world patent (WO 2005/030911) has been mentioned.Above method is core technology with the base catalysis all, and not mentioning is raw material with grease-contained oil-containing microbial cells directly, directly prepares biofuel through the acid catalysis transesterification.
Summary of the invention
The object of the present invention is to provide a kind of preparation method of biofuel; The present invention directly carries out transesterification with the oil-containing microbial cells, can substitute with the grease that extracts is the transesterification that raw material carries out, it has not had to extract greasy technological process from raw material, therefore reduced process cost, shortened technology, for the preparation of biofuel provides a kind of new raw material sources, and provide a kind of and directly from the oil-containing raw material, prepared method of bio-diesel oil.
For achieving the above object, the technical solution used in the present invention is:
A kind of preparation method of biofuel by reacting under acid as catalyst with oil-containing microbial cells and low-carbon alcohol, generates fatty acid methyl ester or ethyl ester.
Being specially, is raw material with the oil-containing microbial cells, as the transesterify agent, as catalyzer, behind transesterification, after reaction mixture cooling, filtration, liquid phase are purified, obtains biofuel with mineral acid with low-carbon alcohol (methyl alcohol or ethanol).
The concrete operations condition is,
1) be raw material with the oil-containing microbial cells;
2) add methyl alcohol or ethanol in the raw material as the transesterify agent, consumption is 8~40 times of thalline quality;
3) aforementioned operation 2) add sulfuric acid or hydrochloric acid in the suspension liquid that forms as catalyzer, the amount concentration of catalyst substance reaches 0.1M~1.0M;
4) the transesterification condition is: under the effect of mixing, in 50 ℃~70 ℃ back flow reaction 10 hours~20 hours.
After described transesterification finished, reaction mixture through cooling, filtration, the liquid phase process that obtains biofuel of purifying was,
1) liquid phase is collected in reaction mixture cooling, filtration, and distillation concentrates, and reclaims methyl alcohol or alcohol solvent;
2) in enriched material, add respectively with the isopyknic extraction agent of transesterify agent and with the isopyknic distilled water of transesterify agent; Fully water is removed in vibration behind the standing demix;
3) add and the isopyknic distilled water of transesterify agent, the back layering is left standstill in fully vibration, removes water again; 1-2 time so repeatedly;
4) extraction agent is reclaimed in organic phase distillation, obtains faint yellow, clarification, transparent liquid product, i.e. biofuel.
Described extraction agent can be lower boiling organic solvent such as sherwood oil, hexane or solvent for extraction.
Specific operation process is: the dry bacterial powder of 0.5 gram~2.0 gram oil-containing microbial cells is placed 100 ml flasks; Add 10 milliliters~40 milliliters of acid~methyl alcohol that the concentration prepare in advance is 0.1~1.0M or ethanolic solns immediately, under the effect of mixing, in 50 ℃~70 ℃ back flow reaction 10 hours~20 hours; After question response was complete, cooling was filtered, and collects liquid phase, concentrates removal unreacted methanol or ethanol, adds the sherwood oil and the distilled water of 10~40 milliliters of equivalent respectively, and fully water is removed in vibration behind the standing demix; Add 10 milliliters~40 ml distilled waters again, the back layering is left standstill in fully vibration, removes water; 1~2 time so repeatedly; Dewater with anhydrous sodium sulphate, after filtering, sherwood oil is reclaimed in distillation, and high boiling liquid is in 80 ℃~105 ℃ bakings 1~2 hour, obtains faint yellow, clarification, transparent liquid product, i.e. biofuel.The biodiesel production rate of method acquisition can reach more than 80% of theoretical yield thus.
Advantage of the present invention is:
1. utilize the present invention to extract, both shortened technology, reduced running cost again grease in the oil-containing microbial cells.
2. utilize the present invention not only to expand the raw material of preparation biofuel, and provide a kind of and directly from the oil-containing raw material, prepare method of bio-diesel oil,, can obtain biofuel by the present invention at oil-containing microorganism not of the same race.
3. the present invention is by reacting under acid as catalyst with oil-containing microbial cells and low-carbon alcohol, generate fatty acid monoester, after filtration, washing and organic solvent extraction promptly obtain faint yellow, clarification, transparent liquid product---biofuel, productive rate reaches more than 80%; For the preparation of biofuel provides a kind of new raw material sources and simple and convenient process for preparing.
Embodiment
Be the specific embodiment for preparing biofuel by the oil-containing microbial cells below, can recognize the influence of different technology conditions biodiesel production rate by embodiment.
Embodiment 1
With fat content is that 50% saccharomyces oleaginosus bacterium (Lipomyces starkeyi AS 2.1560 is available from Chinese common micro-organisms culture presevation administrative center) dry bacterial powder 1.0 grams place 100 ml flasks; Adding the concentration for preparing in advance respectively is the H of 0.1M and 1.0M
2SO
420 milliliters of~methanol solutions are under the effect of mixing, in 70 ℃ of back flow reaction 20 hours; After question response was complete, cooling, filtration were collected liquid phase, the distillation for removing methanol solvent; Add 20 milliliters of sherwood oils and 20 ml distilled waters, the back layering is left standstill in fully vibration, removes water; Add 20 ml distilled waters again, the back layering is left standstill in fully vibration, removes water; Sherwood oil dewaters with anhydrous sodium sulphate, and after filtering, sherwood oil is reclaimed in distillation, and residuum is in 105 ℃ of baking 1h, obtains faint yellow, clarification, transparent liquid product, i.e. biofuel.Productive rate is respectively 93.4% and 89.8%.
Embodiment 2
With fat content is that 50% saccharomyces oleaginosus bacterium (Lipomyces starkeyi) dry bacterial powder, 1.0 grams place 100 ml flasks; Adding the concentration for preparing in advance immediately is the H of 0.2M
2SO
420 milliliters of~methanol solutions are under the effect of mixing, in 70 ℃ of back flow reaction 10 hours; Other processing condition are identical with embodiment 1.Productive rate is 79.5%.
Embodiment 3
With fat content is that 50% saccharomyces oleaginosus bacterium (Lipomyces starkeyi) and fat content are that each 1.0 gram of saccharomyces oleaginosus bacterium (Rhodosporidium toruloides) dry bacterial powder of 58% place 100 ml flasks; Add the concentration prepare in advance immediately and be 20 milliliters of HCl~methanol solutions of 0.4M, under the effect of mixing, in 70 ℃ of back flow reaction 20 hours; Other processing condition are identical with embodiment 1.Productive rate is respectively 93.0% and 98.9%.
Embodiment 4
With fat content is that 55.7% saccharomyces oleaginosus bacterium (Lipomyces starkeyi) dry bacterial powder, 1.0 grams place 100 ml flasks; Adding the concentration for preparing in advance immediately is the H of 0.2M
2SO
420 milliliters of~ethanolic solns are under the effect of mixing, in 70 ℃ of back flow reaction 20 hours; Other processing condition are identical with embodiment 1.Productive rate is 98.0%.
Embodiment 5
With oil-containing microorganism not of the same race (Lipomyces starkeyi, Rhodosporidium toruloides, Mortierella isabellina), each 1.0 gram of dry bacterial powder place 100 ml flasks; Add 20 milliliters of the acid~methanol solutions prepare in advance respectively, under the effect of mixing, in 70 ℃ of back flow reaction 20 hours; Other processing condition are identical with embodiment 1.The results are shown in Table 1.
The different oil-containing microorganisms of table 1 prepare biodiesel production rate relatively
The oil-containing microorganism strains | Reaction system | Fat content/% | Bacterium powder/g | Productive rate/% |
Lipomyces starkeyi | 0.2M H
2SO
4-MeOH
| 50.0 | 1.1 | 84 |
Rhodosporidium toruloides | 0.2M H
2SO
4-MeOH
| 58.0 | 1.0 | 98.1 |
Mortierella isabellina | 0.4M HCl-MeOH | 53.2 | 1.0 | 93.2 |
Embodiment 6
With fat content is that 50% oil-containing microorganism (Lipomyces starkeyi), 1.0 gram dry bacterial powders place 100 ml flasks; Adding the concentration for preparing in advance immediately is the H of 0.2M
2SO
420 milliliters of~methanol solutions are under the effect of mixing, in 50 ℃ of back flow reaction 20 hours; Other processing condition are identical with embodiment 1, and obtaining biodiesel production rate is 86.8%.