WO2009074307A2 - Purification de biodiesel par de l'allophane et/ou de l'imogolite - Google Patents

Purification de biodiesel par de l'allophane et/ou de l'imogolite Download PDF

Info

Publication number
WO2009074307A2
WO2009074307A2 PCT/EP2008/010481 EP2008010481W WO2009074307A2 WO 2009074307 A2 WO2009074307 A2 WO 2009074307A2 EP 2008010481 W EP2008010481 W EP 2008010481W WO 2009074307 A2 WO2009074307 A2 WO 2009074307A2
Authority
WO
WIPO (PCT)
Prior art keywords
biodiesel
adsorbent
allophane
crude
glycerol
Prior art date
Application number
PCT/EP2008/010481
Other languages
German (de)
English (en)
Other versions
WO2009074307A3 (fr
Inventor
Ulrich Sohling
Friedrich Ruf
Rosalina Condemarin
Stephan Kaufhold
Original Assignee
Süd-Chemie AG
Bundesrepublik Deutschland Vertreten Durch Den Präsidenten Der Bundesanstalt Für Geowissenschaften Und Rohstoffe
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Süd-Chemie AG, Bundesrepublik Deutschland Vertreten Durch Den Präsidenten Der Bundesanstalt Für Geowissenschaften Und Rohstoffe filed Critical Süd-Chemie AG
Publication of WO2009074307A2 publication Critical patent/WO2009074307A2/fr
Publication of WO2009074307A3 publication Critical patent/WO2009074307A3/fr

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C67/00—Preparation of carboxylic acid esters
    • C07C67/48—Separation; Purification; Stabilisation; Use of additives
    • C07C67/56—Separation; Purification; Stabilisation; Use of additives by solid-liquid treatment; by chemisorption
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G, C10K; LIQUEFIED PETROLEUM GAS; ADDING MATERIALS TO FUELS OR FIRES TO REDUCE SMOKE OR UNDESIRABLE DEPOSITS OR TO FACILITATE SOOT REMOVAL; FIRELIGHTERS
    • C10L1/00—Liquid carbonaceous fuels
    • C10L1/02—Liquid carbonaceous fuels essentially based on components consisting of carbon, hydrogen, and oxygen only
    • C10L1/026—Liquid carbonaceous fuels essentially based on components consisting of carbon, hydrogen, and oxygen only for compression ignition
    • C—CHEMISTRY; METALLURGY
    • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
    • C11C—FATTY ACIDS FROM FATS, OILS OR WAXES; CANDLES; FATS, OILS OR FATTY ACIDS BY CHEMICAL MODIFICATION OF FATS, OILS, OR FATTY ACIDS OBTAINED THEREFROM
    • C11C3/00—Fats, oils, or fatty acids by chemical modification of fats, oils, or fatty acids obtained therefrom
    • C11C3/003—Fats, oils, or fatty acids by chemical modification of fats, oils, or fatty acids obtained therefrom by esterification of fatty acids with alcohols
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10G—CRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
    • C10G2300/00—Aspects relating to hydrocarbon processing covered by groups C10G1/00 - C10G99/00
    • C10G2300/10—Feedstock materials
    • C10G2300/1011—Biomass
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E50/00—Technologies for the production of fuel of non-fossil origin
    • Y02E50/10—Biofuels, e.g. bio-diesel
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P30/00—Technologies relating to oil refining and petrochemical industry
    • Y02P30/20—Technologies relating to oil refining and petrochemical industry using bio-feedstock

Definitions

  • the invention relates to a process for the purification of biodiesel.
  • biodiesel Due to its origin from renewable raw materials, biodiesel has a neutral carbon dioxide balance during combustion. Carbon dioxide is one of the greenhouse gases whose emissions are being pushed back to counteract the global warming of the climate. Biodiesel is said to play an important role as a substitute for diesel derived from fossil sources. This is also supported by state measures. Within the European Union, for example, a share of biodiesel in diesel fuels is required by law.
  • Biodiesel is made by the alcoholysis of triglycerides, one mole of triglyceride reacting with three moles of alcohol to one mole of glycerol and three moles of the corresponding fatty acid ester.
  • the reaction involves three reversible reactions whereby the triglyceride is gradually transformed into a diglyceride, a monoglyceride and finally into glycerol.
  • one mole of alcohol is consumed and one mole of a fatty acid ester is released.
  • methanol is used as alcohol.
  • biodiesel is also commercially available which contains ethyl or propyl fatty acid esters.
  • the alcohol is used to ⁇ particular methanol, in most industrial processes in stoichiometric excess.
  • a further advantage of the methanolysis of triglycerides is that the glycerol formed during the reaction does not mix with the fatty acid methyl ester and therefore a phase separation is observed, with an upper ester phase and a lower glycerol phase. The glycerol can therefore be easily separated from the reaction mixture, whereby the balance is further shifted to the side of the fatty acid ester.
  • the transesterification can be carried out as a one-step process. However, it is also possible to carry out the transesterification in several stages.
  • Alcoholysis can be carried out under both acidic and basic catalysis.
  • the alcoholysis In the industrial production of biodiesel, the alcoholysis is usually carried out under alkaline catalysis, since the reaction then proceeds under mild conditions at a high conversion rate and therefore relatively fast.
  • the alkaline catalysts used usually work less corrosive to the synthesis reactors, so that, for example, a relatively inexpensive carbon steel can be used for plant construction.
  • the alcoholysis of the triglycerides is carried out under homogeneous alkaline catalysis.
  • the alkoxide ion acting as a catalyst is produced by, for example, dissolving an alkali metal alcoholate in the alcohol or reacting the pure alkali metal with the alcohol.
  • a corresponding alkali metal hydroxide can be dissolved in the methanol. Since alcoholysis of triglycerides leads to relatively rapid phase separation by the glycerol formed, the predominant portion of the alkaline catalyst is removed relatively rapidly from the reaction mixture. The resulting fatty acid esters are therefore barely in contact with the catalyst, so that the risk of saponification is low. Based on the oil used, the catalyst is usually used in an amount of 0.5 to 1 wt .-%. For details of biodiesel production, see the monograph by M. Mittelbach, C. Remschmidt, "Biodiesel, The Comprehensive Handbook," Graz, 2004; ISBN 3-200-00249-2 is referenced.
  • the triglycerides used as starting materials can be obtained, for example, from plants or animal fat.
  • vegetable raw materials four main raw materials are used in the world production of biodiesel, with rapeseed being the most important source, followed by sunflower oil, soybean oil and palm oil.
  • Other starting materials of commercial importance are animal fats, such as beef tallow, as well as used frying fats.
  • biodiesel may contain up to 0.2% by weight of monoglycerides, up to 0.8% by weight of diglycerides and up to 0.02% by weight of triglycerides - A -
  • biodiesel soaps must also be removed from the biodiesel, otherwise ash can form during combustion, which can be deposited and lead to damage to the diesel engine.
  • a water wash is therefore usually carried out after transesterification. If the raw biodiesel contains large amounts of soaps, a stable emulsion can form, which makes the separation of the fatty acid esters considerably more difficult.
  • a process for the purification of biodiesel in which the biodiesel is reacted with at least one adsorbent.
  • the adsorbent used is preferably magnesium silicate, particularly preferably a synthetic amorphous hydrated magnesium silicate.
  • the magnesium silicate has been treated to have a pH of less than about 9.0. By using such an adsorbent, most of the contaminants can be removed from the biodiesel.
  • US 2005/0188607 describes a process for removing methanol and other crude biodiesel compounds by mixing a silicon-based adsorbent with the crude biodiesel.
  • the adsorbent used is preferably magnesium silicate.
  • the magnesium silicate proposed for the purification of biodiesel is a synthetic product.
  • the preparation of this adsorbent therefore requires relatively expensive starting materials, energy, as well as corresponding devices for the synthesis. Furthermore fall during the synthesis of waste, which must be reprocessed or landfilled.
  • US 5,972,057 describes a process for producing a diesel fuel from edible oil wastes.
  • solid impurities are first removed from the used edible oil. Then the oil is heated to remove moisture and odors.
  • the prepurified edible oil is then treated with an alcoholic solution of an alkaline base and stirred until a heavier and a lighter phase has formed.
  • the lighter phase is separated and added to the separation of impurities with an adsorbent.
  • Suitable adsorbents are activated carbon, activated clays, acid clays, bentonites, diatomaceous earth, silica gel, active alumina and molecular sieve.
  • the purified fatty acid esters are then separated from the adsorbent.
  • This object is achieved by a method having the features of claim 1.
  • Advantageous embodiments of the method are the subject of the dependent claims.
  • a special adsorbent which contains a proportion of allophane and / or imogolite.
  • Allophane for example, occurs in soils that arise from volcanic ash. The allophane content of these soils, however, is relatively low and is usually in the range of 5 to 15 wt .-%. However, deposits are also known in which the mineral occurs at a level of about 40 to 60 wt .-%. In some deposits even higher levels of allophane occur. Allophane and the structurally related imogolite are mostly socialized. These minerals are not conventional clays which generally have a layered structure.
  • Allophane consists of nanospheres with a diameter in the range of preferably 40 to 60 ⁇ .
  • the diameter of these nanospheres can be determined, for example, by transmission electron spectroscopy or atomic force microscopy.
  • These nanospheres are hollow inside, whereby the cavity can not be occupied by nitrogen (N 2 ), for example, while argon can penetrate and occupy the cavity at least from a certain size of the nanospheres.
  • Allophanes are characterized by a very sharp distribution of the micropore diameter compared to layered clay minerals. These micropores can be attributed to defects in the outer wall of nanospheres formed of aluminum octahedra.
  • Allophane preferably has a specific surface, determined by the BET method according to DIN 66131, of preferably 250 to 400 m 2 / g, preferably 300 to 350 m 2 / g.
  • allophane comprises an SiO 2 octahedral layer, which forms the outer layer of the hollow sphere, and a strongly disordered aluminum tetrahedral layer, which forms the inner layer of the hollow sphere.
  • allophane has a very high number of singly coordinated oxygen atoms, that is to say Al-OH groups arranged on the surface, the oxygen being at least partially seated on unlinked aluminum atoms. The number of these reactive surface groups can be determined by potentiometric titration.
  • the concentration of the reactive surface groups is preferably at least 0.25 mmol / g, more preferably at least 0.35 mmol / g, particularly preferably at least 0.45 mmol / g.
  • the concentration of the reactive surface groups, ie hydroxy groups arranged on the surface of the allophane, is preferably less than 150 mmol / g, preferably less than 100 mmol / g.
  • allophane In contrast to smectites, allophane carries hardly any permanent charges, such as are generated in layer minerals by isomorphous substitution of silicon atoms by aluminum atoms and / or aluminum atoms by magnesium atoms in the crystal lattice. This also requires a low cation exchange capacity of allophanes compared to layer minerals.
  • the allophane contained in the adsorbent preferably has a cation exchange capacity of less than 30 meq / 100 g, particularly preferably less than 20 meq / 100 g, in particular less than 10 meq / 100 g.
  • the properties of the allophan become therefore essentially determined by the hydroxy groups arranged on the surface of the nanospheres.
  • allophane can generally only be converted into a stable suspension at great expense.
  • the hydroxy groups arranged on the surface of the nanospheres are preferably almost completely protonated.
  • a suspension of the allophane is therefore particularly stable when the liquid, aqueous phase has been adjusted to a pH below 4.
  • the ratio SiO 2 AAl 2 O 3 of the allophane is preferably between 0.4 and 1.5, preferably between 0.6 and 1.3, particularly preferably 0.8 and 1.0. Allophane has only a low degree of structural order and therefore shows in the X-ray diagram a strong background scattering in the small angle range and two broad bands with maxima at about 3.3 and 2.25 ⁇ . (Crystal Structures of Clay Minerals and their X-Ray Identification, Mineralogical Society Monograph No. 5, Eds. GW Brindley and G. Brown, Mineralogical Society, 41 Queens Gate, London SW7 5 HR, 1980, especially Chapter 6 " Associated Minerals "by G. Brown, Part 18, p. 405).
  • the DTA curves show only an endothermic reaction between 50 and 300 0 C with a maximum at about 150 0 C, which is based on the release of adsorbed water and hydroxy groups.
  • An exothermic reaction between 900 and 1000 0 C is caused by the formation of mullite and / or 0 (-Al 2 O 3 .
  • Imogolite consists of tubes which have an inner diameter in the range of about 10 ⁇ and an outer diameter of about 20 ⁇ . Always several tubes form bundles, which have a diameter of 100 to 300 ⁇ . Within the bundles, the individual tubes are parallel with a distance of 18 to 20 ⁇ between them.
  • the chemical composition of Imogolit varies only within narrow limits and corresponds approximately to the formula (SiO 2) 1, 0 -1,2Al 2 O 3 (H 2 O) 2, 3 - 3, 0 - lit gleich In Imogo- the aluminum ions are always coordinated six times.
  • Imogolit has an X-ray diagram, which has a larger number of bands compared to allophane. The gangs are less wide and their maxima are sharper. In contrast to allophane, marked reflections can be observed at 12 to 20, 7.8 to 8, and 5.5 to 5.6 ⁇ (GW Brindley et al., Loc cit., P 405).
  • DTA differential thermal analysis
  • Imogolit shows in a temperature range of 50 to 300 0 C, a first endothermic reaction and a second endothermic reaction with a maximum at about 400 0 C. The first reaction corresponds to the release of adsorbed water. The maximum at about 400 0 C is due to a removal of hydroxy groups from the structure of the imogolite.
  • An exothermic reaction just below about 1000 0 C is attributed as in the allophanes to the formation of mullite and / or Ot-Al 2 O 3 .
  • the adsorbent is added to the crude biodiesel, so that impurities can be adsorbed.
  • the amount of adsorbent added is preferably greater than 0.1% by weight, more preferably greater than 1% by weight, based on the crude biodiesel (anhydrous). According to one embodiment, the amount of added adsorbent is less than 5 wt .-%, chosen according to another embodiment, less than 3 wt .-%.
  • the mixture of crude biodiesel and adsorbent is preferably stirred during adsorption. For this purpose, conventional devices can be used.
  • the reaction of the crude biodiesel can be carried out at room temperature.
  • the crude biodiesel is heated slightly, wherein it is preferably heated to a temperature of more than 30 0 C, preferably more than 40 0 C, particularly preferably more than 50 0 C. Heating to very high temperatures is not required. sary.
  • the temperature to which the crude biodiesel is heated less than 90 0 C, more preferably less than 80 0 C, particularly preferably less than 70 0 C.
  • the treatment of the crude biodiesel is preferably carried out at ambient pressure. The duration of treatment depends on the chosen amount of adsorbent and the level of contamination of the crude biodiesel.
  • the adsorbent is preferably left in the crude biodiesel for at least 15 minutes, more preferably at least 30 minutes, most preferably at least 45 minutes.
  • the treatment time is not too high.
  • the adsorbent is left in the crude biodiesel for less than 5 hours, more preferably less than 4 hours, most preferably less than 3 hours.
  • These treatment times relate to an application of the adsorbent in the form of a suspension.
  • the adsorbent may also be provided in the form of a column packing or a cartridge in which the adsorbent is contained. In this case, the speed with which the crude biodiesel passes through the column pack or the filter cartridge is selected such that the biodiesel, after exiting the bed formed from the adsorbent, meets the required specifications.
  • the crude biodiesel may for example be a product which is obtained directly after the alcoholysis of the triglycerides and optionally separation of the glycerol phase.
  • a biodiesel is referred to, which has already undergone a pre-cleaning, such as a water wash.
  • the specification to be fulfilled depends on the use to which the purified biodiesel is to be supplied.
  • the raw biodiesel and the pure biodiesel obtained by the process according to the invention are characterized in that the pure biodiesel contains at least one impurity in a lesser amount than the crude biodiesel.
  • Exemplary impurities are mono-, di- and triglycerides, soaps, methanol, water, or residues of catalysts for the alcoholysis of triglycerides remaining in the biodiesel.
  • a crude biodiesel is understood in particular to mean a biodiesel which contains more than 0.02% by weight of glycerol and / or more than 600 ppmw of soaps and / or more than 1000 ppmw of water and / or more than 0.2% by weight of diglycerides and / or contains more than 0.8% by weight of monoglycerides and / or more than 0.02% by weight of triglycerides.
  • a crude biodiesel is also understood as meaning, for example, a biodiesel which has a total glycerol content of more than 0.23% by weight.
  • Total glycerol content refers to the sum of free glycerol and glycerol bound in mono-, di- and triglycerides.
  • the total glycerol content can be determined using standardized methods.
  • European Standard EN 14 105 is cited, in which the total glycerol content is determined by means of gas chromatographic methods.
  • a pure biodiesel is correspondingly preferably understood to mean a biodiesel which meets the specifications, preferably for use as fuel in diesel engines, in particular for passenger cars.
  • the pure biodiesel contains less than 0.02 wt .-%, more preferably less than 0.01 wt .-% glycerol and / or less than 600 ppmw, more preferably less than 100 ppmw, particularly preferably less than 50 ppmw soaps and / or less than 1000 ppmw, particularly preferably less than 500 ppmw of water and / or less than 0.8% by weight, particularly preferably less than 0.3% by weight of monoglycerides and / or less than 0.2% by weight.
  • the total glycerol content of the pure biodiesel is less than 0.23 wt .-%, particularly preferably less than 0.2 wt .-%, particularly preferably less than 0.1 wt .-%.
  • the separation of the adsorbent from the purified biodiesel is carried out by conventional methods.
  • the adsorbent may be allowed to settle, after which the purified biodiesel is decanted off.
  • the adsorbent is separated by filtration, wherein the filtration can be carried out under pressure.
  • the filtration can take place via a suitable filter, which reliably retains the particles of the adsorbent.
  • the filtration can also be carried out in the form of a precoat filtration. In this case, a layer of an inert filter medium is first applied to a suitable filter, for example a fine mesh, which is retained by the filter.
  • a suitable filter medium is kieselguhr, for example.
  • the suspension of the adsorbent in the pure biodiesel is passed through the layer of the inert filter medium, wherein the adsorbent is retained by the layer of the inert filter medium and forms with this a filter cake for the filtration of the subsequent biodiesel.
  • the content of the adsorbent on allophane and / or imogolite is preferably chosen to be high in order, for example, to keep the proportion of biodiesel remaining in the filter cake as low as possible.
  • the proportion of the allophane and / or imogolite contained in the adsorbent is preferably more than 20% by weight, particularly preferably more than 60% by weight, in particular more than 80% by weight.
  • the adsorbent may be less as 100 wt .-%, possibly less than 90 wt .-% allophane and / or imogolite.
  • the preparation of the adsorbent can be done in various ways. If a mineral having a very high allophane and / or imogolite content is used as the starting material, preferably a mineral which has a proportion of allophane and / or imogolite of more than 60% by weight, particularly preferably more than 80% by weight, the mineral can be used directly in the erfmdungsgespecializeden method as adsorbent.
  • the mineral is preferably first dried, preferably to a moisture content of about 10 to 30 wt .-%. This can be done by drying in air.
  • the mineral used as the starting material may also be heated, preferably to a temperature in the range of 60 to 120 ° C.
  • This air-dry material is then preferably broken to the desired particle size, which is chosen depending on the intended use.
  • the particle size is preferably selected in the range from 0.1 to 10 mm, particularly preferably 1 to 8 mm, particularly preferably 2 to 5 mm. But it is also possible to break the material only after another production step.
  • the dried material is then preferably calcined at elevated temperature. For the calcination, the temperature is preferably higher than 150 ° C., more preferably higher than 200 ° C., especially preferably higher than 250 ° C. Too high temperatures should be avoided when calcining, as the material then adversely changes and, for example, decreases its Adsorptionskapazitat.
  • the temperature during calcining is preferably chosen to be lower than 400 ° C., particularly preferably lower than 350 ° C.
  • the calcination time depends on the selected calcining temperature and is preferably chosen in the range of 2 to 6 hours.
  • the material may optionally be refracted and sieved to the desired particle size. Such a material can then directly can be used in the process according to the invention.
  • Such an adsorbent preferably has a bulk density of 300 to 700 g / cm 3 , more preferably 400 to 600 g / cm 3 .
  • the pit-moist starting mineral is preferably first broken into smaller pieces and then preferably mixed with water and extruded to unlock larger aggregates. Subsequently, the material is dispersed with a stirrer or by means of ultrasound. With the help of, for example, a hydrocyclone larger particles, preferably with a particle size of> 10 microns, separated and preferably recycled back to the dispersion in order to be further digested.
  • the resulting suspension is allowed to sediment and the aqueous phase is decanted off to give an allophane or imido-rich sludge which has a solids content of preferably more than 10% by weight, preferably 15 to 30% by weight.
  • This sludge is further dewatered, for example by means of a filter press or a multi-chamber separator.
  • the filter cake obtained is preferably dried. The drying is preferably carried out at elevated temperature, preferably at a temperature in the range from 50 to 100 ° C. Subsequently, the material is preferably still calcined, it being possible to use the abovementioned conditions.
  • the particle size of the adsorbent is adjusted so that the adsorbent can be separated from the purified biodiesel without difficulty by conventional methods.
  • the dry residue of the adsorbent on a sieve of mesh size 63 ⁇ m is preferably set in the range from 20 to 40% by weight and the dry sieve residue of the adsorbent on a sieve of mesh size 25 ⁇ m is preferably used in the process.
  • the adsorbent is preferably used in the form of a granulate, the granules having an average particle size of preferably from 1 to 5 mm.
  • the adsorbent is characterized by a comparatively high specific surface, which is preferably at least 200 m 2 / g, preferably at least 250 m 2 / g, particularly preferably at least 300 m 2 / g.
  • the specific surface area of the adsorbent is less than 400 m 2 / g according to one embodiment of the invention.
  • the process itself can be carried out with any type of crude biodiesel.
  • the crude biodiesel is treated with the adsorbent immediately after the alcoholysis of the triglycerides without a further washing step.
  • the adsorbent preferably only the glycerol phase is separated from the crude biodiesel.
  • the adsorbent used in the process according to the invention is characterized by a high adsorption capacity, so that soaps and glycerol, which are still present in the crude biodiesel, can be removed without a pre-cleaning.
  • the biodiesel first in the usual way a water wash.
  • the water wash can be done in one or more stages.
  • water is added to the crude biodiesel, the amount of water relative to the biodiesel being selected to be in the range of preferably 2 to 10% by weight, preferably 4 to 8% by weight.
  • the mixture is easily agitated, with the intensity of the movement chosen so that no stable emulsion is formed.
  • the temperature of the water phase is preferably selected in the range of 20 to 90 0 C, particularly preferably 40 to 80 0 C.
  • the duration of treatment of the biodiesel with water depends on the quantities chosen. Preferably, the duration is richly chosen from 10 to 45 minutes.
  • the water washing step is preferably repeated at least once after separation of the water phase, wherein the amount of water and the water temperature can also be selected differently for the first water washing step.
  • the oil is preferably dried.
  • the biodiesel can be heated, for example, preferably to a temperature of more than 90 ° C.
  • biodiesel purified by the water scrubbing does not yet meet the required specification, a post-treatment can be carried out with the method according to the invention, after which the pure biodiesel then fulfills the required specification.
  • the crude biodiesel used in the process according to the invention is preferably obtained by alcoholysis of triglycerides.
  • the triglycerides can be obtained per se from any suitable source of oils and fats.
  • the alcoholysis is carried out according to known methods, acidic or, preferably, alkaline catalysts can be used.
  • the alcohol used is preferably methanol. However, it is also possible to use other alcohols, for example ethanol or propanol. Ethanol offers the opportunity to extract the biodiesel completely from biological sources, since ethanol can be obtained by fermenting organic matter.
  • Fig. 1 shows an X-ray diffractogram of a purified allophane sample (allophane 1) to which corundum has been added as an internal standard
  • Fig. 2 a plot of the proton affinity distribution (Fig. 2b) and the proton equilibrium function, each determined for allophane 1 (0.01 M NaCl).
  • the surface area and the pore volume were determined with a fully automatic nitrogen porosimeter from the company Micromeritics, type ASAP 2010.
  • the sample is cooled in a high vacuum to the temperature of liquid nitrogen. Subsequently, nitrogen is continuously metered into the sample chamber. By detecting the adsorbed amount of gas as a function of pressure, an adsorption isotherm is determined at a constant temperature. After pressure equalization, the analysis gas is gradually removed and a desorption isotherm is recorded.
  • the pore volume is also determined from the measurement data using the BJH method (EP Barret, LG Joiner, PP Haienda, J. Am. Chem Soc 73 (1951, 373)), which also takes into account effects of capillary condensation
  • Pore volumes of certain pore size ranges are determined by summing up incremental pore volumes obtained from the BJH adsorption isotherm evaluation.
  • Total pore volume according to the BJH method refers to pores with a diameter of 1.7 to 300 nm.
  • the X-ray diffraction patterns were recorded with a Philips X ' Pert PW3710 ⁇ -2 ⁇ diffractometer with Cu-K ⁇ radiation (40 kV and 40 mA). A 1 ° divergence diaphragm, a secondary monochromator and a point detector were used. The recorded area covers 2 - 80 ° 2 ⁇ , recorded with a step size of 0.02 ° 2 ⁇ (3 sec per step). The preparations were produced by top-loading technique. Secondary minerals were assigned by software integrated into the instrument by comparison with peak positions and peak intensities cataloged in the ICPDS database (ICPDS: Joint Committee on Powder Diffraction Standards).
  • the sample to be examined is weighed and added with a known amount of an internal standard.
  • the amount of the standard is chosen so that its proportion based on the sample is about 10 to 20 wt .-%.
  • the standard is chosen so that it is not already present as a minor phase in the mineral and reflections of the standard do not overlap with reflections of the mineral.
  • Suitable standards are for example zinc oxide or corundum.
  • the standards should be high quality. Suitable standards include "NIST" standards (http: // www, nist .gov).
  • the X-ray diffraction diagram is evaluated by Rietveld analysis.
  • the internal standard is overdetermined to the extent that the allophane and other X-ray amorphous constituents are present in the sample. X-ray diffraction and Rietveld analysis can be used to determine the proportion of the various minerals in the sample. By addition of the individual minerals contained in the sample, a theoretical elemental composition can again be determined.
  • a second sample of the mineral is purified to the extent that only the pure allophane is present. Subsequently, the Al / Si ratio of the allophane is determined by elemental analysis.
  • the elemental composition of the mineral is chemically determined by total elimination.
  • the water content of the products at 105 0 C is determined using the method DIN / ISO-787/2.
  • This analysis is based on the total amount of raw clay or the corresponding product. After dissolving the solids The individual components are analyzed and quantified using conventional specific analysis methods, such as ICB.
  • the sample digestion finely ground about 10 g of the sample to be examined and dried in a drying oven at 105 ° C. for 2 to 3 hours to constant weight. Approximately 1.4 g of the dried sample are placed in a platinum crucible and the sample weight is determined to an accuracy of 0.001 g. Thereafter, the sample is mixed in the platinum crucible with 4 to 6 times the weight of a mixture of sodium carbonate and potassium carbonate (1: 1). The mixture is provided with the platinum crucible into a Simon-Müller furnace and 2 - 3 hours at 800 - 850 0 C melted. The platinum crucible with the melt is removed from the oven with a platinum plunger and left to cool.
  • the cooled melt is rinsed with a little distilled water in a casserole and carefully mixed with concentrated hydrochloric acid. After completion of the evolution of gas, the solution is evaporated to dryness. The residue is again concentrated in 20 ml. Hydrochloric acid and evaporated again to dryness. The evaporation with hydrochloric acid is repeated again.
  • the residue is moistened with about 5 - 10 ml of hydrochloric acid (12%), with about 100 ml of dist. Water is added and heated. Insoluble SiO 2 is filtered off, the residue washed three times with hot hydrochloric acid (12%) and then washed with hot water (dist.) Until the filtrate water is chloride-free.
  • the SiO 2 is ashed with the filter and weighed.
  • the filtrate collected in the silicate determination is transferred to a 500 ml volumetric flask and supplemented with distilled water up to the calibration mark. From this solution are then using FAAS aluminum, iron, calcium and magnesium determination performed.
  • the method allows the determination of the hydroxy groups arranged on the surface of the allophane which have a pKa of between 2.5 and 11.5.
  • the titration data were converted into the proton equilibrium function according to Ward & Brady (Ward, DB, Brady, PV (1998): Effect of Al and Organic Acids on the Surface Chemistry of Kaolinite - Clays and Clay Minerals, 46, p , This practically represents the proton desorption isotherm. If the corresponding curve is differentiated, an image of the proton affinity distribution is obtained. From the proton balance function it is possible to read directly the content of a surface group (in the respective pKs limits). The determined proton equilibrium function is shown in FIG. 2b, the associated proton affinity distribution in FIG. 2a. If a tangent is plotted in the curve of the proton affinity distribution, the pK value can be determined, which corresponds to the decrease of the curve to the zero line. With the pK value thus determined, the concentration of the reactive can be determined from the proton equilibrium function Determine groups or arranged on the surface of the allophane 1 hydroxy groups.
  • the acidity index expressed in mg KOH / g oil, was determined according to the instructions of the American Oil Chemical Society No. Cd 3d-63.
  • Free glycerine and total glycerol were determined by the iodometric titration of periodic acid according to the protocol of the American Oil Chemical Society No. Ca 14-56.
  • the content of soaps was determined according to the American OiI Chemistry Society Cc 17-79.
  • the samples allophane 3 and 4 were obtained without separation of mecanicinerals.
  • the pit-wet mineral was first dried in air and then at 60 0 C, ground and separated the grain class of 1 to 5 mm by sieving. The separated material was then calcined for 2 hours at 300 ° C.
  • the adsorbents used in the examples have the following characteristic properties: Table 1: Characterization of different allophanes
  • Table 2 Silicate analyzes In the case of allophane 1, the proportion of reactive hydroxyl groups arranged on the surface of the allophane was also determined. A proportion of 0.5 mmol / g was determined. The proton equilibrium function is shown in Fig. 2b and the proton affinity distribution is shown in Fig. 2a.
  • a biodiesel made from crude soybean oil was used, i. the soybean oil had neither been bleached nor deodorized before alcoholysis.
  • the parameters determined for the biodiesel produced from the raw soybean oil are summarized in Table 3. For comparison, the values obtained for a crude biodiesel prepared from a bleached and deodorized soybean oil are shown.
  • Magnesol ® The Dallas Group of America, Inc., USA, which is described in WO 2005/037962 A2 a special magnesium silicate.
  • All three adsorbents reduce the content of biodiesel samples relative to total glycerol and free glycerol over crude biodiesel.
  • allophane 1 shows the best cleaning effect among the three investigated materials.
  • the data also show that treatment with allophane 1 can produce pure biodiesel of a quality which is the glycerol content is the usual standard Fulfills.
  • Raw biodiesel can therefore be cleaned in one step, ie without carrying out a customary wet scrubbing process, to the extent that the standard is met.
  • Example 3 Aesorbent treatment of biodiesel made from bleached palm oil
  • a biodiesel made from bleached palm oil was used.
  • the raw biodiesel had the following characteristic parameters:
  • the raw biodiesel By washing with water, the raw biodiesel can already be cleaned to meet standards in terms of the amount of free glycerin and the acidity index. However, the content of total glycerol is not met.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Wood Science & Technology (AREA)
  • Fats And Perfumes (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

Abstract

L'invention concerne un procédé de purification de biodiesel, selon lequel un biodiesel brut est mélangé avec un adsorbant qui contient de l'allophane et/ou de l'imogolite. Selon l'invention, un biodiesel pur qui présente un degré d'impuretés réduit par rapport au biodiesel brut est obtenu après la séparation de l'adsorbant.
PCT/EP2008/010481 2007-12-12 2008-12-10 Purification de biodiesel par de l'allophane et/ou de l'imogolite WO2009074307A2 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102007059620.2 2007-12-12
DE102007059620A DE102007059620A1 (de) 2007-12-12 2007-12-12 Aufreinigung von Biodiesel mittels Allophan und/oder Imogolit

Publications (2)

Publication Number Publication Date
WO2009074307A2 true WO2009074307A2 (fr) 2009-06-18
WO2009074307A3 WO2009074307A3 (fr) 2010-03-11

Family

ID=40679829

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP2008/010481 WO2009074307A2 (fr) 2007-12-12 2008-12-10 Purification de biodiesel par de l'allophane et/ou de l'imogolite

Country Status (2)

Country Link
DE (1) DE102007059620A1 (fr)
WO (1) WO2009074307A2 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2016098025A1 (fr) 2014-12-17 2016-06-23 Inis Biotech Llc Procédé de purification de biodiesel

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BRPI1005000A2 (pt) * 2010-11-26 2013-03-26 Mineracao Curimbaba Ltda processo para obtenÇço de biodiesel a partir de àleos e/ou gorduras vegetais e/ou gorduras animais, virgens ou usados e biodiesel assim obtido

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5611853A (en) * 1994-09-06 1997-03-18 Haruo Morimoto Composition of matter and solid medium based-on naturally-occurring humic allophane soil useful in treatment of fluids
US5972057A (en) * 1997-11-11 1999-10-26 Lonford Development Limited Method and apparatus for producing diesel fuel oil from waste edible oil
WO2007076163A2 (fr) * 2005-12-29 2007-07-05 Archer-Daniels-Midland Company Procedes de production de biodiesel et biodiesel ainsi produit
EP1829853A2 (fr) * 2006-02-02 2007-09-05 Renewable Energy Group, Inc. Procédé de filtrage à froid du biodiesel

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4301686C1 (de) * 1993-01-22 1994-03-31 Chem & Pharm Patent Hold Ltd Verfahren zur Herstellung von Fettsäureestern niederer Alkohole
CN100457871C (zh) 2003-10-09 2009-02-04 美国达拉斯集团公司 采用吸附剂材料的生物柴油的精制
JPWO2005037962A1 (ja) 2003-10-16 2006-12-28 日本ガス合成株式会社 プロパンまたはブタンを主成分とする液化石油ガスの製造方法
US20050188607A1 (en) 2004-01-31 2005-09-01 Lastella Joseph P. System for removal of methanol from crude biodiesel fuel

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5611853A (en) * 1994-09-06 1997-03-18 Haruo Morimoto Composition of matter and solid medium based-on naturally-occurring humic allophane soil useful in treatment of fluids
US5972057A (en) * 1997-11-11 1999-10-26 Lonford Development Limited Method and apparatus for producing diesel fuel oil from waste edible oil
WO2007076163A2 (fr) * 2005-12-29 2007-07-05 Archer-Daniels-Midland Company Procedes de production de biodiesel et biodiesel ainsi produit
EP1829853A2 (fr) * 2006-02-02 2007-09-05 Renewable Energy Group, Inc. Procédé de filtrage à froid du biodiesel

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2016098025A1 (fr) 2014-12-17 2016-06-23 Inis Biotech Llc Procédé de purification de biodiesel

Also Published As

Publication number Publication date
WO2009074307A3 (fr) 2010-03-11
DE102007059620A1 (de) 2009-06-18

Similar Documents

Publication Publication Date Title
KR100675111B1 (ko) 활성 백토 정형 입자, 그 제조 방법 및 그 용도
WO2009077161A2 (fr) Procédé de production d'alkylesters d'acides gras
US20100132251A1 (en) Method for purification of biodiesel
EP1893329A1 (fr) Argiles a surface riche servant a produire des terres decolorantes, et procede d'activation de ces argiles
EP2200960A2 (fr) Procédé de production de propane-1,2-diol par hydrogénation à basse pression de glycérine
JP2010508147A (ja) アモルファス吸着剤、それを得るための方法、及び油脂及び／又は油の漂白におけるその使用
EP2285940B1 (fr) Procédé d'élimination de stérylglycosides de biodiesel
US20110166011A1 (en) Novel active clay and decolorizing agent for animal and plant fats and oils or for mineral oils
US9238785B2 (en) Method for biodiesel and biodiesel precursor production
EP2627744A1 (fr) Procédé d'élimination de composés contenant du phosphore de compositions contenant des triglycérides
WO2009074307A2 (fr) Purification de biodiesel par de l'allophane et/ou de l'imogolite
WO2007079981A2 (fr) Procédé naturel de blanchiment d'huiles
US5264597A (en) Process for refining glyceride oil using precipitated silica
CA1333617C (fr) Procede de raffinage des huiles a base de glycerides
EP2361150A1 (fr) Adsorbants renfermant de l'oxyde d'aluminium pour la purification de biodiesel
WO2004105936A1 (fr) Terre decolorante semi-synthetique
RU2510292C1 (ru) Способ получения сорбента цезия
EP0938375A1 (fr) Acide polysilicique (silice) synthetique contenant du fer et de l'aluminium pour le traitement des huiles
EP2655560A1 (fr) Procédé d'épuration de liquides organiques avec de l'acide méthanesulfonique
CN et al. kk kkkLLLL kkkkkS LkkkS g FR, GB, GR. ITU, IE, IS, IT, IT, LU, IN, MC, MT, NL, PL
EP2483380A1 (fr) Utilisation d'adsorbants à base d'aluminosilicates pour la purification de triglycérides
WO2010015331A2 (fr) Composition catalytique de transestérification
WO2008151824A1 (fr) Immobilisation d'enzymes sur des terres décolorantes
DE102008021665A1 (de) Verfahren zur Umesterung von Triglyceriden
DE102008064135A1 (de) Verfahren zur basenkatalysierten Herstellung einer chemischen Verbindung

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 08860489

Country of ref document: EP

Kind code of ref document: A2

122 Ep: pct application non-entry in european phase

Ref document number: 08860489

Country of ref document: EP

Kind code of ref document: A2