Production of PHA using petroleum by-products
By using petroleum byproducts as a carbon source and combining them with bacterial fermentation technology, the problem of increasing the commercial benefits of polyhydroxyalkanoates has been solved, enabling the efficient production of biodegradable polymers, including homopolymers and copolymers, thus meeting the demand for alternative carbon sources.
Patent Information
- Application Number
- CN202480041625.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2023-06-23
- Filing Date
- 2024-06-24
- Publication Date
- 2026-02-13
AI Technical Summary
In the prior art, the commercial benefits of polyhydroxyalkanoates have increased over time, necessitating the search for alternative carbon sources to produce the polymer, especially those with low commercial value or considered hazardous or environmentally unfriendly.
Using petroleum byproducts as a carbon source, polyhydroxyalkanoates are produced by mixing and fermenting them with bacterial biomass. These include specific petroleum-derived carbon sources such as petroleum fractions and polycyclic aromatic compounds. Fermentation conditions such as temperature and pH are optimized, and the polymers are then separated.
Biodegradable polyhydroxyalkanoates with molecular weights ranging from 1,000 to 500,000 Daltons have been successfully produced, including homopolymers, copolymers, and terpolymers. The efficient production of polymers was achieved using petroleum-derived carbon sources.
Smart Images
Figure CN121532519A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present disclosure relates to biodegradable polymers. More particularly, the present disclosure relates to methods of producing biodegradable polymers, polyhydroxyalkanoates, using petroleum-derived carbon sources as feedstocks. BACKGROUND
[0002] Polyhydroxyalkanoates (PHAs) are a class of bio-based polymers of increasing commercial interest that are also biodegradable and / or compostable. Polyhydroxyalkanoates are most commonly produced by biofermentation, in which a carbon source (i.e., a food source) is converted by bacteria or other microorganisms into the desired polyhydroxyalkanoate. The carbon source used for this biofermentation is typically derived from plant oil, hemicellulose, animal oil, sugar, and / or residues from vegetable oil distillation.
[0003] While these carbon sources have been sufficient to date, as the commercial interest in polyhydroxyalkanoates grows over time, it is desirable to provide alternative carbon sources that can be used to produce polyhydroxyalkanoates.
[0004] Accordingly, it is desirable to produce polyhydroxyalkanoates while utilizing new carbon sources that have otherwise relatively low commercial value and / or that are otherwise considered hazardous or environmentally unfriendly. For example, it is desirable to be able to utilize petroleum byproducts that are otherwise undesirable or of low commercial value to produce polyhydroxyalkanoates. SUMMARY
[0005] According to the present disclosure, the above and other needs are met by methods of producing poly(hydroxyalkanoates) by using petroleum byproducts as carbon sources.
[0006] In a first aspect, the present disclosure provides a method of producing poly(hydroxyalkanoates). In one embodiment, the method includes a first step of mixing a biomass comprising bacteria with a petroleum-derived carbon source. The method also includes a step of fermenting the biomass and the carbon source at a temperature of about 25 °C to about 35 °C for a period of at least 24 hours such that the bacteria of the biomass consume at least a portion of the carbon source and synthesize at least one poly(hydroxyalkanoate). The method further includes a step of separating the at least one poly(hydroxyalkanoate) from the biomass.
[0007] According to the present disclosure, the petroleum-derived carbon source consists of (1) a mixture of petroleum distillates, wherein at least 90% by weight of the petroleum distillates have a boiling point above 400 °C as determined by ASTM D7169, or (2) at least 5% by weight of at least one polycyclic aromatic compound. For example, in some cases, the petroleum-derived carbon source can consist of a particular grade of mineral oil, paraffin wax, pyrolysis oil, and mixtures thereof. The petroleum-derived carbon source can also consist of polycyclic aromatic compounds such as naphthalene and / or anthracene.
[0008] In a particular preferred embodiment, the petroleum-derived carbon source consists of a mixture of petroleum fractions, and at least 50% by weight of the petroleum fractions of the carbon source have a boiling point of above 470°C as determined by ASTM D7169.
[0009] In a particular embodiment, the biomass preferably comprises bacteria selected from the group consisting of the genera *Cupriavidus* sp., *Pseudomonas* sp., *Escherichia* sp., and mixtures thereof.
[0010] In some cases, the bacteria and carbon source of the biomass are preferably mixed at a weight ratio of about 50 to about 99 parts carbon source to 1 part bacteria.
[0011] According to a specific embodiment, the biomass and carbon source are preferably fermented at a pH of about 5 to about 9, more preferably about 6 to about 8, and even more preferably about 6.5 to about 7.5.
[0012] In a particular embodiment, at least one poly(hydroxyalkanoate) preferably has a weight-average molecular weight of at least 1,000 Daltons as determined by ASTM 5296-19. More preferably, at least one poly(hydroxyalkanoate) has a weight-average molecular weight of about 1,000 Daltons to about 3,000,000 Daltons as determined by ASTM 5296-19. Even more preferably, at least one poly(hydroxyalkanoate) has a weight-average molecular weight of about 50,000 Daltons to about 500,000 Daltons as determined by ASTM 5296-19.
[0013] According to a particular embodiment, at least one poly(hydroxyalkanoate) preferably comprises a homopolymer. For example, at least one poly(hydroxyalkanoate) may comprise poly-3-hydroxybutyrate.
[0014] In other embodiments, at least one poly(hydroxyalkanoate) preferably comprises a poly(hydroxyalkanoate) copolymer. For example, the poly(hydroxyalkanoate) may comprise poly-3-hydroxybutyrate-co-3-hydroxyhexanoate (“P(3HB-co-3HHx)”).
[0015] According to some embodiments, the poly(hydroxyalkanoate) copolymer preferably comprises at least 87 mol% of monomer repeating units of hydroxybutyrate (e.g., 3-hydroxybutyrate or 4-hydroxybutyrate) and about 2 mol% to about 13 mol% of monomer residues of a second hydroxyalkanoate having 5 to 12 carbon atoms.
[0016] In yet other embodiments, the poly(hydroxyalkanoate) preferably comprises a poly(hydroxyalkanoate) terpolymer. For example, the poly(hydroxyalkanoate) terpolymer can comprise about 75 mole % to about 99.9 mole % monomer repeat units of 3-hydroxybutyrate, about 0.1 mole % to about 25 mole % monomer repeat units of 3-hydroxyhexanoate, and about 0.1 mole % to about 25 mole % monomer repeat units of a third 3-hydroxyalkanoate having 5 to 12 carbon atoms.
[0017] In some cases, the carbon source preferably consists of at least 5 wt % of at least one polycyclic aromatic compound.
[0018] In particular embodiments, the at least one poly(hydroxyalkanoate) synthesized from one polycyclic aromatic compound comprises a polymer backbone having at least one aromatic or polyaromatic moiety incorporated into the polymer backbone. More preferably, the at least one poly(hydroxyalkanoate) comprises a polymer backbone having at least one anthracene moiety incorporated into the polymer backbone. BRIEF DESCRIPTION OF DRAWINGS
[0019] Other advantages of the present application will be readily appreciated, as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:
[0020] Figure 1 is a graph showing the boiling range distribution of mineral oil used in accordance with one embodiment of the present disclosure;
[0021] Figure 2 is a graph showing the boiling range distribution of paraffin wax used in accordance with one embodiment of the present disclosure; and
[0022] Figure 3 is an NMR spectrum of a polyhydroxyalkanoate synthesized in accordance with one embodiment of the present disclosure. DETAILED DESCRIPTION
[0023] The present disclosure provides methods for producing poly(hydroxyalkanoates) using petroleum byproducts as alternative carbon sources. Not all organic materials can be digested by bacteria. Furthermore, even if a carbon source is digestible, not all carbon sources are suitable for producing polyhydroxyalkanoates. However, it has surprisingly been found that, in accordance with the present disclosure, particular petroleum-derived carbon sources can be used as carbon sources for biologically producing poly(hydroxyalkanoates).
[0024] Generally, the method includes a first step of mixing a biomass comprising bacteria with a petroleum-derived carbon source. The biomass and carbon source are then fermented such that the bacteria of the biomass consume at least a portion of the carbon source and synthesize at least one poly(hydroxyalkanoate). The at least one poly(hydroxyalkanoate) is then separated from the biomass.
[0025] Generally, biofermentation of poly(hydroxyalkanoate) polymers is performed using carbon sources that are agricultural or food-based products. For example, vegetable oils, hemicellulose, animal oils, sugars, and / or residues from vegetable oil distillation are commonly used as carbon sources when producing poly(hydroxyalkanoate) polymers.
[0026] However, according to the present disclosure, a petroleum-derived carbon source is used instead of an agricultural or food-based carbon source.
[0027] In particular, the petroleum-derived carbon source generally comprises either (1) a mixture of petroleum distillates, wherein at least 90 wt% of the petroleum distillates have a boiling point above 400°C as determined by ASTM D7169, or (2) at least 5 wt% of at least one polycyclic aromatic compound.
[0028] For example, in some embodiments, the petroleum-derived carbon source can comprise mineral oil of a particular grade, paraffin wax, pyrolysis oil, and mixtures thereof, wherein at least 90 wt% of the distillates of these carbon sources have a boiling point above 400°C as determined by ASTM D7169.
[0029] For particular embodiments, the petroleum-derived carbon source more preferably comprises a mixture of petroleum distillates, wherein at least 50 wt% of the petroleum distillates of the carbon source have a boiling point above 470°C as determined by ASTM D7169.
[0030] The petroleum-derived carbon source can also comprise polycyclic aromatic compounds. For example, the carbon source can comprise naphthalene, anthracene, and / or other larger polycyclic aromatic compounds. The petroleum-derived carbon source may, for example, comprise at least 5 wt% of at least one polycyclic aromatic compound. In some embodiments, the petroleum-derived carbon source can comprise at least 10 wt% of at least one polycyclic aromatic compound, at least 20 wt% of at least one polycyclic aromatic compound, or at least 30 wt% of at least one polycyclic aromatic compound.
[0031] Thus, it has been surprisingly discovered that, according to the present disclosure, polyhydroxyalkanoates can be produced while utilizing carbon sources that are otherwise of relatively low commercial value and / or otherwise considered hazardous or environmentally unfriendly. This contrasts with the conventional use of carbon sources of agricultural origin, such as vegetable oils, hemicellulose, animal oils, sugars, and / or residues from vegetable oil distillation.
[0032] The petroleum-derived carbon source is mixed with a biomass comprising bacteria. Generally, the amount of petroleum-derived carbon source mixed with the biomass can vary depending on the particular carbon source used. Typically, the petroleum-derived carbon source and the bacteria of the biomass are mixed in a weight ratio of about 10 parts of carbon source to 1 part of bacteria. More preferably, the petroleum-derived carbon source and the biomass are mixed in a weight ratio of about 50 parts to about 99 parts of carbon source to 1 part of bacteria, and still more preferably about 90 parts to about 99 parts of carbon source to 1 part of bacteria.
[0033] Generally, the carbon source and the biomass are mixed in a biofermentor or vessel. The biomass and the carbon source are then fermented at a temperature of about 25 °C to about 35 °C for a period of at least 24 hours such that the bacteria of the biomass consume at least a portion of the carbon source and synthesize at least one poly(hydroxyalkanoate).
[0034] More preferably, the biomass and the carbon source are then fermented at a temperature of about 25 °C to about 35 °C and for a period of at least 72 hours.
[0035] Generally, the biomass and the carbon source are fermented at a pH of about 5 to about 9, more preferably about 6 to about 8, and still more preferably about 6.5 to about 7.5.
[0036] The biomass comprises one or more bacterial species capable of synthesizing poly(hydroxyalkanoate) polymers. Suitable bacterial species that can be included in the biomass include, but are not limited to, bacteria selected from the group consisting of Cupriavidus, Pseudomonas, Escherichia, and mixtures thereof.
[0037] During the fermentation process, the bacteria of the biomass consume at least a portion of the carbon source and synthesize at least one poly(hydroxyalkanoate).
[0038] Generally, the at least one poly(hydroxyalkanoate) synthesized has a weight average molecular weight of at least 1000 Daltons as determined by ASTM 5296-19. More preferably, the at least one poly(hydroxyalkanoate) has a weight average molecular weight of about 5000 Daltons to about 3,000,000 Daltons as determined by ASTM 5296-19. Still more preferably, the at least one poly(hydroxyalkanoate) has a weight average molecular weight of about 50,000 Daltons to about 500,000 Daltons as determined by ASTM 5296-19.
[0039] In various embodiments, the at least one poly(hydroxyalkanoate) synthesized by the biomass can be a homopolymer, a copolymer, a terpolymer, or a mixture of the foregoing.
[0040] In particular embodiments, the at least one poly(hydroxyalkanoate) can comprise a homopolymer. For example, the at least one poly(hydroxyalkanoate) can comprise poly-3-hydroxybutyrate.
[0041] In other embodiments, the at least one poly(hydroxyalkanoate) can comprise a poly(hydroxyalkanoate) copolymer. For example, the poly(hydroxyalkanoate) can comprise poly-3-hydroxybutyrate-co-3-hydroxyhexanoate ("P(3HB-co-3HHx)").
[0042] According to some embodiments, the poly(hydroxyalkanoate) copolymer preferably comprises at least 87 mole % of monomeric repeat units of hydroxybutyrate (e.g., 3-hydroxybutyrate or 4-hydroxybutyrate) and about 2 mole % to about 13 mole % of monomeric residues of a second hydroxyalkanoate having 5 to 12 carbon atoms.
[0043] In yet other embodiments, the poly(hydroxyalkanoate) can comprise a poly(hydroxyalkanoate) terpolymer. For example, the poly(hydroxyalkanoate) terpolymer can comprise about 75 mole % to about 99.9 mole % of monomeric repeat units of 3-hydroxybutyrate, about 0.1 mole % to about 25 mole % of monomeric repeat units of 3-hydroxyhexanoate, and about 0.1 mole % to about 25 mole % of monomeric repeat units of a third 3-hydroxyalkanoate having 5 to 12 carbon atoms.
[0044] Further, in some embodiments in which the carbon source comprises at least one polycyclic aromatic compound, it has also been surprisingly discovered that the at least one poly(hydroxyalkanoate) synthesized from the carbon source can comprise a polymer backbone having at least one aromatic or polyaromatic moiety incorporated into the polymer backbone. For example, in some cases, the at least one poly(hydroxyalkanoate) can comprise at least one anthracene moiety incorporated into its polymer backbone.
[0045] Finally, according to the present disclosure, the at least one poly(hydroxyalkanoate) is isolated from the biomass. This isolation can involve one or a series of steps and can include the addition of various enzymatic reagents, such as a lytic agent to disrupt the cell wall of the bacteria, an endonuclease to cleave the polynucleotide strands in the bacteria, and / or a peptidase to degrade proteins within the bacteria. A surfactant or detergent can also be used to facilitate the isolation of the poly(hydroxyalkanoate) from the biomass.
[0046] Examples
[0047] The following non-limiting examples illustrate various other aspects of the present application. Unless otherwise indicated, temperatures are in degrees Celsius and percentages are by weight based on the dry weight of the formulation.
[0048] In this series of experiments, various carbon source materials were tested to determine whether the bacteria could metabolize the carbon source and use it to synthesize poly(hydroxyalkanoate).
[0049] As an initial step, a series of stock solutions were prepared as follows:
[0050] Solution 1 Buffer Production Media 2 (BPM2)
[0051]
[0052] Solution 2 (NH4)2SO4
[0053]
[0054] Solution 3A Refined, Bleached & Deodorized (RBD) Canola Oil
[0055]
[0056] Solution 3B Anthracene
[0057]
[0058] Solution 3C Naphthalene
[0059]
[0060] Solution 3D Mineral Oil plus 3% Gum Arabic Emulsifier
[0061]
[0062] Solution 3E Paraffin Wax plus 3% Gum Arabic Emulsifier
[0063]
[0064] Solution 3F Mineral Oil without Emulsifier
[0065]
[0066] Solution 3G Paraffin Wax without Emulsifier
[0067]
[0068] The samples of mineral oil and paraffin wax used in solutions 3D-3G were also submitted to SGS Petroleum Laboratory to determine the boiling range distribution of the carbon residues in these compounds according to ASTM D7169. The boiling range distribution data for the mineral oil and paraffin wax are shown in Tables 3 and 4, respectively. Figure 1 and Figure 2
[0069] Next, a series of shake flasks containing production media were prepared from the stock solutions described above. The pH of each shake flask was about 6.8. The composition of each shake flask was as follows:
[0070] BPM2 15% Canola Control Flask #1A
[0071]
[0072] BPM2 5% Canola Control Flask #1B
[0073]
[0074] BPM2 5% Anthracene Flask #2A
[0075]
[0076] BPM2 5% Anthracene Flask #2B
[0077]
[0078] BPM2 5% Naphthalene Flask #3A
[0079]
[0080] BPM2 5% Naphthalene Flask #3B
[0081]
[0082] BPM2 15% Mineral Oil plus Gum Arabic Flask #4A
[0083]
[0084] BPM2 15% Mineral Oil plus Gum Arabic Flask #4B
[0085]
[0086] BPM2 15% Paraffin Wax plus Gum Arabic Flask #5A
[0087]
[0088] BPM2 15% Paraffin Wax plus Gum Arabic Flask #5B
[0089]
[0090] BPM2 15% Mineral Oil Flask #6A
[0091]
[0092] BPM2 15% Mineral Oil Flask #6B
[0093]
[0094] BPM2 15% Paraffin Wax Flask #7A
[0095]
[0096] BPM2 15% Paraffin Wax Flask #7B
[0097]
[0098] It was previously determined that bacteria cannot metabolize the methanol solvent or the arabic gum emulsifier to synthesize poly(hydroxyalkanoates). Therefore, the production medium composition in each shake flask contained only a single possible carbon source for poly(hydroxyalkanoate) synthesis.
[0099] Separately, 60 milliliters of yeast, wheat peptone, and fructose (YWF) medium in a six- pitched 250 mL flask was inoculated with 10 mL of Cupriavidus necator H16 culture and incubated at 30°C; 300 rpm for 18 hours to produce a bacterial inoculum.
[0100] Next, about 9 mL of Cupriavidus necator bacterial inoculum was added to the carbon source mixture in each shake flask. The shake flasks were then incubated in a rotary shaker at 30°C at 300 rpm for 72 hours.
[0101] To recover any poly(hydroxyalkanoates) produced during incubation, the culture from each shake flask was each centrifuged at 10,000 X g for 5 minutes in a 50 mL centrifuge tube. The supernatant was decanted, and the pellet was resuspended in 50 mL RO water using vortex. The pellets were treated in a 250 mL six-pitched flask at 37°C and at 58°C using cocktail A and SeBrite (a protease available from Specialty Enzymes), respectively. Cocktail A consists of a mixture of 5.5 mL Tween 20 surfactant, 5.5 mL Tween 80 surfactant, 0.66 grams of lysozyme, and 44 microliters (μL) of nuclease. Hydrogen peroxide was added, and the pellets were washed twice with RO water and ethanol. After drying (benchtop), the recovered material was analyzed to determine (1) the presence or absence of poly(hydroxyalkanoates) using NMR and / or FTIR analysis, and (2) the mole % of hydroxyhexanoate monomer in any poly-3-hydroxybutyrate-co-3-hydroxyhexanoate (“P(3HB-co-3HHx)”) copolymer using NMR analysis.
[0102] The results were as follows:
[0103]
[0104] From the above results, the presence of poly(hydroxyalkanoates) in cultures containing polyaromatics, anthracene, and naphthalene as the sole carbon source was known, demonstrating the use of these polyaromatic compounds in the production of polyhydroxyalkanoates, including poly(3-hydroxybutyrate) co-poly(3-hydroxyhexanoate) copolymers. In addition, the experiment demonstrated the use of long petroleum-based hydrocarbon chains, such as those found in mineral oil and paraffin wax, in the production of polyhydroxyalkanoates, including the comonomer poly(3-hydroxybutyrate) co-poly(3-hydroxyhexanoate).
[0105] Finally, the polyhydroxyalkanoate samples from the anthracene and naphthalene shake flasks were also subjected to NMR analysis to verify the presence of anthracene and / or naphthalene in the polyhydroxyalkanoate molecules. The sample from the anthracene shake flask was found to have incorporated the aromatic anthracene ring into the polyhydroxyalkanoate polymer chain. This is shown in the NMR spectrum shown below, where the peaks at about 7, 8, and 8.5 indicate the presence of anthracene moieties in the polymer backbone of the polyhydroxyalkanoate. There was no indication that naphthalene was similarly incorporated into the polyhydroxyalkanoate polymer chain. Figure 3
[0106] Embodiments
[0107] The present disclosure is further illustrated by the following embodiments:
[0108] Embodiment 1. A method of producing poly(hydroxyalkanoate) comprising the steps of:
[0109] mixing a biomass comprising bacteria with a petroleum-derived carbon source;
[0110] fermenting the biomass and the carbon source at a temperature of about 25 °C to about 35 °C for a period of at least 24 hours, such that the bacteria of the biomass consume at least a portion of the carbon source and synthesize at least one poly(hydroxyalkanoate); and
[0111] separating at least one poly(hydroxyalkanoate) from the biomass,
[0112] wherein the petroleum-derived carbon source comprises: (1) a mixture of petroleum distillate fractions, wherein at least 90 wt% of the petroleum distillate fractions have a boiling point above 400 °C as determined by ASTM D7169, or (2) at least 5 wt% of at least one polycyclic aromatic compound.
[0113] Embodiment 2. The method of embodiment 1, wherein the petroleum-derived carbon source comprises a mixture of petroleum distillate fractions, and at least 50 wt% of the petroleum distillate fractions of the carbon source have a boiling point above 470 °C as determined by ASTM D7169.
[0114] Embodiment 3. The method of embodiment 1 or 2, wherein the biomass comprises bacteria selected from the group consisting of Chrysomonas, Pseudomonas, Escherichia, and mixtures thereof.
[0115] Embodiment 4. The method of any of the preceding embodiments, wherein the bacteria and the carbon source of the biomass are mixed in a weight ratio of about 50 parts to about 99 parts carbon source to 1 part bacteria.
[0116] Embodiment 5. The method of any of the preceding embodiments, wherein the biomass and the carbon source are fermented at a pH of about 6.5 to about 7.5.
[0117] Embodiment 6. The method of any of the preceding embodiments, wherein the at least one poly(hydroxyalkanoate) has a weight average molecular weight of at least 1,000 Daltons, preferably about 1,000 Daltons to about 3,000,000 Daltons, and more preferably about 50,000 Daltons to about 500,000 Daltons, as determined by ASTM 5296-19.
[0118] Embodiment 7. The method of any of the preceding embodiments, wherein the at least one poly(hydroxyalkanoate) comprises a homopolymer.
[0119] Embodiment 8. The method of any of the preceding embodiments, wherein the at least one poly(hydroxyalkanoate) comprises poly-3-hydroxybutyrate.
[0120] Embodiment 9. The method of any of the preceding embodiments, wherein the at least one poly(hydroxyalkanoate) comprises a poly(hydroxyalkanoate) copolymer.
[0121] Embodiment 10. The method of Embodiment 9, wherein the poly(hydroxyalkanoate) copolymer comprises at least 87 mole % of monomeric repeat units of hydroxybutyrate (e.g., 3-hydroxybutyrate or 4-hydroxybutyrate) and about 2 mole % to about 13 mole % of monomeric residues of a second hydroxyalkanoate having 5 to 12 carbon atoms.
[0122] Embodiment 11. The method of any of the preceding embodiments, wherein the poly(hydroxyalkanoate) comprises a poly(hydroxyalkanoate) terpolymer.
[0123] Embodiment 12. The method of Embodiment 11, wherein the poly(hydroxyalkanoate) terpolymer comprises about 75 mole % to about 99.9 mole % of monomeric repeat units of 3-hydroxybutyrate, about 0.1 mole % to about 25 mole % of monomeric repeat units of 3-hydroxyhexanoate, and about 0.1 mole % to about 25 mole % of monomeric repeat units of a third 3-hydroxyalkanoate having 5 to 12 carbon atoms.
[0124] Embodiment 13. The method of any of the preceding embodiments, wherein the carbon source comprises at least one polycyclic aromatic compound.
[0125] Embodiment 14. The method of embodiment 13, wherein the at least one poly(hydroxyalkanoate) comprises a poly(hydroxyalkanoate) having a polymer backbone with at least one aromatic or polyaromatic moiety incorporated into the polymer backbone.
[0126] Embodiment 15. The method of embodiment 13, wherein the at least one poly(hydroxyalkanoate) comprises a poly(hydroxyalkanoate) having a polymer backbone with at least one anthracene moiety incorporated into the polymer backbone.
[0127] The foregoing description of preferred embodiments of the present disclosure has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the present disclosure to the precise form disclosed. Obvious modifications or variations are possible in light of the above teachings. The embodiments were chosen and described in order to provide the best illustration of the principles of the present disclosure and its practical application to thereby enable one of ordinary skill in the art to utilize the present disclosure in various embodiments and with various modifications as are suited to the particular use contemplated.
Claims
1. A method for producing poly(hydroxyalkanoates), comprising the following steps: Biomass containing bacteria is mixed with petroleum-derived carbon sources; The biomass and the carbon source are fermented at a temperature of 25°C to 35°C for at least 24 hours, such that the bacteria of the biomass consume at least a portion of the carbon source and synthesize at least one poly(hydroxyalkanoate). as well as Separating the at least one poly(hydroxyalkanoate) from the biomass The petroleum-derived carbon source comprises: (1) a mixture of petroleum fractions, wherein at least 90% by weight of the petroleum fractions have a boiling point of 400°C or higher as determined by ASTM D7169, or (2) at least 5% by weight of at least one polycyclic aromatic compound.
2. The method of claim 1, wherein the petroleum-derived carbon source comprises a mixture of petroleum fractions, and at least 50% by weight of the petroleum fractions of the carbon source have a boiling point of 470°C or higher as determined by ASTM D7169.
3. The method according to claim 1, wherein the biomass comprises bacteria selected from the group consisting of *Bacillus*, *Pseudomonas*, *Escherichia*, and mixtures thereof.
4. The method according to claim 1, wherein the bacteria and the carbon source of the biomass are mixed at a weight ratio of 50 to 99 parts of the carbon source to 1 part of the bacteria.
5. The method according to claim 1, wherein the biomass and the carbon source are fermented at a pH of 6.5 to 7.
5.
6. The method of claim 1, wherein the at least one poly(hydroxyalkanoate) has a weight-average molecular weight of at least 1,000 Daltons as determined by ASTM 5296-19.
7. The method of claim 1, wherein the at least one poly(hydroxyalkanoate) comprises a homopolymer.
8. The method of claim 1, wherein the at least one poly(hydroxyalkanoate) comprises poly-3-hydroxybutyrate.
9. The method of claim 1, wherein the at least one poly(hydroxyalkanoate) comprises a poly(hydroxyalkanoate) copolymer.
10. The method of claim 9, wherein the poly(hydroxyalkanoate) copolymer comprises at least 87 mol% of a monomer repeating unit of hydroxybutyrate and 2 mol% to 13 mol% of monomer residues of a second hydroxyalkanoate having 5 to 12 carbon atoms.
11. The method of claim 1, wherein the poly(hydroxyalkanoate) comprises a poly(hydroxyalkanoate) terpolymer.
12. The method of claim 11, wherein the poly(hydroxyalkanoate) terpolymer comprises 75 mol% to 99.9 mol% of a repeating monomer unit of 3-hydroxybutyrate, 0.1 mol% to 25 mol% of a repeating monomer unit of 3-hydroxyhexanoate, and 0.1 mol% to 25 mol% of a repeating monomer unit of a third 3-hydroxyalkanoate having 5 to 12 carbon atoms.
13. The method of claim 1, wherein the carbon source comprises at least one polycyclic aromatic compound.
14. The method of claim 13, wherein the at least one poly(hydroxyalkanoate) comprises a poly(hydroxyalkanoate) having a polymer backbone having at least one aromatic or polyaromatic portion incorporated therein.
15. The method of claim 13, wherein the at least one poly(hydroxyalkanoate) comprises a poly(hydroxyalkanoate) having a polymer backbone having at least one anthracene moiety incorporated therein.