| 1. |
|
|
| 2. |
- Christia, Abdi, 1991, et al.
(författare)
-
Ethanol production from alkali-pretreated oil palm empty fruit bunch by simultaneous saccharification and fermentation with mucor indicus
- 2016
-
Ingår i: International Journal of Green Energy. - : Informa UK Limited. - 1543-5075 .- 1543-5083. ; 13:6, s. 566-572
-
Tidskriftsartikel (refereegranskat)abstract
- Oil palm empty fruit bunch (OPEFB) is a potential raw material for production of lignocellulosic bioethanol. The OPEFB was pretreated with 8% sodium hydroxide (NaOH) solution at 100°C for 10 to 90 min. Enzymatic digestion was carried out using cellulase and β-glucosidase at 45°C for 24 h. It was then inoculated with Mucor indicus spores suspension and fermented under anaerobic conditions at 37°C for 96 h. Sodium hydroxide pretreatment effectively removed 51–57% of lignin in the OPEFB and also its hemicellulose (40–84%). The highest glucan digestibility (0.75 g/g theoretical glucose) was achieved in 40-min NaOH pretreatment. Fermentation by M. indicus resulted in 68.4% of the theoretical ethanol yield, while glycerol (16.2–83.2 mg/g), succinic acid (0–0.4 mg/g), and acetic acid (0–0.9 mg/g) were its by-products. According to these results, 11.75 million tons of dry OPEFB in Indonesia can be converted into 1.5 billion liters of ethanol per year.
|
|
| 3. |
- Jeihanipour, Azam, 1982, et al.
(författare)
-
Enhancement of ethanol and biogas production from high-crystalline cellulose by different modes of NMMO pretreatment
- 2010
-
Ingår i: Biotechnology and Bioengineering. - : Wiley. - 0006-3592 .- 1097-0290. ; 105:3, s. 469-476
-
Tidskriftsartikel (refereegranskat)abstract
- Pretreatment of high-crystalline cellulose with N-methyl-morpholine-N-oxide (NMO or NMMO) to improve bioethanol and biogas production was investigated. The pretreatments were performed at 90 and 120°C for 0.5–15 h in three different modes, including dissolution (85% NMO), ballooning (79% NMO), and swelling (73% NMO). The pretreated materials were then enzymatically hydrolyzed and fermented to ethanol or anaerobically digested to biogas (methane). The pretreatment at 85% NMO, 120°C and 2.5 h resulted in 100% yield in the subsequent enzymatic hydrolysis and around 150% improvement in the yield of ethanol compared to the untreated and water-treated material. However, the best results of biogas production were obtained when the cellulose was treated with swelling and ballooning mode, which gave almost complete digestion in 15 days. Thus, the pretreatment resulted in 460 g ethanol or 415 L methane from each kg of cellulose. Analysis of the structure of treated and untreated celluloses showed that the dissolution mode can efficiently convert the crystalline cellulose I to cellulose II. However, it decreases the water swelling capacity of the cellulose. On the other hand, swelling and ballooning modes in NMO treatment were less efficient in both water swelling capacity and cellulose crystallinity. No cellulose loss, ambient pressure, relatively moderate conditions, and high efficiency make the NMO a good alternative for pretreatment of high-crystalline cellulosic materials.
|
|
| 4. |
- Lennartsson, Patrik R, 1983, et al.
(författare)
-
Effects of different growth forms of Mucor indicus on cultivation on dilute-acid lignocellulosic hydrolyzate, inhibitor tolerance, and cell wall composition
- 2009
-
Ingår i: Journal of Biotechnology. - : Elsevier BV. - 0168-1656 .- 1873-4863. ; 143:4, s. 255-261
-
Tidskriftsartikel (refereegranskat)abstract
- The dimorphic fungus Mucor indicus was grown in different forms classified as purely filamentous, mostly filamentous, mostly yeast-like and purely yeast-like, and the relationship between morphology and metabolite production, inhibitor tolerance and the cell wall composition was investigated. Low concentrations of spores in the inoculum with subsequent aeration promoted filamentous growth, whereas higher spore concentrations and anaerobic conditions promoted yeast-like growth. Ethanol was the main metabolite with glycerol next under all conditions tested. The yields of ethanol from glucose were between 0.39 and 0.42 g g(-1) with productivities of 3.2-5.0 g l(-1) h(-1). The ethanol productivity of mostly filamentous cells was increased from 3.9 to 5.0 g l(-1) h(-1) by the presence of oxygen, whereas aeration of purely yeast-like cells showed no such effect. All growth forms were able to tolerate 4.6 g l(-1) furfural and 10 g l(-1) acetic acid and assimilate the sugars, although with different consumption rates. The cell wall content of the fungus measured as alkali insoluble materials (AIM) of the purely yeast-like cells was 26% of the biomass, compared to 8% of the pure filaments. However, the chitosan concentration of the filaments was 29% of the AIM, compared to 6% of the yeast-like cells.
|
|
| 5. |
- Lennartsson, Patrik R, 1983, et al.
(författare)
-
Ethanol production from lignocellulose by the dimorphic fungus Mucor indicus
- 2008
-
Ingår i: World Bioenergy. Jönköping, Sweden, 27-29 May, 2008.
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Ethanol production from dilute-acid hydrolyzate by the dimorphic fungus Mucor indicus was investigated. A mixture of different forest wood chips dominated by spruce was hydrolyzed with 0.5 g/L sulfuric acid at 15 bar for 10 min, yielding different sugars including galactose, glucose, mannose, and xylose, but also different fermentation inhibitors such as acetic acid, furfural, hydroxymethyl furfural (HMF), and phenolic compounds. We induced different morphological growth of M. indicus from purely filamentous, mostly filamentous, mostly yeast-like to purely yeast-like. The different forms were then ysed to ferment the hydrolyzate. They tolerated the presence of the inhibitors under anaerobic batch cultivation well and the ethanol yield was 430-440 g/kg consumed sugars. The ethanol productivity depended on the morphology. Judging from these results, we conclude that M. indicus is useful for ethanol production from toxic substrates independent of its morphology.
|
|
| 6. |
- Mirahmadi, K., et al.
(författare)
-
Alkaline Pretreatment of Spruce and Birch to Improve Bioethanol and Biogas Production
- 2010
-
Ingår i: BioResources. - : Wiley. - 1930-2126 .- 1930-2126. ; 5:2, s. 928-938
-
Tidskriftsartikel (refereegranskat)abstract
- Alkaline pretreatment with NaOH under mild operating conditions was used to improve ethanol and biogas production from softwood spruce and hardwood birch. The pretreatments were carried out at different temperatures between minus 15 and 100 degrees C with 7.0% w/w NaOH solution for 2 h. The pretreated materials were then enzymatically hydrolyzed and subsequently fermented to ethanol or anaerobically digested to biogas. In general, the pretreatment was more successful for both ethanol and biogas production from the hardwood birch than the softwood spruce. The pretreatment resulted in significant reduction of hemicellulose and the crystallinity of cellulose, which might be responsible for improved enzymatic hydrolyses of birch from 6.9% to 82.3% and spruce from 14.1% to 35.7%. These results were obtained with pretreatment at 100 degrees C for birch and 5 degrees C for spruce. Subsequently, the best ethanol yield obtained was 0.08 g/g of the spruce while pretreated at 100 degrees C, and 0.17 g/g of the birch treated at 100 degrees C. On the other hand, digestion of untreated birch and spruce resulted in methane yields of 250 and 30 l/kg VS of the wood species, respectively. The pretreatment of the wood species at the best conditions for enzymatic hydrolysis resulted in 83% and 74% improvement in methane production from birch and spruce.
|
|
| 7. |
- Mohamadi, Marzieh, 1988, et al.
(författare)
-
A morpholinium ionic liquid for rice straw pretreatment to enhance ethanol production
- 2019
-
Ingår i: Industrial Crops and Products. - : Elsevier BV. - 0926-6690 .- 1872-633X. ; 139
-
Tidskriftsartikel (refereegranskat)abstract
- Rice straw was successfully pretreated with a novel and inexpensive morpholinium ionic liquid, 1-H-3-methylmorpholinium chloride ([HMMorph][Cl]). The influence of water (30, 40, 50% w/w) and dimethyl sulfoxide (DMSO) (10, 30% w/w), as co-solvents, pretreatment time (2, 3, 5 h), temperature (90, 105, 120 °C), solid loading (5, 6.7, 10% w/w), and straw particle size (<0.177, 0.177–0.841 mm, and 0.841–2 mm) were investigated for maximum ethanol production. The best results were obtained in 50% water, at 120 °C and 5% (w/w) solid loading for 5 h from 0.177 – 0.841 mm straw particles. The hydrolysis yield was increased from 33.2% to 70.1%, while ethanol production yield was improved from 21.9% to 64% of the theoretical maximum. The performance of the IL was comparable to 1-ethyl-3-methylimidazolium acetate. Simple synthesis process and dilute solution required for the pretreatment with [HMMorph][Cl] offers cost reductions in the use of ILs in biofuel production.
|
|
| 8. |
- Mohamadi, Marzieh, 1988, et al.
(författare)
-
Improvement of ethanol production from birch and spruce pretreated with 1-H-3-methylmorpholinium chloride
- 2019
-
Ingår i: Electronic Journal of Biotechnology. - : Elsevier BV. - 0717-3458. ; 41, s. 95-99
-
Tidskriftsartikel (refereegranskat)abstract
- Background : Pretreatment is the critically important step for the production of ethanol from lignocelluloses. In this study, hardwood birch (Betula pendula) and softwood spruce (Norway spruce) woods were pretreated with a newly synthesized morpholinium ionic liquid, 1-H-3-methylmorpholinium chloride ([HMMorph][Cl]), followed by enzymatic hydrolysis and fermentation to ethanol. Results : [HMMorph][Cl] was synthesized using inexpensive raw materials, i.e., hydrochloric acid and N-methyl morpholine, following a simple process. The influence of pretreatment time (2, 3, 5, and 8 h) and temperature (120 and 140°C) in terms of hydrolysis efficiency was investigated. Glucose yields from enzymatic hydrolysis were improved from 13.7% to 45.7% and 12.9% to 51.8% after pretreatment of birch and spruce woods, respectively, under optimum pretreatment conditions (i.e., at 140°C for 3 h) as compared to those from pristine woods. Moreover, the yields of ethanol production from birch and spruce were increased to 34.8% and 44.2%, respectively, while the yields were negligible for untreated woods. Conclusions : This study demonstrated the ability of [HMMorph][Cl] as an inexpensive agent to pretreat both softwood and hardwood.
|
|
