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  • 1.
    Kudahettige-Nilsson, Rasika L.
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik.
    Helmerius, Jonas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik.
    Nilsson, Robert T.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik.
    Sjöblom, Magnus
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik.
    Hodge, David
    Department of Chemical Engineering & Materials Science, Michigan State University, USA; Department of Biosystems & Agricultural Engineering, Michigan State University, USA; DOE Great Lakes Bioenergy Research Center, Michigan State University, USA.
    Rova, Ulrika
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik.
    Biobutanol Production by Clostridium acetobutylicum Using Xylose Recovered from Birch Kraft Black Liquor2015Ingår i: Bioresource Technology, ISSN 0960-8524, E-ISSN 1873-2976, Vol. 176, s. 71-79Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Acetone-Butanol-Ethanol (ABE) fermentation was studied using acid-hydrolyzed xylan recovered from hardwood Kraft black liquor by CO2 acidification as the only carbon source. Detoxification of hydrolyzate using activated carbon was conducted to evaluate the impact of inhibitor removal and fermentation. Xylose hydrolysis yields as high as 18.4% were demonstrated at the highest severity hydrolysis condition. Detoxification using active carbon was effective for removal of both phenolics (76-81%) and HMF (38-52%). Batch fermentation of the hydrolyzate and semi-defined P2 media resulted in a total solvent yield of 0.12-0.13 g/g and 0.34 g/g, corresponding to a butanol concentration of 1.8-2.1 g/L and 7.3 g/L respectively. This work is the first study of a process for the production of a biologically-derived biofuel from hemicelluloses solubilized during Kraft pulping and demonstrates the feasibility of utilizing xylan recovered directly from industrial Kraft pulping liquors as a feedstock for biological production of biofuels such as butanol.

  • 2.
    Helmerius, Jonas
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Vinblad von Walter, Jonas
    Luleå tekniska universitet.
    Rova, Ulrika
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Berglund, Kris A.
    Luleå tekniska universitet.
    Hodge, David B.
    Department of Chemical and Engineering and Materials Science, Michigan State University, Michigan, USA.
    Impact of hemicellulose pre-extraction for bioconversion on birch Kraft pulp properties2010Ingår i: Bioresource Technology, ISSN 0960-8524, E-ISSN 1873-2976, Vol. 101, nr 15, s. 5996-6005Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The combination of hemicellulose extraction with chemical pulping processes is one approach to generate a sugar feedstock amenable to biochemical transformation to fuels and chemicals. Extractions of hemicellulose from silver birch (Betula pendula) wood chips using either water or Kraft white liquor (NaOH, Na2S, and Na2CO3) were performed under conditions compatible with Kraft pulping, using times ranging between 20 and 90 min, temperatures of 130-160 °C, and effective alkali (EA) charges of 0-7%. The chips from select extractions were subjected to subsequent Kraft pulping and the refined pulps were made into handsheets. Several metrics for handsheet strength properties were compared with a reference pulp made without an extraction step. This study demonstrated that white liquor can be utilized to extract xylan from birch wood chips prior to Kraft cooking without decreasing the pulp yield and paper strength properties, while simultaneously impregnating cooking alkali into the wood chips. However, for the alkaline conditions tested extractions above pH 10 resulted in low concentrations of xylan. Water extractions resulted in the highest final concentrations of xylan; yielding a liquor without the presence of toxic or inhibitory inorganics and minimal soluble aromatics that we demonstrate can be successfully enzymatically hydrolyzed to monomeric xylose and fermented to succinic acid. However, water extractions were found to negatively impact some pulp properties including decreases in compression strength, bursting strength, tensile strength, and tensile stiffness while exhibiting minimal impact on elongation and slight improvement in tearing strength index.

  • 3.
    Helmerius, Jonas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Integration of a hemicelluloses extraction step into a forest biorefinery for production of green chemicals2010Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Sustainable use of forest and agricultural resources will play an important role for solving urgent global challenges such as the enhanced green house effect and increasing demand for fossil fuels. The development of processes where lignocellulosic biomass can be refined to several different end-products in the same plant, i.e. a biorefinary, will be important in the development towards a more sustainable society where fossil fuels are replaced. To be able to compete with fossil resources, an efficient production of biomass based products is required in order to maximize overall process economics and to minimize negative environmental impact. One solution to increase profitability for forest biomass based plants can be production of value added derivatives produced through fermentation of sugars from hemicelluloses, extracted from lignocellulosic material. The first part of this thesis investigate the impact of hemicellulose pre-extraction on birch Kraft pulp properties. White liquor and water extractions of hemicelluloses from birch wood chips were performed under conditions compatible with Kraft pulping. The chips from select extractions were subject to subsequent Kraft pulping and the refined pulps were made into hand sheets. Several metrics for hand sheet strength properties were compared with a reference pulp made without an extraction step. This work also includes a demonstration of enzymatic hydrolysis and biological conversion of extracted xylan to succinic acid, a metabolite with the potential of a platform chemical. The study demonstrated that white liquor can be utilized to extract xylan from birch wood chips prior to Kraft cooking without decreasing the pulp yield and paper strength properties, while simultaneously impregnating cooking alkali into the wood chips. Alkaline conditions tested above pH 10 significantly degraded xylan and very low concentrations of xylose were obtained using any of the alkaline extractions. Water extractions resulted in the highest final concentration of xylose, 29.1 g/L; yielding fermentable liquor, but were found to negatively impact some pulp properties including decreases in compression strength, bursting strength, tensile strength and tensile stiffness while exhibiting minimal impact on elongation and slight improvement in tearing strength index. Since hot water extractions gave fermentable liquors, the next study was to integrate the production of green chemicals via hot water hemicellulose extraction of birch wood into a small-scale combined heat and power plant, in this case an externally fired gas turbine. The results show that the extracted wood chips would serve very well as a fuel for combustion and gasification processes due to the relatively high heating value. Most important, the extracted wood chips had low ash content and significantly lower concentrations of alkali metals. In addition a fermentable stream with a xylose concentration of 65 g/L was produced.The second part of this thesis was to optimise the production of the dicarboxylic acid, succinic acid, which can be produced via bioconversion as a renewable building block molecule for production of biodegradable solvents and polyesters. In this study the E. coli strain AFP184, which can ferment both five and six carbon sugars with a limited production of other organic acids was used. Earlier work using a high initial sugar concentration resulted in volumetric productivities of almost 3 g/L h, which is above estimated values for economically feasible production, and final succinic acid concentration was around 40 g/L. To further increase succinic acid concentrations, fermentations using NH4OH, NaOH, KOH, K2CO3, and Na2CO3 as neutralising agents were performed and compared. It was shown that substantial improvements could be made by using alkali bases to neutralise the fermentations. The highest concentrations and productivities were achieved when Na2CO3 was used, 77 g/L and 3 g/L h, respectively. A gradual decrease in succinate productivity was observed during the fermentations, which was shown to be due to succinate accumulation in the broth and not as a result of the addition of neutralising agent or the subsequent increase in osmolarity.

    Ladda ner fulltext (pdf)
    FULLTEXT01
  • 4.
    Hodge, David
    et al.
    Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing.
    Helmerius, Jonas
    Vinblad von Walter, Jonas
    Sun Pine Biodiesel AB, Piteå.
    Lindström, Curt
    Smurfit Kappa Kraftliner AB, Piteå.
    Rova, Ulrika
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Impact of hemicellulose pre-extraction for bioconversion on birch kraft pulp properties2009Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    The carbohydrate portion of lignocellulosic feedstocks are ideally suited to conversion via biochemical transformations because of their crucial role in cellular metabolism. The combination of hemicelluloses extraction with pulping processes could be one way to generate a sugar feedstock amenable to biochemical transformation to fuels and chemical intermediates. White liquor, green liquor, and water HC extractions of birch wood were performed under conditions compatible with the Kraft process, at different times, temperatures and alkali charges. The effective alkali charge was in extractions between 0%-7% and temperature between 130°C-160°C for 20-90 minutes. The xylan yields from different HC extractions were measured and the chips from select HC extractions were cooked, and the refined pulps were made into hand sheets. Several metrics for hand sheet quality were compared with a reference pulp made from the same wood chips. It is possible using white liquor to extract xylan from birch wood chips prior Kraft cooking without decreasing the pulp yield and paper strength properties, and at the same time achieve an impregnation of the wood chips. It is not possible in that extraction to attain extracted and hydrolyzed liquor containing a fermentable concentration of xylose, 2.63 g/L in this study. Increased extracted wood material, increased final acetic acid concentration and decreased final xylan concentration together with increased effective alkali charge at the same extraction temperature and time in white liquor extractions performed support that xylan degradation increases. Using white liquor or green liquor under the conditions investigated degrades xylan resulting in significant losses of xylose that could have been used as substrate in fermentation processes.

  • 5.
    Andersson, Christian
    et al.
    Luleå tekniska universitet.
    Helmerius, Jonas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Hodge, David
    Luleå tekniska universitet.
    Berglund, Kris
    Luleå tekniska universitet.
    Rova, Ulrika
    Luleå tekniska universitet.
    Inhibition of succinic acid production in metabolically engineered Escherichia Coli by neutralizing agent, organic acids, and osmolarity2009Ingår i: Biotechnology progress (Print), ISSN 8756-7938, E-ISSN 1520-6033, Vol. 25, nr 1, s. 116-123Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The economical viability of biochemical succinic acid production is a result of many processing parameters including final succinic acid concentration, recovery of succinate, and the volumetric productivity. Maintaining volumetric productivities >2.5 g L-1 h(-1) is important if production of succinic acid from. renewable resources should be competitive. In this work, the effects of organic acids, osmolarity, and neutralizing agent (NH4OH, KOH, NaOH, K2CO3, and Na2CO3) on the fermentative succinic acid production by Escherichia coli AFP184 were investigated. The highest concentration of succinic acid, 77 g L-1. was obtained with Na2O3. In general, irrespective of the base used, succinic acid productivity per viable cell was significantly reduced as the concentration of the produced acid increased. Increased osmolarity resulting from base addition during succinate production only marginally affected the productivity per viable cell. Addition of the osmoprotectant glycine betaine to cultures resulted in an increased aerobic growth rate and anaerobic glucose consumption rate, but decreased succinic acid yield. When using NH4OH productivity completely ceased at a succinic acid concentration of similar to 40 g L-1. Volumetric productivities remained at 2.5 g L-1 h(-1) for tip to 10 h longer when K- or Na-bases where used instead of NH4OH. The decrease in cellular succinic acid productivity observed during the anaerobic phase was found to be due to increased organic acid concentrations rather than medium osmolarity.

  • 6.
    Lundgren, Joakim
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Helmerius, Jonas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Integration of a hemicellulose extraction process into a biomass based heat and power plant2009Ingår i: Proceedings of ECOS 2009: 22nd International Conference on Efficiency, Cost, Optimization Simulation and Environmental Impact of Energy Systems, Foz do Iguaçú: ABCM, Brazilian Society of Mechanical Sciences and Engineering , 2009Konferensbidrag (Refereegranskat)
    Abstract [en]

    The development of processes where lignocellulosic biomass can be refined to several different end-products in the same plant, i.e. a biorefinery, will be important in the development towards a more sustainable society where fossil fuels are replaced. This paper presents the idea to integrate the production of green chemicals via hot water hemicellulose extraction of birch wood (hardwood) into a small-scale combined heat and power plant (CHP), in this case an externally fired gas turbine. A techno-economically successful concept could provide the option to turn a small- to medium scale CHP plant into a small- to medium scale biorefinery. The results show that the extracted wood-chips would serve very well as a fuel for combustion and gasification processes due to the relatively high heating value, low ash content and significantly lower concentrations of alkali metals. Under the assumed economic conditions, electricity can be produced to a cost in the range of €85.6 to €196.2 per MWhel and a fermentable feedstock stream with a xylose concentration of 65 g/L to a cost in between €0.44 to €4.15 per kg xylose depending on plant size and number of annual operational hours.

    Ladda ner fulltext (pdf)
    FULLTEXT01
  • 7. Andersson, Christian
    et al.
    Helmerius, Jonas
    Berglund, Kris
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Rova, Ulrika
    Effects of neutralising agent, organic acids, and osmolarity on succinic acid production by Escherichia coli AFP1842008Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    Using a low-cost medium Escherichia coli AFP184 has previously been reported to produce succinic acid with volumetric productivities close to 3 g L-1 h-1. At a total organic acid concentration of 30 g L-1 the productivity decreased drastically resulting in final succinate concentrations of 40 g L-1. The economical viability of biochemical succinic acid production would benefit from higher final succinic acid concentrations and volumetric productivities maintained at >2.5 g L-1 h-1 for an extended period of time. In the present work the effects of osmolarity and neutralising agent (NH4OH, KOH, NaOH, K2CO3, and Na2CO3) on succinic acid production by AFP184 were investigated. Highest concentration of succinic acid was obtained with Na2CO3, 75 g L-1. It was also found that the osmolarity resulting from succinate production and subsequent base addition, only marginally affected the productivity per viable cell. Organic acid inhibition due to the produced succinic acid on the other hand significantly reduced succinic acid productivity per viable cell. When using NH4OH productivity completely ceased at approximately 40 g L-1. Volumetric productivities remained at 2.5 g L-1 h-1 for 5 to 10 hours longer when using K- or Na-bases than when using NH4OH. However, loss of cell viability occurred, and together with the acid inhibition decreased the volumetric productivities. In this study it was demonstrated that by altering the neutralising agent it was possible to increase the period of high volumetric productivity in the anaerobic phase and improve the final succinic acid concentration by almost 100 %

  • 8.
    Helmerius, Jonas
    et al.
    Luleå tekniska universitet.
    Vinblad von Walter, Jonas
    Smurfit Kappa Kraftliner AB, Piteå, 941 86, Sweden.
    Rova, Ulrika
    Luleå tekniska universitet.
    Berglund, Kris K. A.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Hodge, David
    Production of value added chemicals from xylan extraction in a Kraft pulp mill and the effect on pulp quality2008Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    In the Kraft process hemicelluloses are lost in the cooking procedure to the black liquor stream, which is subsequently burnt in the recovery boiler to recover cooking chemicals and to produce steam and energy. Hemicelluloses have a low heating value compared to lignin and therefore recovery of hemicelluloses at an earlier stage of the Kraft process followed by biochemical conversionintohighvalue-conversion intohighvalue-into high value-added products might offer a muchbettereconomicopportunity.much better economic opportunityIn collaboration with the research and development department of Smurfit Kappa Kraftliner AB, Piteå, Sweden, alkali and water extractions of birch wood were performed under conditions compatible with the Kraft process, at different times, temperatures and alkali charges. The extraction conditions were set in a range suitable with the current pulp process at Smurfit Kappa Kraftliner. TherequirementsforprocessThe requirements for process configurations, based on either hot water or alkali extraction were also explored. ThexylanyieldsfromdifferentextractiontrialswereThe xylan yields from different extraction trials were measured and the chips from those extraction trials were cooked, refined and turned into sheets of paper. The effects on paper quality were compared with a reference pulp made from the same wooden chips. Recovered xylans from water extracted birch wood chips were subjected to secondary hydrolysis, enzymatic or sulphuricacid.sulphuric acidDetoxification of the hydrolysate with active carbon and regulation of pH were performed before fermentation. FermentationofthexyloseFermentation of the xylose hydrolysate to succinic acid was demonstrated by the use of thethe succinic acid producer Escherichia coli AFP184.

    Ladda ner fulltext (pdf)
    fulltext
  • 9. Helmerius, Jonas
    et al.
    Vinblad von Walter, Jonas
    Smurfit Kappa Kraftliner AB.
    Rova, Ulrika
    Berglund, Kris
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Hodge, David
    Production of value added chemicals from xylan extraction in a Kraft pulp mill and the effect on pulp quality2008Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    In the Kraft process hemicelluloses are lost in the cooking procedure to the black liquor stream, which is subsequently burnt in the recovery boiler to recover cooking chemicals and to produce steam and energy. Hemicelluloses have a low heating value compared to lignin and therefore recovery of hemicelluloses at an earlier stage of the Kraft process followed by biochemical conversion into high value-added products might offer a much better economic opportunity. In collaboration with the research and development department of Smurfit Kappa Kraftliner AB, Piteå, Sweden, alkali and water extractions of birch wood were performed under conditions compatible with the Kraft process, at different times, temperatures and alkali charges. The extraction conditions were set in a range suitable with the current pulp process at Smurfit Kappa Kraftliner. The requirements for process configurations, based on either hot water or alkali extraction were also explored. The xylan yields from different extraction trials were measured and the chips from those extraction trials were cooked, refined and turned into sheets of paper. The effects on paper quality were compared with a reference pulp made from the same wooden chips. Recovered xylans from water extracted birch wood chips were subjected to secondary hydrolysis, enzymatic or sulphuric acid. Detoxification of the hydrolysate with active carbon and regulation of pH were performed before fermentation. Fermentation of the xylose hydrolysate to succinic acid was demonstrated by the use of the succinic acid producer Escherichia coli AFP184.

    Ladda ner fulltext (pdf)
    fulltext
  • 10. Hodge, David
    et al.
    Andersson, Christian
    Helmerius, Jonas
    Vinblad von Walter, J.
    Rova, Ulrika
    Berglund, Kris
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Succinic acid production from forest based raw materials2008Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    Lignocellulosic biomass and particularly hemicellulose from the forest products industry represents a large reservoir of sugars with the potential to be converted to higher value products through bioprocessing. This presentation will cover several projects regarding the fractionation and conversion of lignocellulose to succinic acid, a potentially important platform molecule in the synthesis of a number of commodity and specialty chemicals. The first of these investigates the feasibility of integrating a hardwood hemicellulose sugar extraction step into a Kraft pulping process with the intention of utilizing the hemicellulose as a fermentation feedstock. The requirements on processing configurations for hemicellulose extraction and recovery are compared, and a number of experimental parameters affecting the extraction (alkali, temperature, time) are investigated. Pulp quality is an important property and hemicellulose extraction can result in negatively affect the strength of the paper, which is also investigated. The second portion of the work deals with the fermentation requirements for microbial conversion of dilute acid hydrolyzed softwood to succinic acid. In particular, activated carbon and overliming detoxifications were tested for the ability to remove fermentation inhibitors and improve the fermentability of the hydrolyzates.

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