The main objective has been to describe different cases of the methanol production from steel-work off gases (Coke oven gas and Basic oxygen furnace gas) and biomass based synthesis gas. The SSAB steel mill in the town of Luleå, Sweden has been used as a basis to analyze four different methanol production cases. The studied biomass gasification technology is based on a fluidized bed gasifier unit, where the production capacity is determined from case to case coupled to the heat production required to satisfy the local district heating demand. Critical factors are the integration of the gases with availability to the synthesis unit, to balance the steam system of the biorefinery and to meet the district heat demand of Luleå. For each case, the annual production potential of methanol, the overall production efficiencies and the effects on the total steel plant have been estimated.

The production of nitrogen fertilizers are almost exclusively based on fossil feedstocks such as natural gas and coal. Nitrogen fertilizers are a necessity to maintain the high agricultural production that the world's population currently demands. Ammonia produced from nonfossil-based feedstocks would enable renewable production of ammonia. Renewable feedstocks are one thing, but perhaps even more important in the future are the security of supply that decentralized production enables. In this study, the technoeconomic evaluation of production of ammonia from various renewable feedstocks and for several plant sizes was investigated. The feedstocks included in this study are gridbased electricity produced from wind power, biogas, and woody biomass. The feedstocks differed in exergy, and to make a fair comparison, the electric equivalence ratios method was used. The results showed that the energy consumption for biogas and electricity is the same at 42 GJ/ tonne ammonia. When using the electric equivalence comparison for the same cases, the results are 26 and 42 GJ/ tonne, respectively. Biomass-based production has an energy consumption of 58 GJ/tonne and 31 GJ/tonne when using the electric equivalence comparison, which should be compared with the industrial average of 37 GJ (or 21 GJ electric equivalence) per tonne of ammonia. Monte Carlo simulations were used to vary the inputs to the process to evaluate the production cost. The ammonia production cost ranged from $680 to 2300/tonne ammonia for the various cases studied.

Base-catalysed depolymerisation of lignin using sodium hydroxide has been shown to be an effective approach towards exploiting industrial (technical) lignins within the pulp and paper industry. In the present work, a pine kraft lignin (Indulin AT) which is precipitated from black liquor of linerboard-grade pulp was depolymerised via base catalysis to produce lowmolecular-mass aromatics without any organic solvent/capping agent in a continuous-flow reactor setup for the first time. The catalytic conversion of lignin was performed/screened at temperatures varying from 170 to 250°C, using NaOH/lignin weight ratio ≈ 1 with 5 wt% lignin solids loadings for residence times of 1, 2 and 4 min, respectively, with comprehensive characterisation of substrate and produced reaction mixtures. The products were characterised using size exclusion chromatography (SEC), nuclear magnetic resonance spectroscopy (NMR) and supercritical fluid chromatography-diode array detector-tandem mass spectrometry (SFC-MS). The optimum operating conditions for such depolymerisation appeared to be at 240°C and 30 h −1 , yielding the highest concentration of low-molecular-weight phenolics below the coking point. It was also found that the depolymerised lignin products exhibited better chemical stability during long-term storage at lower temperatures (~4°C).

Bio-based 5-hydroxymethylfurfural (5-HMF) and its derivatives have attracted enormous attention due to their valuable market potential. Production of pure 5-HMF is challenging owing to the high reactivity of its functional...

No abstract

One way of valorizing the lignin waste stream from the pulp and paper industries is depolymerizing it into low-molecular-mass compounds (LMMC). However, a common problem in the depolymerization of Kraft lignin is the low yields of small aromatic molecules obtained. In the present work, the combination of the repeated depolymerization of lignin and the separation of LMMC from depolymerized lignin to upgrade them into value-added chemicals was studied. In so doing, we investigated the possibility of depolymerizing black liquor retentate (BLR). The base-catalyzed depolymerization of BLR was performed using a continuous flow reactor at 170–210 °C, with a 2 min residence time. The results obtained indicate that BLR can be depolymerized effectively under the experimental conditions. Depolymerized lignin LMMC can be successfully separated by a GR95PP membrane, and thus be protected from repolymerization. Through combining membrane filtration with base-catalyzed depolymerization, more than half of the lignin could be depolymerized into LMMC. Around 46 mg/g of lignin monomers (guaiacol, vanillin, acetovanillone, and acetosyringone), which can potentially be upgraded to high-valued chemicals, were produced. On the basis of our results, we suggest use of a recycling Kraft lignin depolymerization and filtration process for maximizing the production of LMMC under mild alkaline conditions.

PostprintThis is the accepted version of a paper published in Fuel. This paper has been peer-reviewed but does not include the final publisher proof-corrections or journal pagination.Citation for the original published paper (version of record):Svensson, H., Tunå, P., Hulteberg, C., Brandin, J. (2013) Modeling of soot formation during partial oxidation of producer gas. Fuel AbstractSoot formation in a reverse flow partial oxidation reactor for reforming of gasifier producer gas has been studied. The process was modeled using a detailed reaction mechanism to describe the kinetics of soot formation. The numerical model was validated against experimental data from the literature and showed good agreement with reported data. Nine cases with differing composition was simulated in order to study the effect of water content, hydrogen content and methane content of the gas. The CO and CO 2 content was also varied to study its effect on soot formation as well as the tar content of the gas. The results show that steam and hydrogen content of the inlet gas had lower influence on the soot formation than expected. The methane content greatly influenced the soot formation. Results also showed that increasing the CO 2 content of the gas reduces the amount of soot formed and gives a higher energy efficiency and methane conversion. For the case with no tars in the ingoing gas the soot formation was significantly reduced. It can be concluded that removing the tars in an energy efficient way, prior to the partial oxidation reactor, will greatly reduce the amount of soot formed. Further investigation of tar reduction is needed and experimental research of this process is undergoing.

An ew generation of N-heterocyclic carbenep alladium(II) complexes containing vinyl groups in different positions in the backbone of the N-heterocycle have been developed. The fully characterised monomers were copolymerised with divinylbenzenet of abricate robustp olymer supported NHC-Pd II complexes and these polymers were applied as heterogeneousc atalysts in directed CÀHh alogenation of arenes with ap yridine-type directing group.T he catalysts demonstrated medium-high catalytic activity with up to 90 %c onversion and 100 %s electivity in chlorination. They are heterogeneousa nd recyclable (at least six times) with no significant leachingo fp alladium in batch mode catalysis. The best catalyst was also applied under continuous flow conditions where it disclosed an exceptional activity (90 % conversion)a nd 100 %s electivity for the mono-halogenated product for at least sixd ays, with no leachingo fp alladium, no loss of activity and an ability to maintain the original oxidationstate of Pd II .[a] M.Supporting information and the ORCID identification number(s) for the author(s) of this articlecan be found under: https://doi.