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Residents living adjacent to forests commonly gather non-timber forest products (NTFPs) for income, nourishment, ailment treatment, firewood, religious reasons, and artefacts. This study focused on the locals’ perception of NTFP value addition in forest-adjacent communities in Ghana. To determine which NTFPs are collected, we interviewed 732 residents about their perception of value addition to the NTFPs collected and if value addition has impacted the commercialisation and quality of the products obtained from the forest. We found that 97.5% of those surveyed frequently visited the forest to gather different NTFPs. For example, mushrooms, snails, honey and others were the most collected. Also, most interviewees do not process or add value to the NTFPs collected from the forest; thus, adding value to these NTFPs could increase incomes in the future. Future research should focus on educating locals about the value addition to NTFPs, and processes for increasing the price of NTFPs by adding value and commercialising these products. Proper commercialising of NTFPs will help improve the lives of the locals.

The pulp and paper industry produces a diverse range of side-streams from multi-stage processes, but these remain underutilized despite their high potential for use as biofuels. This study investigated acetone-butanol-ethanol (ABE) fermentation by Clostridium acetobutylicum DSM 1731 from the side-streams of three different stages of the pulp and paper manufacturing process (PI, PII, and PIII). Biomass specimens with and without water washing were pretreated with 0.2% H2SO4 at 180 °C for 10 min, followed by enzymatic hydrolysis, to obtain fermentable sugars. The results showed that the produced ABE solvent concentrations were 12.8 g/L, 5.2 g/L, and 6.3 g/L from PI, PII, and PIII, respectively. The butanol yields of PI, PII, and PIII were 0.25, 0.18, and 0.19 g/g sugars, respectively. Among the tested side-streams, PI was shown to have potential as a feedstock for butanol production without prewashing prior to dilute acid pretreatment, enzymatic hydrolysis, and microbial fermentation.

This study investigated the effects of pretreatment using an acetone–butanol–ethanol (ABE) mixture with and without H2SO4 (H+) as a catalyst on sugar recovery from Salix schwerinii biomass. The sugar recovery was susceptible to both the temperature and the catalyst. Moreover, the relatively higher concentration of ABE (H+ABE4) at 200 °C yielded glucose recovery of 85.5% from the pretreated solid, higher than the recovery under other conditions. This result was mainly attributed to the compositional changes in the biomass, as the xylan and lignin were removed in large quantities by ABE pretreatment at 200 °C. Correspondingly, xylose recovery of 53.8% and glucose recovery of 12.1% were obtained from the liquid in which more sugar degradation products were formed. Ultimately, a fermentation broth containing a low concentration of ABE was successfully employed for pretreatment and showed great potential in producing fermentable sugars from S. schwerinii for biobutanol production.

In a greenhouse experiment, plant growth and copper (Cu) and zinc (Zn) uptake by four Salix cultivars grown in Cu and Zn contaminated soils collected from a mining area in Finland were test...

Simultaneous saccharification and fermentation (SSF) is a promising process for conversion of lignocellulosic materials to biofuels. However, the fermentation end products might inhibit the saccharification of lignocellulosics by cellulose-degrading enzymes. This study investigated the effects of acetone-butanol-ethanol (ABE) fermentation products on enzymatic hydrolysis of energy grasses. After addition of 5 g/L butanol during the hydrolysis, the glucose yields of pretreated Hybrid Pennisetum and Avicel apparently increased from 62.8% and 33.4% to 77.5% and 63.8%, respectively. The acetone and ethanol also showed the promotional effect at higher concentrations (>10 g/L), but the acetic acid and butyric acid exhibited slight inhibition on the hydrolysis. The accumulative effect of these solvents was observed by addition of solvent mixtures. The ABE solvents improved the activity of cellobiohydrolase (CBH) I and endoglucanase (EG) II remaining in hydrolysis solution, particularly butanol increased the activity of EG II to 142.8%, which probably contributed to the enhanced hydrolysis. Thus, the inhibition of ABE end products on hydrolysis of lignocellulosic materials during SSF was negligible, but instead, the promotion on enzymatic hydrolysis provided an opportunity for effective utilization of enzymes.

Soil and water contaminations are caused by rare earth elements (REEs) due to mining and industrial activities, that threaten the ecosystem and human health. Therefore, phytoremediation methods need to be developed to overcome this problem. To date, little research has been conducted concerning the phytoremediation potential of Salix for REEs. In this study, two Salix species (Salix myrsinifolia and Salix schwerinii) and two Salix cultivars (Klara and Karin) were hydroponically exposed to different concentrations of six-REE for 4 weeks. The treatments were: T1 (Control: tap water), T2 (La: 50 mg/L) and T3 (La 11.50 + Y 11 + Nd 10.50 + Dy 10 + Ce 12 and Tb 11.50 in mg L

European Union bioeconomy policy emphasizes that the production of renewable transportation fuels should replace fossil fuels as much as possible. In particular, the utilization of waste or side-stream lignocellulosic materials for fuel production is highly recommended. Moreover, future crises forcing a reliance on locally available sources for fuels and energy may become increasingly common. Barley straw, a common agricultural residue in northern Europe, is a potential raw material for bioalcohol production via fermentation. In this study, the technoeconomic and environmental sustainability of bioethanol and biobutanol production from barley straw were evaluated. When compared with fossil gasoline production and use, the greenhouse gas emissions reduction 77.6% and 72.1% were achieved for ethanol and butanol production, respectively. Thus, the emission reduction of 65% for biofuels demanded by the European Union renewable energy directive was achieved in both biofuel production processes evaluated. However, our results indicated that ethanol production from barley straw, a well-known and mature technology, was an economically feasible process (NPV positive, IRR 20%) but that butanol production with Clostridium species through acetone-butanol-ethanol fermentation has still technoeconomic challenges to overcome (NPV negative, IRR below 10%). This was mainly due to the low yield and high recovery costs of butanol.

Background. Sahara is one of the largest deserts in the world. The hard conditions especially high temperature and aridity lead to unique adaptation of organisms that could be a potential source of new metabolites. In this respect, two Saharan soils from El Oued Souf and Beni Abbes in Algeria were collected. The bacterial isolates were selected by screening the antibacterial, antifungal, and enzymatic activities. The whole genomes of the two native Saharan strains were sequenced to study the desert Streptomyces microbiology and ecology from genomic perspective. Results. The strains Babs14 (from Beni Abbes, Algeria) and Osf17 (from El Oued Souf, Algeria) were initially identified by 16S rRNA sequence as belonging to the Streptomyces genus. The whole genome sequencing of the two strains was performed by using Pacific Biosciences Sequel II technology (PacBio) and it showed that Babs14 and Osf17 have a linear chromosome of 8.00 Mb and 7.97 Mb, respectively. The number of identified proteins is 6910 in Babs14 and 6894 in Osf17. No plasmids were found in Babs14, whereas three plasmids were detected in Osf17 and no genome duplications were detected in the two strains. Although the strains have different phenotypes and are from different regions, they are slightly different from each other in protein sequence level but, differ more from their earlier published relatives. 29 biosynthetic gene clusters (BGCs) coding for secondary metabolites were predicted in each strain indicating antifungal, antibiotic, and other activities of Babs14 and Osf17. Moreover, many other BGCs were related to biosynthesis of factors needed in response to environmental stress in temperature, UV light and osmolarity. Conclusion. The genome sequencing of Saharan Streptomyces strains revealed factors that are related to their adaptation to an extreme environment and stress conditions. The genome information gives tools to study the ecological adaptation in desert environment and to explore the bioactive compounds of these microorganisms. The two whole genome sequences are among the first ones for the Streptomyces genus of Algerian Sahara. The present research was undertaken as a first step to explore more profoundly the desert microbiome.

This study assesses the wood waste generation, its management practices, and its effects on the forests in Ghana. The rate of logging in Ghana has increased and this can be attributed to the increase in the establishment of Sawmilling companies in the country. Increased in the installation of sawmilling companies has increased the sawn timber production. The use of outmoded milling machines has led to an increase in waste generation. An increase in production has led to an increase in the annual allowable cut in the country, which has overrun the limit of sustainable forestry. A qualitative research method was employed for the research work. A well-structured questionnaire was administered to the study to solicit the views of the wood industries about wood waste generation and its management practices. The study population comprised of 50 sawmilling companies. From the data collected, it was observed that most of the timber production companies do not know how to manage the waste generated and the waste is left un-utilized. In general 80% of the timber production companies responded that they have an idea of wood waste management but do not have the technical know-how to manage the waste. It was observed that 80% of the timber production companies do not manage the waste they generate during their operations. Wood shavings, sawdust, wood slabs, offcuts, branches, and others are left un-utilized. From the observations made in the visited sawmills, chunks of waste are generated on the site. The fact that the wood which is un-utilized (waste) and the wood, which is utilized as sold products, are equal in cost to the company which highlights the poor material and cost-efficiency. Wood industry materials and cost efficiency, together with waste management practices and their contribution to deforestation in the country, are discussed.

This study examined side-stream generation from Finnish forest industry comprising data from 19 sawmills, 1 plywood mill, 1 particleboard mill, 10 paper and board mills, 1 semi-mechanical mill, and 15 chemical pulp mills. A structured questionnaire survey was carried out for this study. The results revealed that the generation of side stream in sawmills, plywood mills, paper and board mills, mechanical pulp mills, and chemical pulp mills accounted for 42.2%, 56.1%, 23.8%, 30.7%, and 56% of round wood log input, respectively, and 91.2%, 135.5%, 42.2%, 44.7%, and 238.5% of the finished product, respectively. Woodchips, sawdust, and bark were recognized as the significant side streams in sawmills and plywood mills, whereas fiber sludge was found the main side stream in paper, board and mechanical pulp mills. In chemical pulp mills, black liquor was found the greatest side stream, which comprises 43% of the wood input and 183.3% of the finished product. The study estimated that in 2016, Finnish forest industry generated a total 27.7 million tons of side streams, consisting of 49.2% black liquor, 28.5% solid wood-based waste, 14.1% sludge, 4.4% ashes, and 3.8% others. A current use of these side streams and their future utilization potential is also discussed.

This study investigated whether the effectiveness of pretreatment is limited by a size reduction of Norway spruce wood in biobutanol production. The spruce was milled, chipped, and mashed for hydrogen peroxide-acetic acid (HPAC) and dilute acid (DA) pretreatment. Sugar recoveries from chipped and mashed spruce after enzymatic hydrolysis were higher than from milled spruce, and the recoveries were not correlated with the spruce fiber length. HPAC pretreatment resulted in almost 100% glucose and 88% total reducing sugars recoveries from chipped spruce, which were apparently higher than DA pretreatment, demonstrating greater effectiveness of HPAC pretreatment on sugar production. The butanol and ABE yield from chipped spruce were 126.5 and 201.2 g/kg pretreated spruce, respectively. The yields decreased with decreasing particle size due to biomass loss in the pretreatment. The results suggested that Norway spruce chipped to a 20 mm length is applicable to the production of platform sugars for butanol fermentation.

The dilute acid-catalyzed extraction of hemicellulosic monosaccharides from the short-rotation coppice Salix schwerinii E. Wolf was optimized to find a balance between the yields of fermentable monosaccharides and sugar degradation products for non-detoxified acetone-butanol-ethanol fermentation with Clostridium acetobutylicum. At the same time, the cellulosic and lignin fractions were kept as intact as possible for further refining. The highest xylose and glucose yields in the liquid prehydrolysate were 65% and 9.45% of their respective original content at a combined severity of 2.29. Increased concentrations of glucose and sugar degradation products in the liquid prehydrolysates were detected with an increasing pretreatment temperature and combined severity, while the acid-insoluble lignin remained stable. During the fermentation of the non-detoxified liquid prehydrolysate with grain starch as the supplement, 66% of the xylose was utilized, and the butanol and acetone-butanol-ethanol yields were 0.22 g/g and 0.35 g/g monosaccharides, respectively, in the fermentation medium. The results suggested that the hemicellulose in S. schwerinii can be separately extracted as a side stream and utilized for butanol fermentation with starch-based materials without a separate detoxification stage.

New energy crops adapted to northern conditions of Europe can broaden the portfolio of agricultural based biofuel options in an area with currently few alternatives. This study evaluates two energy crops, giant knotweed (Fallopia sachalinensis var. ‘Igniscum’) and Virginia mallow (Sida hermaphrodita), as possible biomass feedstocks for biofuels in southern Finland. The collected data includes yield productivity, physical and chemical properties, and energy content. The dry matter yield of giant knotweed ranges from 5.41 odt·ha−1 to 27.67 odt·ha−1, whereas Virginia mallow ranges from 6.72 odt·ha−1 to 16.72 odt·ha−1. Pellets from both crops meet the requirements regarding standards. Giant knotweed presents a bulk density of 677.71 kg·m−3 and Virginia mallow 725.18 kg·m−3. The results of mechanical durability of giant knotweed do not exceed the minimum threshold of the standards, with 96.73 w-%, while Virginia mallow is 92.86 w-%. The analysis of the ash content results in 1.5% for giant knotweed and 2.19% for Virginia mallow. The quantities of chlorine (Cl) and sulphur (S) are below the recommended thresholds. Finally, the energy content with moisture content of 5 w-% of giant knotweed and Virginia mallow were 19.97 MJ·kg−1 and 19.68 MJ·kg−1, respectively. Both crops prove are valid alternatives in the climatic and soil conditions of Northern Europe.

This study assessed the energy and environmental impacts in terms of second-generation (2G) bioethanol production, renewable electricity generation and greenhouse gas (GHG) emissions reduction potential of surplus rice straw (SRS) in India. National rice production database, and standard procedures for life cycle assessment of rice straw to 2G bioethanol production using two different pretreatment technologies namely, dilute acid (DA) and steam explosion (SE) pretreatments were explored for the analysis. Two scenarios (benchmark and resource-efficient) were constructed to evaluate the availability of SRS and to determine the potential from 2020 to 21 to 2030–31. Under benchmark for the year 2030–31, the potential from SRS using DA and SE pretreatment methods for the production of 2G bioethanol and the surplus renewable electricity generation were estimated to be 10,547 and 11,165 million L; and 5295 and 6928 GWh, respectively, and the corresponding GHG emissions reduction potential were assessed to be 11,954 and 14,375 kt CO2eq., respectively while generated renewable electricity replaces crude oil-driven grid electricity, and 11,498 and 14,498 kt CO2eq., respectively while generated renewable electricity replaces coal-driven grid electricity. The study revealed that both the availability of SRS and the choice of pretreatment method play decisive roles in the determination of its potential.

Neutralization is essential to maintain the pH for enzymatic hydrolysis of cellulose followed by fermentation of biofuels. This study investigated the effect of salts formed during the neutralization on the enzymatic hydrolysis of cellulosic materials and acetone–butanol–ethanol (ABE) fermentation. The results showed that the formed Ca-citrate salt considerably decreased the glucose release by 26.9% and 26.1% from Avicel and sulfuric acid-pretreated hybrid Pennisetum, respectively, which was probably due to the unproductive adsorption of cellulases by Ca-citrate solids. On the other hand, the formed soluble Na and Ca salts severely inhibited ABE fermentation, thereby decreasing the ABE concentration from 12.8 g L−1 to 0–10.7 g L−1 in different degrees, but no or slight inhibition was observed when the Ca salts formed as precipitates. In particular, Ca-sulfate did not show apparent inhibition of both hydrolysis and fermentation. Therefore, the selection of suitable pretreatment and neutralizing reagents is an alternative way to avoid process inhibition in biofuel production from lignocellulosic materials.

In a greenhouse experiment, plant growth and copper (Cu) and zinc (Zn) uptake by four

In many Baltic regions, short-rotation willow (Salix spp.) is used as a vegetation filter for wastewater treatment and recycling of valuable nutrients to upsurge bioeconomy development. In this context, a four-year field trial (2016–2019) was carried out near a wastewater treatment plant in eastern Finland (Outokumpu) to investigate the effect of the processed wastewater (WW) on biomass production as well as the nutrients uptake capability (mainly N and P) by a willow variety (Salix schwerinii). Results indicated that WW irrigation expressively increased the willow diameter growth and biomass yield around 256% and 6510%, respectively, compared to the control treatment site (without WW). The willow was also able to accumulate approximately 41–60% of the N and 32–50% of the P in two years (2018–2019). Overall, willow showed a total 20% mortality rate under WW irrigation throughout the growing periods (2017–2019) as compared to control (39%). The results demonstrate that willow has the potential to control eutrophication (reducing nutrients load) from the wastewater with the best survival rate and can provide high biomass production for bioenergy generations in cold climatic conditions.

This paper provides an overview of different methods of assessing the trace metal (TM) contamination status of sediments affected by anthropogenic interference. The geochemical background determination methods are also described. A total of 25 papers covering rivers, lakes, and retention tanks sediments in areas subjected to anthropogenic pressure from the last three years (2019, 2020, and 2021) were analysed to support our examination of the assessment measures. Geochemical and ecotoxicological classifications are presented that may prove useful for sediment evaluation. Among the geochemical indices, several individual pollution indices (CF, Igeo, EF, Pi (SPI), PTT), complex pollution indices (PLI, Cdeg, mCdeg, Pisum, PIAvg, PIaAvg, PIN, PIProd, PIapProd, PIvectorM, PINemerow, IntPI, MPI), and geochemical classifications are compared. The ecotoxicological assessment includes an overview of Sediment Quality Guidelines (SQG) and classifications introduced nationally (as LAWA or modified LAWA). The ecotoxicological indices presented in this review cover individual (ERi) and complex indices (CSI, SPI, RAC, PERI, MERMQ). Biomonitoring of contaminated sites based on plant bioindicators is extensively explored as an indirect method for evaluating pollution sites. The most commonly used indices in the reviewed papers were Igeo, EF, and CF. Many authors referred to ecotoxicological assessment via SQG. Moreover, PERI, which includes the toxic response index, was just as popular. The most recognised bioindicators include the Phragmites and Salix species. Phragmites can be considered for Fe, Cu, Cd, and Ni bioindication in sites, while Salix hybrid cultivars such as Klara may be considered for phytostabilisation and rhizofiltration due to higher Cu, Zn, and Ni accumulation in roots. Vetiveria zizanoides demonstrated resistance to As stress and feasibility for the remediation of As. Moreover, bioindicators offer a feasible tool for recovering valuable elements for the development of a circular economy (e.g., rare earth elements).

The sustainability of transportation biofuel production value chains is under discussion as a consequence of the implementation of the European Union Bioeconomy Strategy and renewable energy production. Greenhouse gas emissions from the biomass produced for biofuel, and the energy required during the production process are, in many cases, greater than the emission reductions from the biofuels that are produced and used to replace fossil fuels. In this study, the sustainability of bioethanol production from short rotation coppice Salix schwerinii was considered from cultivation and harvesting to biofuel production and distribution. The sustainability of the full value chain was evaluated according to the European Union Renewable Energy Directive and calculations of greenhouse gas emission savings (%) from biofuel production were compared to a reference fossil fuel (gasoline). For comparison, four bioethanol production scenarios were developed, and specific attention was focused on the utilization of waste-based organic fertilizers (for biomass production) and on carbon dioxide capture at the fermentation stage, and their effects on value chain greenhouse gas emissions. Based on our evaluation, Salix bioethanol production achieved 60% emission savings compared to the fossil reference (requirement for installations that will commence operations until end of December 2020). When waste based organic fertilizers were used in the Salix biomass production, 65% emission savings were achieved (requirement for the installations that will commence operations from 2021). Moreover, the value chain sustainability and greenhouse gas emissions balance were improved by the carbon dioxide captured during the bioethanol fermentation stage.

Fast pyrolysis oil (FPO) produced from short-rotation willow was characterized by using high-resolution Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometry and various bulk chemical analyses. The pyrolysis experiments were carried out on a bench-scale bubbling fluidized bed pyrolysis reactor operating at the temperature of 500 °C. The resulting pyrolysis oil was a single-phase liquid with relatively low oxygen content and had pH and total acid number values of 3.0 and 129 mg/g, respectively. A wealth of compositional information of the willow FPO was obtained using FT-ICR MS in combination with electrospray ionization (ESI) and atmospheric-pressure photoionization (APPI) techniques. While ESI preferentially ionized acidic extractives, small phenolics and anhydrosugars, APPI ionized clearly larger compounds, including neutral lipophilic extractives, triterpenoids and high molecular mass pyrolytic lignin, most of which are beyond conventional gas chromatography–mass spectrometry analyses.

Salix schwerinii was tested in a pot experiment to assess plant growth performance i.e., relative height and dry biomass and the potential for heavy metal uptake in soils polluted with chromium, zinc, copper, nickel and total petroleum hydrocarbons. The soil used in the pot experiment was collected from a landfill area in Finland. Peat soil was added at different quantities to the polluted soil to stimulate plant growth. The plants were irrigated with tap water or processed water (municipal waste water) to further investigate the effects of nutrient loading on plant biomass growth. The soil was treated at two pH levels (4 and 6). The results showed that the addition of 40–70% peat soil at pH 6 to a polluted soil, and irrigation with processed water accelerated plant growth and phytoextraction efficiency. In the pot experiment, Salix grown in chromium, zinc, copper, nickel and total petroleum hydrocarbons -contaminated field soil for 141 days were unaffected by the contaminated soil and took up excess nutrients from the soil and water. Total mean chromium concentration in the plant organs ranged from 17.05 to 250.45 mg kg −1 , mean zinc concentration ranged from 142.32 to 1616.59 mg kg −1 , mean copper concentration ranged from 12.11 to 223.74 mg kg −1 and mean nickel concentration ranged from 10.11 to 75.90 mg kg −1 . Mean chromium concentration in the plant organs ranged from 46 to 94%, mean zinc concentration ranged from 44 to 76%, mean copper concentration ranged from 19 to 54% and mean nickel concentration ranged from 8 to 21% across all treatments. Under the different treatments, chromium was taken up by Salix in the largest quantities, followed by zinc, copper and nickel respectively. Salix also produced a moderate reduction in total petroleum total petroleum hydrocarbons in the polluted soil. The results from the pot experiment suggest that Salix schwerinii has the potential to accumulate significant amounts of chromium, zinc, copper and nickel. However, long term research is needed to verify the phytoextraction abilities of Salix observed in the pot experiment.

The present study investigated the ability of pressurized microwave pretreatment to convert softwood lignocellulose to fermentable monosaccharides. Norway spruce lignocellulose was subjected to microwave pretreatment (600 and 1200 W) under high pressure at different temperatures. Microwave pretreatment at mild acid concentrations (0.05–0.1 % H2SO4), temperatures of 170 and 200 °C, and a very short incubation time (5 min) released 84–100 % of hemicellulosic monosaccharides (mannose, galactose, and xylose). In addition, minimal amounts of degradation products (5-(hydroxymethyl)-2-furaldehyde, levulinic acid) were formed. The highest yield of fermentable sugars was 75 %, after both the pressurized microwave pretreatment with conditions 0.05 % H2SO4/600 W/200 °C/5 min and enzymatic hydrolysis with 20 FPU Celluclast 1.5 L, 400 nkat of Novozyme 188, and polyethyleneglycol (PEG) 4000 (0.3 g/g of pretreated material). Results showed that already 0.05 % H2SO4 used in microwave pretreatment could effectively liberate hemicellulose monosaccharides without serious monosaccharide degradation and form a basis for enzymatic hydrolysis.

The aim of the study was to evaluate the current level of awareness, implementation and need for knowledge of game-oriented forest management (GOFM) among forest owners and professionals. This information is necessary to understand the grounds for improving awareness and implementation of new forest management guidelines and to evaluate suitable policy instruments for the future. The study joins the body of research on innovation diffusion and institutional adaptation, in regard to new forest management methods. Our results from Finland indicated that a high proportion of forest owners have not adopted GOFM, despite the information provided. A wider implementation of the method might require other knowledge dissemination methods, such as providing tangible examples and peer learning to forest owners. The role of forest professionals as change agents was seen to be important for the generalization of GOFM among forest owners and inside institutions. The observed level of awareness of GOFM and its implementation among forest owners, and the engagement of professionals reflects a situation where the informing process is ongoing, and where the forestry advisors need tools to engage forest owners more effectively. At the same time, it is difficult to estimate the effectiveness of the voluntary-based approach of GOFM. In this study, the double sampling design removed volunteer bias and increased the reliability of the results.

In this study, the utilization of silicalite–1 membrane pervaporation for butanol recovery from an acetone-butanol-ethanol (ABE) fermentation broth solution was investigated. In particular, the negative effect of butyric acid on the pervaporation performance was tested. The presence of butyric acid was observed to decrease both the butanol flux and selectivity of the membrane. Clear relation between the severity of the decreased performance and the amount of butyric acid was observed. Increasing the pH of the feed solution was observed to improve butanol pervaporation in the presence of butyric acid. In pervaporation of ethanol, butanol and butyric acid, there are significant interactions in adsorption and diffusion between the components. The presence of butanol restricts the permeation of ethanol while the butanol permeation is restricted by the presence of butyric acid. The effects likely arise from adsorptive competition and are further amplified due to the rates of diffusion. In addition, butyric acid exposure may change the membrane properties over time, although they may be restored by heating. The results suggest that the selective recovery of butanol with a silicalite–1 membrane is not feasible if the concentration of butyric acid is significant and the pH value in the solution is low.

Rhizophora spp. are grown for wood charcoal production in many tropical estuaries and coastal areas. However, a lack of species-level information stands in the way of promoting this resource for sustainable practices. The present study investigated management practices and aboveground biomass (AGB) production patterns of Rhizophora apiculata plantations in the Yeesarn area of Samut Songkhram Province, Central Thailand. Interviews of farmers and a field survey were main instruments for collecting and analyzing of the data. It was found that farmers collect mature propagules locally and use traditional knowledge for maintenance of the plantation including site preparation and planting. Beating-up and weeding are the main operations applied in establishing a plantation; otherwise, little effort is directed towards post-planting maintenance. The plantation was reforested in a harvesting rotation of 8 to 15 years. Observed stand growth in terms of annual turnover rate (ATR) of height and diameter was highest in a 12-year old plantation; 0.82 m/year and 0.46 cm/year, respectively. Highest AGB production, stem wood volume (SWV), and commercial wood volume (CWV) were observed in a 14-year old plantation; 201.95 tonnes/ha, 181.49 m3/ha, and 178.98 m3/ha, respectively. Growth and productivity patterns indicate that the plantation has a high yield potential in terms of wood biomass production.

This study aims to improve enzymatic sugar production from dilute sulfuric acid-pretreated barley straw for acetone–butanol–ethanol (ABE) fermentation. The effects of additive xylanase and surfactants (polyethylene glycol [PEG] and Tween) in an enzymatic reaction system on straw hydrolysis yields were investigated. By combined application of 2 g/100 g dry-matter (DM) xylanase and PEG 4000, the glucose yield was increased from 53.2% to 86.9% and the xylose yield was increased from 36.2% to 70.2%, which were considerably higher than results obtained with xylanase or surfactant alone. The ABE fermentation of enzymatic hydrolysate produced 10.8 g/L ABE, in which 7.9 g/L was butanol. The enhanced sugar production increased the ABE yield from 93.8 to 135.0 g/kg pretreated straw. The combined application of xylanase and surfactants has a large potential to improve sugar production from barley straw pretreated with a mild acid and that the hydrolysate showed good fermentability in ABE production.

This study aims to efficiently use hemicellulose-based biomass for ABE (acetone–butanol–ethanol) production by co-fermentation with starch-based biomass. Two processes were investigated: (I) co-fermentation of sugars derived from hemicellulose and starch in a mixture of barley straw and grain that was pretreated with dilute acid; (II) co-fermentation of straw hemicellulosic hydrolysate and gelatinized grain slurry in which the straw was pretreated with dilute acid. The two processes produced 11.3 and 13.5 g/L ABE that contains 7.4 and 7.8 g/L butanol, respectively. In process I, pretreatment with 1.0% H 2 SO 4 resulted in better ABE fermentability than with 1.5% H 2 SO 4 , but only 19% of pentoses were consumed. In process II, 95% of pentoses were utilized even in the hemicellulosic hydrolysate pretreated with more severe condition (1.5% H 2 SO 4 ). The results suggest that process II is more favorable for hemicellulosic biomass utilization, and it is also attractive for sustainable biofuel production due to great biomass availability.

This study aims to improve acetone-butanol-ethanol production from the hydrolysates of lignocellulosic material by supplementing starchy slurry as nutrients. In the fermentations of glucose, xylose and the hydrolysates of Salix schwerinii, the normal supplements such as buffer, minerals, and vitamins solutions were replaced with the barley starchy slurry. The ABE production was increased from 0.86 to 14.7 g/L by supplementation of starchy slurry in the fermentation of xylose and the utilization of xylose increased from 29% to 81%. In the fermentations of hemicellulosic and enzymatic hydrolysates from S. schwerinii, the ABE yields were increased from 0 and 0.26 to 0.35 and 0.33 g/g sugars, respectively. The results suggested that the starchy slurry supplied the essential nutrients for ABE fermentation. The starchy slurry as supplement could improve the ABE production from both hemicellulosic and cellulosic hydrolysate of lignocelluloses, and it is particularly helpful for enhancing the utilization of xylose from hemicelluloses., final draft, peerReviewed

In this study, pretreatment liquor of acid-stored green and yellowish barley silage was used for fermentative acetone–butanol–ethanol (ABE) production. Further, the catalytic oxidation of biobutanol over Pt catalysts was studied to investigate the behaviour of butanol as a fuel in the combustion engine. After the hydrothermal treatment of green and yellowish barley silage followed by enzymatic hydrolysis, approximately 88% and 100% of the available sugars were recovered, respectively. Batch fermentations of pretreatment barley silage liquor, supplemented with gelatinised barley grain, showed good fermentability with total ABE concentrations of 9.0 g/L and 10.9 g/L. Butanol yields of 0.20, 0.17 and ABE yields of 0.28, 0.26 (g/g monosaccharide) were obtained, respectively. In catalytic activity measurements, the conversion of biobutanol became appreciable in the 120–140 °C range, whereas conversions greater than 95% were obtained over 200 °C. Selectivities were also high, although formation of by-products, such as butyraldehyde, was observed.

Lignocellulosic biomass (LCB), the most abundant renewable feedstock for bioenergy generation, is commonly converted to second generation bioalcohols, the main drop-in fuels for petroleum gasoline, through three technologies based on sugar, carboxylic acid and syngas platforms. The hybridization of either any two or three platforms altogether is a novel concept aimed at improvement of yield and quality (high heating value) of bioalcohols. This article reviews the present status of the integration techniques of hybrid platforms with an overall assessment of their advancement with respect to their individual counterpart as well as the challenges involved. It has been indicated that to extract the maximum benefit of hybridization, research studies should be spurred in the fields of kinetic analysis of all thermochemical and biochemical processes, microbial interaction, optimization of process parameters (pH, temperature), performance analysis of engine for the utilization of mixed product bioalcohols, sustainability analysis through the development of mathematical models for lab-scale operations and process simulation models for large scale units along with life cycle assessment. Moreover, pyrolysis of LCB has been identified as a unique central process for the supply of all intermediate compounds, namely, sugar, carboxylic acid and syngas during the hybrid networking of three platform technologies. In this context, the scheme of CONVER-B, a joint research project under the INNO-INDIGO partnership program, aiming at sustainable integration of the platforms to produce bio-alcohols from LCBs leaving zero effluent simultaneously with carbon sequestration potential has been introduced and discussed.

The present study investigated the phytoextraction ability of Salix schwerinii E.L. Wolf enhanced with an application of the chelate N10O. Salix schwerinii were grown in garden soil that was also amended with Cu (400 mg kg−1), Ni (30 mg kg−1) and Zn (200 mg kg−1). Multiple doses of N10O were applied to the treatments as follows: Cu (3.45 g and 6.9 g), Ni (1.2 g and 2.4 g), and Zn (1.45 g and 2.9 g). Furthermore, N10O doses were also repeated with the control soil. The effect of N10O on height growth, biomass production, ecophysiological attributes, and the accumulation of metals (Cu, Ni, and Zn) in Salix in polluted soils was studied. Compared to the control, the total metal concentrations in S. schwerinii growing in the soils amended with N10O increased substantially by up to 895% for Cu, 324% for Ni and 722% for Zn. The translocation factor (TF) and bioconcentration factor (BF) values for S. schwerinii increased with the application of N10O and varied from 0.30–1.01 for Cu, 0.45–1.25 for Ni, and 4.40–5.89 for Zn, whereas, BF values varied from 0.60–1.15 for Cu, 0.80–1.50 for Ni, and 4–8 for Zn. This study indicated that S. schwerinii can be used for phytoextraction of Cu, Ni and Zn from contaminated soils. However, further research is needed to examine the phytoextraction potential of other Salix species using N10O to remediate soils polluted with various toxic metals.

Large numbers of Finnish lakes accumulate biomass sediments due to large nutrient inputs from forest areas, agricultural and industrial activities. The theoretical biofuel production potential was studied for lake bottom biomass from mesotrophic (ML) and eutrophic lakes (EL) in eastern Finland. Methane potentials of the EL and ML biomass were 136.6 ml g−1 volatile solid and 38.9 ml g−1 volatile solid, respectively. The estimated ethanol yields of the EL and ML biomass from fermentation were 137 l tonne−1, and 40 l tonne−1, whereas the yields from mixed alcohol synthesis after gasification were 244.5 l tonne−1 and 57.1 l tonne−1, respectively. The ash from both lake bottom biomass contained harmful elements below the detectable limit, and therefore, could be used as fertilizer. Techno-economic estimation showed that bioethanol production from the fermentation of EL biomass is the most profitable process and is a potential non-food lignocellulosic biomass source for the biorefining industry.

In this work, carbon nanotubes (CNTs) functionalized by acidic amino acids were used as a framework, which aims to form a mimetic structure of an active site of the glycoside hydrolases. It was demonstrated that the glycosidic bonds of the disaccharides were cleaved by the fabricated biofunctionalized CNTs. It was implied that the number of carboxyl groups and their individual pKa values in the amino acids, and the distance between the NH2 and the side chain carboxyl groups of the amino acid are predominant factors for determining the reaction efficiency and the optimum pH. It was suggested that glutamic acid functionalized CNTs framework showed the highest efficiency in the cleavage of glycosidic bond of cellobiose than other acidic biomolecules. It was also suggested that the glutamic acid functionalized CNT framework showed preference to the types of glycosidic bonds in the following order: β-1,2-glycoside > β-1,4-glycoside > α-1,4-glycoside [Formula: see text] α-1,1-glycoside bond.

This study investigated the effects of pretreatment conditions, dilute sulfuric acid concentration and treatment time, on the carbohydrate solubility of a mixture of barley straw and grain. The conditions were expressed as combined severity (CS) to evaluate sugar recovery from pretreated samples. Enzymatic hydrolysates from the lignocellulose pretreatment residues were also included to the results. CS was positively correlating with glucose recovery in all conditions, but in higher acid concentrations CS did not predict xylose recovery. It appeared that the residual xylan better indicate the xylose release. An optimal fermentable sugar yield from the mixture of barley straw and grain was obtained by maintaining the CS at around 1.38, corresponding to an overall glucose yield of 96% and a xylose yield of 57%.