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This paper proposes an easy and sustainable method to prepare high-sorption capacity biobased adsorbents from wood waste. A biomass wood waste (spruce bark) was employed to fabricate a composite doped with Si and Mg and applied to adsorb an emerging contaminant (Omeprezole) from aqueous solutions, as well as synthetic effluents loaded with several emerging contaminants. The effects of Si and Mg doping on the biobased material's physicochemical properties and adsorptive performance were evaluated. Si and Mg did not influence the specific surface area values but impacted the presence of the higher number of mesopores. The kinetic and equilibrium data presented the best fitness by the Avrami Fractional order (AFO) and Liu isotherm models, respectively. The values of Qmax ranged from 72.70 to 110.2 mg g-1 (BP) and from 107.6 to 249.0 mg g-1 (BTM). The kinetic was faster for Si/Mg-doped carbon adsorbent, possibly due to different chemical features provoked by the doping process. The thermodynamic data showed that the adsorption of OME on biobased adsorbents was spontaneous and favorable at four studied temperatures (283, 293, 298, 303, 308, 313, and 318 K), with the magnitude of the adsorption correspondent to a physical adsorption process (ΔH° < 2 kJ mol-1). The adsorbents were applied to treat synthetic hospital effluents and exhibited a high percentage of removal (up to 62%). The results of this work show that the composite between spruce bark biomass and Si/Mg was an efficient adsorbent for OME removal. Therefore, this study can help open new strategies for developing sustainable and effective adsorbents to tackle water pollution.

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With an increase in climate and environmental issues awareness, the use of waste of various types has gained increased visibility, acknowledging that wastes are any and all kinds of unused materials from the production process or after using the final product for its intended purpose. The use of wastes to produce alternative cement materials is an alternative to reduce the use of natural resources. Forestry residues, ash, plastic residues, LDPE/Al composites, and geopolymer materials are some of the possible residues used for the partial replacement of cement materials. The objective of this research is to establish how these materials relate to each other, based on a topic review and how they can contribute towards sustainability. The study was performed on several scientific article search engines, in which the keywords 'Carton Packages', 'Wood Waste' and 'Geopolymers' were inserted, and then a refinement was carried out using the term 'Cement Materials'. Such analysis allowed the generation of information related to publication numbers, countries, research areas, as well as publication types. Co-authorship networks of organization, co-citation of references, co-occurrence of keywords, among others, were also plotted. Through this bibliometric analysis, it was possible to reveal the structure of the research, analyse the developments and predict the future directions for the research regarding the use of residues in the production of sustainable Portland cement composites.

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Cedrela odorata L. is a plant species from the Meliaceae family that is cultivated for timber production. Although the C. odorata essential oil (EO) contains mainly sesquiterpenes, its insecticidal potential is unknown. The lipophilic properties and high degradation capacity of EOs have limited their application for use in pest control. However, the currently available knowledge on the nanoemulsification of EOs, in addition to the possibility of improving their dispersion, would allow them to prolong their permanence in the field. The objective of the present work was to develop a nanoemulsion of the C. odorata EO and to evaluate its larvicidal activity against Spodoptera frugiperda. The EO was obtained by the hydrodistillation of C. odorata dehydrated leaves, and the nanoemulsion was prepared with non-ionic surfactants (Tween 80 and Span 80) using a combined method of agitation and dispersion with ultrasound. The stability of the nanoemulsion with a droplet diameter of <200 nm was verified in samples stored at 5 °C and 25 °C for 90 days. Both the C. odorata EO and its corresponding nanoemulsion presented lethal properties against S. frugiperda. The results obtained provide guidelines for the use of wood waste to produce sustainable and effective insecticides in the fight against S. frugiperda. In addition, considering that a phytochemical complex mixture allows the simultaneous activation of different action mechanisms, the development of resistance in insects is slower.

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Urban forestry generates a huge amount of waste worldwide, resulting from the processes of pruning and suppression. Disposal in landfills reduces the useful life of these facilities and forgoes the possibility of generating income from the waste. This study investigated the manufacture of toys as a strategy to valorize urban forestry waste. For this, physical-mechanical, chemical (extractive), color and shape characterizations were performed for three species of urban trees commonly planted in Brazil, a region of Neotropical forests. Toy prototypes were developed and manufactured from wood waste. Regarding color, all studied species showed high value of the variable b*, which refers to the blue-yellow axis. Handroanthus heptaphyllus wood had the highest values of basic density (0.706 g.cm-3) and Janka hardness (1142, 1027 and 1669 kgf.cm-2 for radial, tangential and transverse directions, respectively), and had the lowest volumetric shrinkage (11.38%). The lowest content of total extractives was measured in Handroanthus heptaphyllus, 6.33%, and the greatest content was found in Spathodea campanulata, 7.01%. The average value suggested for the toy prototypes varied between $ 3.70 and $ 13.58. The urban pruning wastes of the species studied have physical, chemical and mechanical attributes suitable for the manufacture of toys. This use has strong potential for environmental, economic and social sustainability and the toys are pedagogically accepted by adults and children.

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The primary sludge produced by the wastewater treatment plant of a pulp and paper mill has high physicochemical heterogeneity, which limits the efficiency of thermochemical methodologies for the final disposal of this residue. As a solution, co-pelletization of the Primary Sludge (PS) with two other principal Industrial Solid Residues (ISRs) of the plant, Coal Boiler Ashes (CBA) and Wood Waste chips (WW), was proposed as a way to valorize the PS for energy use, while reducing dewatering costs. The energy potential was evaluated through a series of thermal co-processing tests of disaggregated and pelletized mixtures. Due to their differing fixed-carbon-to-volatile-material ratios, combining the ISRs resulted in a reduction of up to 45% of the mass of the ISR generated, improving the disposal conditions and achieving a minimum thermal power of 5.0 MJ/Nm3 through gasification. Finally, the environmental implications of the thermal co-processing of the wastes were assessed, finding very low impacts due to pollutant emissions, in accordance with the legal environmental regulations in force in Colombia.

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Three kinds of waste resulting from woods from the Colombian industry were selected (PinusPátula, Tectona Grandis and Acacia Mangium) in order to assess their energy potential. Several techniques of physicochemical characterization were used to predict the most appropriate energy exploitation process in each case; which was validated at laboratory scale by carrying out the torrefaction, gasification and combustion process. Results allowed us to the identification of the high energy potential of such wood waste as well as their feasibility to generate torrefied products and synthesis gas as products with greater added values. As a special case, the species Tectona Grandis displayed the greatest conversion and synthesis gas quality on the basis of the gasification process, due to its physicochemical characteristics. These samples can be torrefacted in order to get a new product with higher energy potential than the original sample. Experimental study carried out, allowed us to demonstrate that there is a relationship between biomass chemical composition, yield, and process products. In addition, applying an additivity law of individual effects of the component, it is not possible to predict the process performances.

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It was the aim of this work to evaluate the adsorptive performance of the biochar obtained from the gasification of wood residues onto a solution of Indosol Black NF1200 dye. The study was performed by means of factorial design 22, having as control variables: pH and adsorbent's granulometry. Batch tests were carried out at 200 rpm for 3 h (T = 28 °C). As output variable, the percentage removal of dye was determined. The best operating conditions were pH = 2 and 100 mesh granulometry. Also, adsorbent dosage studies were carried out, as well as equilibrium and adsorption kinetics. Both kinetics and equilibrium of adsorption tests were proceeded in basic and acid medium. For a basic pH value (pH = 12), it was concluded the equilibrium was reached in about 3 h of experiment, the experimental qmax value was near 12 mg g-1, and the equilibrium data fitted the Langmuir model. On the other hand, for tests with pH = 2, the equilibrium was reached after 5 min of experiment, the experimental qmax value was over 185 mg g-1, and the equilibrium data fitted both the Langmuir and Freundlich models. Thus, the biochar produced via gasification of wood wastes appears to be a promising adsorbent for the removal of azo dyes from textile wastewater, especially when working at lower pH values. Also, for a 10-kg/h consumption of wood residue, approximately 10 kW of energy is generated and 1 kg of biochar is produced, which represents another advantage from the environmentally friendly point of view. Graphical abstract.

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A survey was carried out in the wood industries of Manaus, Amazonas, Brazil, where 20 furniture factories, eleven sawmills and six plywood mills were investigated, mainly to evaluate the use of wood preservatives, storage, drying and utilisation efficiency of raw material, including waste. Only four furniture factories used wood preservatives and all the plywood mills used the preservatives added to the resin-glue, thus restricting this product to the glue line. Log storage is in water and/or log yards, in which case, the logs arc piled up in direct contact with the ground. The majority of the industries do not use correct drying procedures, with artificial drying restricted to the plywood mills and two sawmills. Only two furniture factories used solar dryers. There is an enormous wastage of raw material and almost no use of residues, which arc normally used in power generation and pottery and bakery ovens.

Este trabalhoeresultante de uma pesquisa realizada cm indústrias madeireiras da cidade de Manaus, envolvendo 20 movelarias, onze serrarias e seis fábricas de compensados, onde foram focalizados, principalmente, o uso de produtos preservantes de madeira, estocagem, secagem da madeira e aproveitamento da matéria-prima. Desse universo, constatou-se que apenas 4 movelarias utilizam preservantes e que as seis fábricas de compensados usam este produto, misturando-o ao adesivo, restringindo o seu uso à linha dc cola. Constatou-se também que a estocagem das toras é feita dentro da água e/ou no pátio. Neste caso, são empilhadas umas sobre as outras c em contato direto com o solo. A maioria das indústrias não utiliza uma secagem adequada, sendo que a secagem artificial, a alta temperatura, é restrita às indústrias de compensado e à duas serrarias. No setor moveleiro apenas duas fábricas fazem uso do secador solar. Verificou-se também um desperdício muito grande da matéria prima, havendo pouco aproveitamento dos resíduos da madeira, que em geral são utilizados na geração de energia em caldeira e em fornos de olarias e padarias.

RESUMO

A survey was carried out in the wood industries of Manaus, Amazonas, Brazil, where 20 furniture factories, eleven sawmills and six plywood mills were investigated, mainly to evaluate the use of wood preservatives, storage, drying and utilisation efficiency of raw material, including waste. Only four furniture factories used wood preservatives and all the plywood mills used the preservatives added to the resin-glue, thus restricting this product to the glue line. Log storage is in water and/or log yards, in which case, the logs arc piled up in direct contact with the ground. The majority of the industries do not use correct drying procedures, with artificial drying restricted to the plywood mills and two sawmills. Only two furniture factories used solar dryers. There is an enormous wastage of raw material and almost no use of residues, which arc normally used in power generation and pottery and bakery ovens.

Este trabalhoeresultante de uma pesquisa realizada cm indústrias madeireiras da cidade de Manaus, envolvendo 20 movelarias, onze serrarias e seis fábricas de compensados, onde foram focalizados, principalmente, o uso de produtos preservantes de madeira, estocagem, secagem da madeira e aproveitamento da matéria-prima. Desse universo, constatou-se que apenas 4 movelarias utilizam preservantes e que as seis fábricas de compensados usam este produto, misturando-o ao adesivo, restringindo o seu uso à linha dc cola. Constatou-se também que a estocagem das toras é feita dentro da água e/ou no pátio. Neste caso, são empilhadas umas sobre as outras c em contato direto com o solo. A maioria das indústrias não utiliza uma secagem adequada, sendo que a secagem artificial, a alta temperatura, é restrita às indústrias de compensado e à duas serrarias. No setor moveleiro apenas duas fábricas fazem uso do secador solar. Verificou-se também um desperdício muito grande da matéria prima, havendo pouco aproveitamento dos resíduos da madeira, que em geral são utilizados na geração de energia em caldeira e em fornos de olarias e padarias.