scholarly journals Synthesis and characterization of biopolyols through biomass liquefaction of wood shavings and their application in the preparation of polyurethane wood composites

2021 ◽  
Author(s):  
Adam Olszewski ◽  
Paulina Kosmela ◽  
Łukasz Piszczyk
Keyword(s):  
Production Systems ◽  
Agricultural Waste ◽  
Hydraulic Press ◽  
Wood Composites ◽  
Step Method ◽  
Wood Processing ◽  
Wood Shavings ◽  
Significant Step ◽  
European Industry ◽  
Poly Ethylene

AbstractThe sustainability of production systems in wood processing, wood industry, and wooden waste disposal is an important issue for European industry and society. Proper development of products based on renewable wood resources gives an opportunity to provide materials with long-term environmental, social, and economic sustainability. This study aims to establish a new way of forestry and agricultural waste materials utilization by synthesis of bio-based polyols and manufacturing of polyurethane wood composites (PU-WC). The first part of this paper describes the liquefaction of wood shavings at a temperature of 150 °C for 6 h in three different solvents—glycerol, poly (ethylene glycol) and their mixture in a 1:1 ratio. The second part deals with the synthesis of polyurethane (PU) resins containing 90% of biopolyol. Eight sets of materials with different NCO:OH ratios were obtained in a one-step method using a hydraulic press. These materials were characterized, and the material with the most promising properties was selected for polyurethane wood composites production. Composites with 40%, 50%, 60%, and 70% of wood shavings were obtained. The addition of filler caused an increase in flexural strength, Young`s modulus, hardness, and impact strength. Scanning electron microscopy (SEM) showed good adhesion between the polymer and the filler. The optimum filler content is between 50 and 60% by weight of the composite. The presented study provides a significant step toward a greener alternative for materials produced mainly from non-renewable resources.

The influence of the addition of ground olive stone on the thermo-mechanical behavior of compressed earth blocks

2020 ◽  
Vol 108 (2) ◽  
pp. 203
Author(s):  
Samia Djadouf ◽  
Nasser Chelouah ◽  
Abdelkader Tahakourt
Keyword(s):  
Thermal Conductivity ◽  
Compressive Strength ◽  
Mechanical Behavior ◽  
Agricultural Waste ◽  
Hydraulic Press ◽  
Dry Density ◽  
Olive Stone ◽  
Compressed Earth Blocks ◽  
Clay Matrix ◽  
Earth Blocks

Sustainable development and environmental challenges incite to valorize local materials such as agricultural waste. In this context, a new ecological compressed earth blocks (CEBS) with addition of ground olive stone (GOS) was proposed. The GOS is added as partial clay replacement in different proportions. The main objective of this paper is to study the effect of GOS levels on the thermal properties and mechanical behavior of CEB. We proceeded to determining the optimal water content and equivalent wet density by compaction using a hydraulic press, at a pressure of 10 MPa. The maximum compressive strength is reached at 15% of the GOS. This percentage increases the mechanical properties by 19.66%, and decreases the thermal conductivity by 37.63%. These results are due to the optimal water responsible for the consolidation and compactness of the clay matrix. The substitution up to 30% of GOS shows a decrease of compressive strength and thermal conductivity by about 38.38% and 50.64% respectively. The decrease in dry density and thermal conductivity is related to the content of GOS, which is composed of organic and porous fibers. The GOS seems promising for improving the thermo-mechanical characteristics of CEB and which can also be used as reinforcement in CEBS.

scholarly journals Optimization of pretreating poplar wood shavings with cellulase to produce binderless fiberboard using response surface methodology

BioResources ◽  
2020 ◽  
Vol 15 (3) ◽  
pp. 6431-6441
Author(s):  
Jianguo Wu ◽  
Yuanyuan Wang ◽  
Zhao Zhang ◽  
Xuanxian Luo ◽  
Chi Wang ◽  
...  
Keyword(s):  
Response Surface Methodology ◽  
Response Surface ◽  
Bending Strength ◽  
Good Choice ◽  
P Value ◽  
Poplar Wood ◽  
Wood Processing ◽  
Wood Shavings ◽  
Validation Experiment ◽  
Pretreatment Conditions

Wood processing waste, poplar wood shavings, were used for fiberboard production, and the pretreatment conditions using cellulase were studied using response surface methodology (RSM). After single factors optimization, central level of temperature, dosage, and liquid/solid ratio (LSR) of cellulase pretreatment conditions were obtained. Further optimization to study the influence of the factors was carried out using Box-Behnken design of experiments. A second-order polynomial equation was obtained, and the low p-value (<0.007) implied that the model was highly significant by analysis of variance (ANOVA). The optimized cellulase pretreatment conditions for maximum bending strength (BS) of the fiberboard were determined by ridge analysis as 44.4 °C of temperature, 1.23 U/g of dosage, 4.2 of LSR, and 5 h of pretreatment time. Under the optimized conditions, the BS of the fiberboard reached 25.12 ± 0.35 MPa by validation experiment, which was twice that of the fiberboard without pretreatment. Thus, the cellulase pretreatment should be a good choice to produce high-strength binderless fiberboard.

scholarly journals WOOD COMPONENTS AS SOURCES OF PENTO-CONTAINING RAW MATERIALS FOR SYNTHESIS OF USEFUL COMPOUNDS, PRODUCTS AND REAGENTS

2021 ◽  
Vol 64 (3) ◽  
pp. 107-115
Author(s):  
Irina A. Chetvertneva ◽  
Oleg Kh. Karimov ◽  
Galina A. Teptereva ◽  
Natalia S. Tivas ◽  
Eldar M. Movsumzade ◽  
...  
Keyword(s):  
Raw Materials ◽  
Condensation Reaction ◽  
Agricultural Waste ◽  
Monomer Unit ◽  
Paper Industry ◽  
Raw Material ◽  
Chemical Transformations ◽  
Covalent Bonds ◽  
Industry Waste ◽  
Wood Processing

The paper considers the main components and products of wood processing, agricultural waste, pulp and paper industry waste and qualifies them as sources of pentose-containing resource-renewable domestic raw materials. The article describes in detail the structural components of wood as a natural polymer, which contains aromatic and carbohydrate parts. It is noted that these poly-mers are promising as raw materials for the production of useful chemical products. The role of lignin, cellolose and hemicellulose in the design of mechanical and structural properties of wood is considered. The article considers the features of the sulfonation reactions of the lignin monomer unit depending on the pH of the medium: acidic, neutral and alkaline. There are three main reac-tions that occur simultaneously with lignin in the process of wood delignification during sulfite cooking, such as the sulfonation reaction, the hydrolytic destruction reaction, and the condensation reaction. It is shown that the lignin-hemicellulose matrix contains three types of interconnected mesh structures: the lignin itself; a network of covalent bonds of lignin with hemicelluloses, and a network whose structure is obtained due to the hydrogen bond and the forces of the physical inter-action of lignin and hemicelluloses. The features of chemical transformations of the monomeric aromatic link of lignosulfonate – phenylpropane unit in the processes of wood delignification, the main chemical reactions of wood raw material delignification under the conditions of sulfite and neutral-sulfite brews are shown. The method of quantitative determination of monosaccharides in the composition of the carbohydrate part is proposed.

scholarly journals Exploiting Olive Mill Byproducts and Other Waste for Organic Weed Management

Horticulturae ◽  
2019 ◽  
Vol 5 (3) ◽  
pp. 59 ◽  
Author(s):  
Tubeileh ◽  
Schnorf ◽  
Mondragon ◽  
Gray
Keyword(s):  
Weed Management ◽  
Crop Production ◽  
Production Systems ◽  
Agricultural Waste ◽  
Petri Dish ◽  
Bell Pepper ◽  
Loam Soil ◽  
Vegetation Water ◽  
Organic Weed Management ◽  
Olive Mill

Weed management represents one of the most serious and costly challenges in organic crop production systems. Agricultural waste/byproducts might present phytotoxicity that can be exploited to control weeds. Two experiments were designed to study the effects of four concentrations of olive vegetation water (OVW) and a control water treatment (with no OVW) on cheeseweed (Malva parviflora L.) seed germination in petri dishes and pots. In a third experiment, two rates of four composts (crop residue mix (CR), olive pomace (OP), dairy/horse manure (DM), and an OP/DM mix) were mixed into a clay‒loam soil at 0.10 or 0.20 L L−1, to assess their effects on weed number and biomass, in addition to bell pepper (Capsicum annuum L.) growth. In the petri dish experiment, the three highest OVW concentrations completely prohibited germination during the five-week duration of the study. For the pot experiment, 25 mL application of OVW significantly delayed and reduced cheeseweed germination, with the reduction being proportional to the concentration of OVW. In the third experiment, composts reduced weed dry matter (composed mostly of purslane (Portulaca oleracea L.)), with the CR compost being the most effective, reducing total weed biomass by 67% compared to the control. CR10 and DM10 tended to increase bell pepper yields, although none of the plant parameters was significantly affected by the compost treatments.

Synthesis and sizing performances of water-soluble polyester based on bis(2-hydroxyethyl) terephthalate derived from depolymerized waste poly(ethylene terephthalate) fabrics

2018 ◽  
Vol 89 (4) ◽  
pp. 572-579 ◽  
Author(s):  
Jing Lu ◽  
Mengjuan Li ◽  
Yanyan Li ◽  
Xiaoqiang Li ◽  
Qiang Gao ◽  
...  
Keyword(s):  
Surface Tension ◽  
Fourier Transform ◽  
Ethylene Terephthalate ◽  
Water Soluble ◽  
Chemical Recycling ◽  
Step Method ◽  
Pet Fabric ◽  
Poly Ethylene Terephthalate ◽  
Poly Ethylene ◽  
Viscosity Stability

This work aimed at effective chemical recycling of waste poly(ethylene terephthalate) (PET) fabrics into water-soluble polyester (WSP). For this, PET fabric waste was depolymerized using excess ethylene glycol (EG) in the presence of zinc acetate as catalyst. The glycolysis product of PET, bis(2-hydroxyethyl) terephthalate (BHET) was then used to synthesize WSP by a three-step method, that is, transesterification, esterification and polycondensation. The structures of BHET and WSP were identified by Fourier transform infrared spectra. Sizing performances of WSP were studied, and it was found that the surface tension of WSP size (57 mN/m, 22℃, 0.5% of weight) was lower than common sizes, the viscosity of WSP size was 1–2 mPa·S (95℃, 6% of weight) and the viscosity stability was larger than 90% at this temperature. The mixture of WSP and starch showed stronger adhesion to polyester–cotton roving and polyester roving than onefold starch. K/ S values of fibers before sizing and after desizing showed a slightly difference, which indicated that WSP would not influence the color of yarns when used as the sizing agent.

scholarly journals Forecasting of the processing time as the base of simulation of the production system behavior in real conditions

2005 ◽  
pp. 7-13
Author(s):  
Milan Vukicevic
Keyword(s):  
Production System ◽  
Processing Time ◽  
Production Systems ◽  
Direct Costs ◽  
Present Moment ◽  
System Behavior ◽  
Special Significance ◽  
Modern Approach ◽  
Precise Information ◽  
Wood Processing

The absence of precise information on the magnitudes that determine the behavior of the production system generates the disturbances of the system. The consequence is the low efficacy of the system and the high costs. Therefore, it is necessary to create the base for the prediction of individual magnitudes and thus enable the simulation of the production system behavior in real conditions. The information on time norms has a special significance. It is the base of planning the terms and of defining a part of direct costs. Modern approach in the identification of standard times should be established on new foundations. It should appreciate the specificities of the present moment, as well as the future tendencies in wood processing. They are the production system dynamistic, conditioned predominantly by discontinuous production, as well as by the necessity of cooperation of the production systems. In this study, the approach to the identification of standard times is original, supporting the modern tendencies in wood processing and it has an applicative character.

scholarly journals Preparation of a mimetic and degradable poly(ethylene glycol) by a non-eutectic mixture of organocatalysts (NEMO) via a one-pot two-step process

RSC Advances ◽  
2019 ◽  
Vol 9 (68) ◽  
pp. 40013-40016 ◽  
Author(s):  
S. Moins ◽  
P. Loyer ◽  
J. Odent ◽  
O. Coulembier
Keyword(s):  
Ethylene Glycol ◽  
Eutectic Mixture ◽  
Poly Ethylene Glycol ◽  
Step Method ◽  
One Pot ◽  
Step Process ◽  
Poly Ethylene

A one-pot, two-step method for the preparation of degradable PEG is here presented.

scholarly journals The Typical Farm Approach and Its Application by the Agri Benchmark Network

Agriculture ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 646
Author(s):  
Craig Chibanda ◽  
Katrin Agethen ◽  
Claus Deblitz ◽  
Yelto Zimmer ◽  
Mohamad. I. Almadani ◽  
...  
Keyword(s):  
Agricultural Production ◽  
Production Systems ◽  
Standard Operating Procedure ◽  
Practice Change ◽  
Step Method ◽  
Change Analysis ◽  
Non Profit ◽  
Institutional Settings ◽  
The Status ◽  
Global Agriculture

Global agricultural production is dynamic and complex as various factors impact it. Understanding global agricultural production systems and farmers’ decisions requires an internationally standardized and scientifically sound approach. The agribenchmark Network is a global, non-profit network of producers and agricultural experts which aims to analyze and understand the key drivers of current and future trends and developments in global agriculture. The Network combines its in-depth knowledge of production systems with its expertise in analyzing international commodity markets and value chains to provide scientifically sound advice to policymakers, producers and agribusinesses. This paper details the agribenchmark Standard Operating Procedure (SOP), which is the step-by-step method of establishing typical farm information and quantifying their data. The paper also illustrates how the typical farm approach is applied by the agribenchmark Network to analyze and understand global agriculture, production systems and adaptation strategies. The paper provides examples of how the Network applies the approach in analyzing the status-quo of production systems, benchmarking, practice change analysis and policy analysis. The paper concludes that although the typical farm approach and the institutional settings (agri benchmark) present some limitations, the approach and the Network provide comprehensive, consistent and coherent data on farm economics.

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