Ying Ji^*, Xi Liu^*

Journal of Renewable Materials, Vol., , DOI:10.32604/jrm.2023.028439

Abstract The problem of low disposal and utilization rate of bulk industrial solid waste needs to be solved. In this paper, a high-activity admixture composed of steel slag-phosphate slag-limestone powder was proposed for most of the solid waste with low activity and a negative impact on concrete workability, combining the characteristics of each solid waste. The paper demonstrates the feasibility and explains the principle of the composite system in terms of water requirement of standard consistency, setting time, workability, and mechanical properties, combined with the composition of the phases, hydration temperature, and microscopic morphology. The results showed that the steel slag:phosphate… More >

Guiwu Lin, Kaige Liu, Yuliang Chen^*, Yunpeng Ji, Rui Jiang

Journal of Renewable Materials, Vol., , DOI:10.32604/jrm.2023.028290

Abstract This paper presents an experimental study to explore the compressive properties of fiber recycled aggregate concrete. A total of 75 specimens with the replacement rate of recycled coarse aggregate and fiber type were conducted under a uniaxial compressive test. The failure modes, stress-strain whole curves, peak stress, peak strain, and energy dissipation capacity were systematically observed and revealed. Test results indicate that steel fiber has the best modification effect on energy dissipation capacity and the toughness index of recycled concrete, corresponding to the enhancement of 81.75% and 22.90% on average. The addition of polyvinyl alcohol fiber can effectively improve the… More >

Yueqiang Yu^1,3, Minzheng Jiang^1,*, Sheng Gao^1,*, Ting Jiang¹, Bakary S. Doumbia², Bo Yan¹, Tingang Ma¹, Kexin Ren¹, Yinsong Liu¹

Journal of Renewable Materials, Vol., , DOI:10.32604/jrm.2023.030725

Abstract High-quality wood products and valuable wood crafts receive everyone’s favor with the rapid development of the economy. In order to improve the cutting surface quality of wood forming parts, the cutting experiment of renewable Fraxinus mandshurica was conducted by waterjet-assisted CO₂ laser (WACL) technology. A quadratic mathematical model for describing the relationship between surface roughness changes and cutting parameters was established. The effects of cutting speed, flow pressure and laser power on the kerf surface roughness of Fraxinus mandshurica when cutting transversally were discussed by response surface method. The experimental results showed that kerf surface roughness decreased under a lower… More >

Zhimei Li¹, Kuan Tian², Keping Wang², Zhengyi Li², Haoli Qin^1,*, Hu Li^2,*

Journal of Renewable Materials, Vol., , DOI:10.32604/jrm.2023.030122

Abstract Sustainable acquisition of bioactive compounds from biomass-based platform molecules is a green alternative for existing CO₂-emitting fossil-fuel technologies. Herein, a core–shell magnetic biocarbon catalyst functionalized with sulfonic acid (Fe₃O₄@SiO₂@chitosan-SO₃H, MBC-SO₃H) was prepared to be efficient for the synthesis of various N-substituted pyrroles (up to 99% yield) from bio-based hexanedione and amines under mild conditions. The abundance of Brønsted acid sites in the MBC-SO₃H ensured smooth condensation of 2,5-hexanedione with a variety of amines to produce N-substituted pyrroles. The reaction was illustrated to follow the conventional PallKnorr coupling pathway, which includes three cascade reaction steps: amination, loop closure and dehydration. The… More >

John Freddy Gelves-Díaz^1,*, Ludovic Dorkis², Richard Monroy-Sepúlveda¹, Sandra Rozo-Rincón¹, Yebrail Alexis Romero-Arcos¹

Journal of Renewable Materials, Vol., , DOI:10.32604/jrm.2023.029270

Abstract Secondary lignocellulosic biomass has proved to be useful as an energy source through its oxidation by means of combustion processes. In accordance with the above, in this paper, we wanted to study the ash from urban pruning residues that are generated in cities in the Neotropics. Species such as Licania tomentosa, Azadirachta indica, Ficus benjamina, Terminalia catappa, Leucaena leucocephala, Prosopis juliflora and Pithecellobium dulce were selected because they have been previously studied and showed potential for thermal energy generation. These materials were calcined in an oxidizing atmosphere and characterized by X-ray diffraction and fluorescence, scanning electron microscopy with microchemistry, BET… More >

Yifan Liu¹, Shufeng Ma², Feijie Wang¹, Liqiang Wang^1,*

Journal of Renewable Materials, Vol., , DOI:10.32604/jrm.2023.028251

Abstract The molded pulp, a product of three-dimensional papermaking technology, is environmentally friendly and has a low environmental impact due to its ability to decompose quickly in the natural environment after disposal. The application of molded pulp for food packaging can replace or reduce the use of plastic food packaging. Researchers extract fibers from plants for the production of safe and hygienic molded pulp for food packaging, and they also study and enhance the qualities of molded pulp to broaden its use in the food industry. This paper reviews the sources and varieties of plant fiber used in molded pulp for… More >

Ting Qu, Bo Wang, Hequn Min^*

Journal of Renewable Materials, Vol., , DOI:10.32604/jrm.2023.027136

Abstract With the growing global environmental awareness, the development of renewable and green materials has gained increased worldwide interest to substitute conventional materials and are favorable for sustainable economic development. This paper proposed a novel eco-friendly sound absorbing structure (NSAS) liner for noise reduction in elevator shafts. The base layer integrated with the shaft walls is a damping gypsum mortarboard, and a rock wool board and a perforated cement mortarboard are used to compose the NSAS. Based on the acoustic impedance theory of porous materials and perforated panels, the sound absorption theory of the NSAS was proposed; the parameter effects of… More >

Elham Azadeh¹, Ummi Hani Abdullah^2,3, Christine Gerardin^1,*, Antonio Pizzi^1,*, Philippe Gerardin¹, Cesar Segovia⁴

Journal of Renewable Materials, Vol., , DOI:10.32604/jrm.2023.030373

Abstract Water repellant, flexible biofoams using tannin esterified with various fatty acid chains, namely lauric, palmitic and oleic acids, by reaction with lauryl chloride, palmitoyl chloride, and oleyl chloride were developed and their characteristics compared with the equivalently esterified rigid biofoams. Glycerol, while initially added to control the reaction temperature, was used as a plasticizer yielding flexible biofoams presenting the same water repellant character that the equivalent rigid foams. Acetaldehyde was used as the cross-linking agent instead of formaldehyde, as it showed a better performance with the esterified tannin. The compression results showed a significant decrease of the Modulus of Elasticity… More >

Qianyu Zhang^1,2,#, Shi Chen^1,2,#, Long Cao^1,2, Hong Lei³, Antonio Pizzi⁴, Xuedong Xi^1,2,*, Guanben Du^1,2

Journal of Renewable Materials, Vol., , DOI:10.32604/jrm.2023.029537

Abstract Using non-toxic, low-volatile glyoxal to completely replace formaldehyde for preparing urea-glyoxal (UG) resin adhesive is a hot research topic that could be of great interest for the wood industry. However, urea-glyoxal (UG) resins prepared by just using glyoxal instead of formaldehyde usually yields a lower degree of polymerization. This results in a poorer bonding performance and water resistance of UG resins. A good solution is to pre-react urea to preform polyurea molecules presenting already a certain degree of polymerization, and then to condense these with glyoxal to obtain a novel UG resin. Therefore, in this present work, the urea was… More > Graphic Abstract

Antonio Pizzi^*

Journal of Renewable Materials, Vol., , DOI:10.32604/jrm.2023.030930

Abstract This brief article reviews a very particular and quite narrow field, namely what has been done and what is needed to know for tannin adhesives for wood panels to succeed industrially. The present fashionable focus on bioadhesives has led to producing chemical adhesive formulations and approaches for tannin adhesives as a subject of academic publications. These, as good and original they might be, are and will still remain a rather empty academic exercise if not put to the test of real industrial trials and industrial use. They will remain so without the “little” secrets and techniques outlined here that show… More >