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•Effect of heating sources on oil yield from waste pyrolysis is studied by big data.•Machine learning regression model is developed to predict oil yield.•Microwave heating is the most ...efficient method among the 4 heating sources.•Order of importance of key pyrolysis parameters affecting oil yield is provided.•Heating source and heating rate should be optimized to achieve max oil yield.
This work emphases the influence of using different heating sources (direct thermal, solar, infrared, microwave heating) on the pyro-oil yield. The effect of the dominating process parameters, namely the heating rate and final temperature, are thoroughly discussed with respect to the heating and reaction mechanism involved. Emphasis is then placed on reviewing the application of microwave (MW) heating in pyrolysis as a relatively new technology with many promising features, particularly the little-known mechanisms of MW heating, new MW heating pattern and pathway using MW absorbents for pyrolysis of waste materials. Machine learning (ML) techniques were then used to statistically analyze the 182 observations in 59 pyrolysis cases obtained from previous pyrolysis practices. The ML linear regression model was developed to predict oil yield by five input variables (feedstock type, feedstock size, heating rate, final temperature, and heating source), which can be used as a guideline for pyrolysis production management. By comparing three heating sources (direct, solar and MW), MW heating is found to be the most efficient method to achieve the highest oil yield. The Decision Tree Analysis demonstrates that the importance order for key variables is as: Log feedstock size > Log heating rate > Heating rate > Temperature > Feedstock size > Heating sources > Feedstock type. Future work should focus on optimizing the heating method and heating rate to achieve optimal yield and quality of pyro-oil. The findings are envisaged to be useful for scaling up the pyrolysis of waste materials for industrial energy applications.
Recent studies on the exploration of eco-friendly approach by utilizing large-scale waste materials as potential catalyst in biodiesel production have attracted much attention. The development of ...heterogeneous catalysts especially from calcium has gained much awareness due to the large availability of calcium-rich waste materials and their corresponding high catalytic activity in the transesterification of oil. Most of the waste materials employed as heterogeneous catalysts have an abundance of natural Ca content and they have high catalyst activity and selectivity despite being environment-friendly and cost-effective. Heterogeneous catalysts with high activity can be produced from Ca based waste materials when calcined at high temperatures. This review gives a brief overview of the developments of various Ca based catalysts derived from waste materials as an efficient catalyst for biodiesel production with significant yield. Industrial wastes (red mud, slag, ash) and biological catalysts (chicken eggshells, mollusk shells, animal bones) possess enormous potential towards developing an economical catalyst and subsequently, low-cost biodiesel generation. However, future challenges await a better utilization of useless wastes into a useful resource to satisfy human needs.
•Calcination temperature above 700 °C is vital for high surface area catalyst.•Chicken eggshell is an efficient catalyst for Jatropha and Karanja oil conversion.•Calcined animal bones transform into HAP as highly active support for catalyst.•Waste fish scale derived catalyst is a low cost catalyst with excellent reusability.•THF as co-solvent in methanol accelerates the reaction kinetics.
Modification of asphalt pavement materials by using recycled waste tires in form of crumb rubber (CRM) is getting significant importance for saving resources as well as protecting ecosystem. So, in ...this study the crumb rubber size and percentage content effect on the performance properties of binder and mixtures were evaluated. A detailed experimental program has been performed using design expert software considering the variables like rubber size and content and their responses which were viscosity, Indirect Tensile strength (ITS), Tensile strength ratio (TSR) durability and Resilient Modulus (Mr). The viscosity of control binder with the addition of crumb rubber at high temperatures showed good improvement. The performance properties viz., ITS, TSR and Mr showed similar behavior as the size and content of crumb rubber increased under different loading conditions. The statistical models prepared using the analysis tool were found significant and well fitted based on high R2 (>0.80), high adequate precision value (>4), insignificant lack of fit and low p-value. Analysis of variance (ANOVA) model theoretical results generated by the response surface methodology (RSM) analysis were further validated by the experiments with <5 % of error showing good agreement between theoretical and experimental results. Study results showed that modified binder with 10 % crumb rubber passing sieve No. 40 in mixtures showed good improvement of mechanical properties indicating the potential source of recycled waste material usage in the pavement construction.
•Recycled waste tires for saving natural resources and protecting ecosystem.•The effect of crumb rubber content showed improvement in the binder performance.•A detailed experimental program using design expert software.•Crumb rubber inclusion in HMA indicated good mechanical performance.
The implementation of a building construction project is unavoidable from the emergence of waste material. Construction material waste is defined as something that is over what is required. This ...study intends to find the application of construction waste management in building construction projects to minimize the waste material. Data was collected using observation, interviews, and distributing questionnaires to 4 building project parties in Central Java using a random sampling method. Data analysis was carried out by descriptive analysis to determine the type and cause of the highest waste material and supported by regression and correlation analysis to assess the application of ways to minimize waste material. The results of data analysis show that the most types of waste material are formwork wood, reinforcing steel, concrete, and cement. The factor causing waste material that most often occurs is the design change factor that comes from the design phase. Based on the analysis, the effort to minimize waste material that is the most influential on it is improving the quality of tool and material management by providing training to construction personnel related to materials construction used
Grass waste was used for transform an inexpensive waste into health. Silver nanoparticles (AgNPs) have been synthesized using waste material (dried grass). The average size of silver nanoparticles ...observed in transmission electron images was estimated to be about 15 nm. The anticancer, antifungal and antibacterial effect of AgNPs were studied in vitro. The minimum inhibitory concentration of AgNPs against Pseudomonas aeruginosa and Acinetobacter baumannii was calculated about 3 µg/ml. The highest level of inhibitory effect of AgNPs against Fusarium solani was close to 90% at a concentration of 20 μg/ml of AgNPs. An inhibitory effect on the cancer cell growth is reach, by increasing the concentration of AgNPs to 5 µg/ml; the cancer cells' survival decreases about 30%. Western results showed that the expression of Cyclin D1 protein of MCF-7 cell line decreased after treatment with the effective concentration of AgNPs.
•We have provided information regarding bitumen and its adverse impact to the human life and environment.•We present the prospect of alternative binders that can be used to reduce the use of ...bitumen.•We have proved that, use of bio oil, polymer and waste cooking oil can be an effective alternative by literature review.•We provide instructions about the criteria and experimental method to do further study for future research.
Bitumen (asphalt) is viscoelastic, rheological and non-magnetic material composed of heavy hydrocarbons with low dielectric constant (ε′). It is a by-product of petroleum oil refinery. Though it is used as a binder for flexible pavement all over the world, it has severe environmental impacts. Bitumen is non-hazardous at room temperature but when heated at 165–200°C, it becomes toxic. Consequences, such as environmental degradation, depleting petroleum reserves and price-spiking, led researchers to explore alternative sources of obtaining binder for pavement. This paper provides an overview of the probable materials that could be used as an alternative binder. The materials obtained from bio-based sources, such as bio-oil, polymer, plastic, rubber and waste cooking oil and retrieved from waste material show promise and discussed. Further research is needed to make them satisfactory replacement of bitumen on an industrial scale, and be a sustainable source of binder for flexible pavement.
•Comprehensive review on integrating waste materials in pre-foamed concrete.•Utilization of different types of waste as cement and aggregate substitute.•Effect of various types of waste materials on ...properties of foamed concrete.•Foamed concrete is a promising avenue to incorporate waste materials for sustainability.
Several million tons of different types of wastes are generated every year globally and this is expected to increase in the future. Most of these wastes are dumped via landfilling or incineration which creates environmental concerns. One of the possible methods of utilizing these wastes is by incorporating them as alternatives to common concrete constituents. In this regard, foamed concrete could provide an excellent medium for incorporating these wastes in a large volume primarily due to low strength requirement of foamed concrete. A significant number of research is carried out to explore the idea of integrating waste materials in pre-foamed concrete. However, the limited knowledge available to recognize the utilization of these waste and the influence on foamed concrete limits the adoption of the concept and further development. Hence, this paper compiles and reviews the usage of various types of wastes such as industrial, agricultural, quarry, and construction industry wastes as a potential replacement for cement and fine aggregate in foamed concrete. Due to the unique composition and the resulting chemical and physical properties, as well as the nature of replacement (either as cement or fine aggregate replacement), each type of waste contributes differently to the performance of foamed concrete. Generally, a non-load bearing foamed concrete with low thermal conductivity, low density, and adequate compressive strength can be produced by incorporating the waste materials. This paper also describes the advantages of incorporating waste materials in foamed concrete compared to conventional concrete and proposes the further development of the concept for future application of a more sustainable and eco-friendly foamed concrete.
•Hydrogen serves as an alternative fuel with the potential to replace fossil fuels.•Thermo-catalytic plastic waste conversion to hydrogen offers a promising solution.•Plasma-assisted gasification ...outperforms the rest of the thermo-catalytic routes.•Pyrolysis, pyrolysis-air gasification, pyrolysis-steam reforming were discussed.•Pyrolysis- (CO2) dry reforming and pyrolysis-plasma catalysis methods were elaborate.
Hydrogen is an energy carrier that can be utilized in various applications, including power plants, the synthesis of high-value products, and clean transportation fuels without emissions. Hence, hydrogen is a potential candidate that can replace fossil fuels and reduce environmental pollution. The high demand for plastics is driving the plastics production rate to increase yearly, leading to a great accumulation of plastic waste materials resulting in a severe burden on the environment. Thermo-catalytic conversion of plastic waste materials to hydrogen and other high-value fuels is a promising route that can efficiently provide an ideal long-term solution necessary to overcome this environmental challenge. Developing durable and high-efficiency catalysts that can immerge hydrogen production from plastic wastes on the industrial scale is still a potential challenge for researchers. This study comprehensively summarizes and discusses the recently published literature for hydrogen production from plastic waste materials using different thermo-catalytic processes, including pyrolysis, pyrolysis-air gasification, pyrolysis-steam reforming, pyrolysis- (CO2) dry reforming, and pyrolysis-plasma catalysis. The scope of this review is to focus on the influence of catalysts and supports, catalysts synthesis method on the production yield of hydrogen, and the impact of several crucial reaction parameters like pyrolysis temperature, catalytic temperature, a catalyst to plastic, and steam to plastic ratios is inclusive in this review as well. The conclusions of this review study will be extremely valuable for researchers interested in the sustainable generation of H2 from plastic waste materials.
Pectin is one of the finest natural polymer which has drawn great attention because of its applications in different fields. Due to the quintessential structure of pectin, it can be transformed into ...variety of useful products. It can be utilized as a blend in many polymers to make a mixture or a composite material. Owing to considerable collection in chemical conformation and cross-linking mechanism, different pectin based hydrogels have been prepared for different characteristics in pharmaceutical and bio-medical sites. Inventive properties of hydrogels like volubility, swellability, solvability and hydrophilicity make them better alternative for wastewater treatment. Recently, pectin based hydrogels have demonstrated excellent performance to eliminate various metal ions and dyes from the polluted water. The adsorption characteristics of pectin based hydrogels can be upgraded by using nanoparticles, which prompts to the development of hydrogel nano-composites. In this review article, we have summarized a comprehensive assessment in the direction of using pectin based hydrogels to remove toxic pollutants from aqueous solution. Sodium acrylate-co-N-isopropylacrylamide based pectin hydrogel has demonstrated the maximum adsorption capacities of 265.49, 137.43, 54.86, 53.86, 51.72 and 50.01 mg g−1 for the adsorption of methyl violet, methylene blue, Pb(II), Cu(II), Co(II) and Zn(II) respectively. We have also discussed the pectin structure, properties and applications in this article.
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•Hydrogel is used as sustainable noble material.•Structure and properties of pectin are described.•Pectin is produced from bio-waste materials.•Pectin based hydrogels are used in water purification.•The mechanical strength of pectin based hydrogel can be improved by incorporation of nanoparticles.
Waste in millions of tons is produced in the world each year and most of it is not recyclable. Furthermore, recycling waste consumes energy and produces pollution. In addition, the accumulation of ...waste in suburbs and disposal of waste is dangerous for the environment. Using waste material in concrete production is an appropriate method for achieving two goals i.e. eliminating waste and adding positive properties in concrete. Since the green concrete industry is expanding, it is necessary to evaluate concrete that contains waste from all aspects to determine its capability. This research consists of analyzing the use of waste as a partial substitute for sand. Leading waste material that has been used as substitutes is highlighted and the characteristic of the resulting concrete is evaluated in this research. Among other findings, rubber was found to have improved fire resistance and ductility in concrete, and agricultural and Polyethylene terephthalate (PET) wastes were successfully used in non-structural concrete, while glass helped to improve thermal stability. In this research aggregate and sand is replaced by waste materials of Polyvinyl Chloride (PVC) and Glass to check their effect on the mechanical properties. Lab tests were performed to analyze the flexural behavior of concrete samples having waste material. The results show how partial replacement of sand affects the behavior of concrete and based on that specify the conditions where it can be used. The results show that Young’s modulus, maximum bending stress, and bending deflection varies with the percentage composition of PVC and glass. Bedding stress and bending deflection decrease with PVC and glass composition up to 35%. Although Young’s modulus is fluctuating bending deflection will decrease.
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