Environment-friendly Applications Research Articles

Surface engineering of the lightweight aggregates derived from the dredged harbor sediment for green fertilizer utilization

Pursuing the circular economy driving scientists to explore additional environmental friendly application of lightweight aggregates (LWAs) derived from the dredged harbor sediment. We herein demonstrated the surface engineering of LWAs for the green fertilizer application by hydrothermally depositing iron species (Fe@LWAs) to increase the chemical reactivity. The obtained Fe@LWAs were first applied to adsorb nutrients (NH4+ and PO43−). Desorption of the adsorbed nutrients was then utilized as the replacement of commercial chemical fertilizer to cultivate mung bean sprouts to further biofix environmental CO2. Experimental results showed that the deposited iron species was the dominant component regulating the chemical behaviors of Fe@LWAs and adsorbed PO43− played an important role for Fe@LWAs to adsorb NH4+. With the coexistence of NH4+ and PO43−, the adsorption capacities of Fe@LWAs were 0.220 mg-NH4+/g and 0.486 mg-PO43−/g. The growth rate of mung bean sprouts using nutrient loaded Fe@LWAs was similar to those cultivated using commercial chemical fertilizer. Despite the nutrient recovery and mung bean cultivation decreasing the carbon footprint of the Fe@LWAs, the preparation of LWAs by high temperature sintering and the following hydrothermal surface modification consumed intensive energy. Consequently, the green fertilizer application of Fe@LWAs requires at least 594 cycles of nutrient recovery and mung bean cultivation to reach negative carbon emissions. Importantly, the cultivated mung bean sprouts could return to the soil to effectively secure the biofixed CO2, which could contribute additional environmental implications by increasing the organic content in the soil at the same time.

Thermo-Mechanical, Structural, and Biodegradability Properties of Water Hyacinth and Sheep Wool Fiber Reinforced Hybrid Polypropylene Composites

Hybrid fiber reinforcements can incorporate a wider array of qualities than single fiber reinforcement. Instead of synthetic fibers, applying plant and animal-based organic materials as reinforcement in polymer matrix offers certain benefits, such as low price, greater availability, and better biodegradability. In the present study, water hyacinth fiber and sheep wool fiber reinforced polypropylene hybrid composites were fabricated at three different (5, 10, and 15 wt.%) fiber loading. The effect of fiber loading on thermo-mechanical, structural, and biodegradability properties was subsequently investigated. The manufacturing process of the composite material was carried out with utmost consideration for biodegradability, since polypropylene, the primary constituent, is not inherently biodegradable. The insertion of fibers into the polypropylene matrix showed variance in properties of different aspects. The tensile strength of the composites displayed a downward trajectory (from 25 to 10 MPa) with a 15% increase in fiber loading due to voids, and fiber dispersion, while impact strength exhibited an opposite trend (from 25 to 32 J/m). Except for hardness, all the mechanical properties degraded slightly after the employment of the reinforcement. Fourier transform infrared spectroscopic analysis revealed the movement of typical peaks and the appearance of new peaks demonstrating the bonding between the fiber and the matrix. Thermogravimetric analysis showed that the thermal degradation temperature of the composites improved at maximum fiber loading. On the other hand, the goal of achieving biodegradability has been succeeded by the implementation of a combination of plant and animal-based fibers as biodegradability of the manufactured composites thrives with increasing fiber content for the presence of cellulosic bonds, as evident from the FTIR spectrum. Even though some properties of the hybrid composite declined slightly with increasing fiber loading, the other characteristics, including service temperature and biodegradability experienced a prospective advancement. Hence, the 15% fiber-loaded composite was found to be a potential candidate in terms of slightly high temperature and environment-friendly applications.

Synthesis, Characterization and Eco-friendly Applications of Biodegradable Polycaprolactone-Tapioca Starch Polymeric Composite Membrane

In the pursuit of sustainable materials, this study on the synthesis and multifaceted characterization of a novel biodegradable polymeric composite membrane. The polymeric composite composed of polycaprolactone (PCL) and tapioca starch (TS) was meticulously prepared and it’s properties were systematically investigated. FTIR was employed to elucidate the structure of the composite, while SEM facilitated the morphological examination. The biodegradability of the material was rigorously assessed through a burial method and a comparative analysis was also conducted against a commercially available facemask. The antimicrobial efficacy and the material’s suitability for water purification were also evaluated. The versatile application potential of the polymeric composite was further demonstrated through packaging tests utilizing tomatoes. The comprehensive investigated presented in this study demonstrates the advantageous sustain-ability of the PCL-TS polymer composite, hence highlighting its potential for many environmental friendly applications.

Genome sequence analysis and characterization of Bacillus altitudinis B12, a polylactic acid- and keratin-degrading bacterium.

Keratin-rich wastes, mainly in the form of feathers, are recalcitrant residues generated in high amounts as by-products in chicken farms and food industry. Polylactic acid (PLA) is the second most common biodegradable polymer found in commercial plastics, which is not easily degraded by microbial activity. This work reports the 3.8-Mb genome of Bacillus altitudinis B12, a highly efficient PLA- and keratin-degrading bacterium, with potential for environmental friendly biotechnological applications in the feed, fertilizer, detergent, leather, and pharmaceutical industries. The whole genome sequence of B. altitudinis B12 revealed that this strain (which had been previously misclassified as Bacillus pumilus B12) is closely related to the B. altitudinis strains ER5, W3, and GR-8. A total of 4056 coding sequences were annotated using the RAST server, of which 2484 are core genes of the pan genome of B. altitudinis and 171 are unique to this strain. According to the sequence analysis, B. pumilus B12 has a predicted secretome of 353 proteins, among which a keratinase and a PLA depolymerase were identified by sequence analysis. The presence of these two enzymes could explain the characterized PLA and keratin biodegradation capability of the strain.

Valorization of greek – Naxos emery in environmental friendly applications

The purpose of this study is to investigate the chemical composition of Greek Naxos emery, and reuse of Naxos emery in the light of new environmental applications discovered. Its chemical composition will help us to propose alternative ways of exploiting and using it. Emery was characterized by Scanning Electron Microscopy (SEM), Energy Dispersive X-ray spectroscopy (EDS) and X-Ray diffraction (XRD) and it was revealed that Greek emery elemental analysis showed that it consists of Oxygen, Aluminum, Silica, Carbon, Calcium and less Antimonium and Iron. Antimonium is the key element for Greek – Naxos emery. The three main components are Quartz, Diasporite and Hematite. By reusing emery through new innovative environmental applications, we can achieve sustainable management and environmental integration.

Biopesticides as Eco-friendly Substitutes to Synthetic Pesticides: An Insight of Present Status and Future Prospects with Improved Bio-effectiveness, Self-lives, and Climate Resilience

Synthetic pesticides are well-known not just for their efficiency in pest control, but also for their adverse effects on humans, ecology, and living biome's ecological relationships. Biopesticides are biodegradable, environment-friendly, and non-destructive insecticides that are safe for creatures. They leave no harmful residues in food or feed. Botanical, microbiological, and biochemical biopesticides are the three types of biopesticides. 3,000 tons of biopesticides are produced every year, accounting for around 2.5% of the overall pesticide market. Biopesticides are currently accessible in a variety of forms, including dust, granules, powders, emulsions, suspension concentrates, and so on. The Central Insecticide Board and Registration Committee (CIBRC) in India requires data on chemistry, bioefficacy, toxicity, packaging, and labeling to register biopesticides. Although India has registered 970 biopesticide products, lesser effectiveness, shorter shelf-life, lack of knowledge, and lengthy registration process remain hurdles. New and improved formulation methods might improve biopesticide efficacies, self-lives, and climate resiliency while lowering prices and making them economically competitive with synthetic chemicals. The main types of biopesticides, their benefits and downsides, worldwide and Indian market scenarios, formulations, registration procedures, and current advancements for users and environment-friendly applications and sustainable agriculture are all covered in this review article.

Investigation of impact strength at different infill rates biodegradable PLA constituent through fused deposition modeling

Polylactic Acid (PLA) is a natural source of corn, cassava, and sugarcane which is an economically produced renewable, biodegradable, compostable, and bio plastic resource of this world. It plays an important role in automobile, aerospace, and consumer applications. Moreover, the PLA was in research and development with high expectations for the industrial consumer, moving towards the development of a sustainable vehicle and the goal is greatly contributed to environmental friendly applications such as in two-wheeler and four-wheeler vehicles. The present investigation consists of different infill rates (50%, 75% & 100%). PLA was performed for two-wheeler mudguard material for improving the property through additive manufacturing (AM) followed by fused deposition modeling (FDM). Based on the literature survey, it was found that FDM printed PLA’s impact strength was lower than that fabricated through the Injection molding (IM) process due to improper selection of printing process parameters. In order to overcome this drawback were taken into account and to make a good environmentally friendly and biodegradable material was chosen as PLA. Finally, it was observed that the FDM-based PLA deposition has higher impact strength than IM because of introducing the printed sample of On-edge orientation and 100% infill rate. The finite element analysis (FEA) was performed to assess the impact strength of PLA at different infill rates by using the ANSYS software 17.2. The simulation results were compared with the experimental results, it was found that almost close to each other.

Assessment of some characteristics, properties of a novel waterborne acrylic coating incorporated TiO2 nanoparticles modified with silane coupling agent and Ag/Zn zeolite

Effect of rutile TiO2 nanoparticles modified with 3-(trimethoxysilyl) propyl methacrylate silane - TMSPM (m-TiO2) and Ag/Zn zeolite on the properties, and durability of acrylic waterborne coatings was studied. The obtained results indicated that m-TiO2 nanoparticles and Ag/Zn zeolite could disperse regularly in the acrylic polymer matrix. Consequently, the acrylic coating's abrasion resistance was improved in the presence of m-TiO2 or/and Ag/Zn zeolite. The acrylic coating's abrasion resistance depended on the content of m-TiO2 nanoparticles as well as the initial TMSPM content for modification of rutile TiO2 nanoparticles. The abrasion resistance of the m-TiO2 nanocomposite coating was higher than that of the unmodified TiO2 nanocomposite coating. The acrylic coating filled by 2 wt% TiO2 modified with 3 wt% TMSPM had the highest abrasion resistance value, leveling off at 187.2 L/mil. The abrasion resistance of acrylic coating filled by m-TiO2 reduced with increasing too high m-TiO2 nanoparticles content and using initial TMSPM content in high level for TiO2 modification. The starting temperature of weight loss of acrylic coating filled by m-TiO2 was lower than that of the neat acrylic coating. In comparison with the m-TiO2 nanoparticles, the Ag/Zn zeolite particles showed a lower improvement for acrylic coating properties, i.e. abrasion resistance, weathering durability, but the Ag/Zn zeolite particles expressed an excellent antibacterial activity. Hence, combination of the m-TiO2 nanoparticles and Ag/Zn zeolite particles could enhance the acrylic waterborne coatings' properties. The acrylic coating filled by 2 wt% m-TiO2 nanoparticles and 1 wt% Ag/Zn zeolite particles illustrated high abrasion resistance, good weather durability, and superior antibacterial activity for both of E. coli and S. aureus. This coating is promising for environmental friendly building materials application.

Environment-friendly clay coagulant aid for wastewater treatment

Wastewater management and its environment-friendly applications seem to be very complicated associated with chemical effects due to their dynamic characteristics for developing countries. Most of the world's agencies or countries have been treated wastewater using chemical coagulants which have contributed to other environmental complications. Considering the impacts of chemical coagulation, this study is novel research to identify alternative components that would be applied as a natural coagulant. The present study was conducted using two different regional clays as coagulants which were collected from Portugal and Bangladesh's Patuakhali coastal area. The clay coagulant applications were applied to investigate the removal efficiency of physical properties (turbidity), chemical properties (pH and COD), and heavy metals (Cr, Cd, Ni, and Pb) from wastewater. Comparatively, the highest removal efficiency was examined by the coastal clay of Patuakhali. This soil is also easily available in the local context and can be economically viable.

Investigation of the Disinfection Effect of Some Environmental Friendly Applications on Cotton Fabrics

ABSTRACT Today, the importance of health is kept on top of many things. Because people understood that neither the money they earn nor the life they live without their health is of any importance. Textile materials are together in every field during the day with us and they can be exposed to the attacks of microorganisms quite easily. Hence, ways of getting rid of these attacks in easy and environmental approaches should be considered in most cases. In this context, disinfection processes of textile products were investigated in this study. For this aim cotton fabrics were contaminated separately with two different types of bacteria. These bacterial species are Staphylococcus aureus (ATCC 29,213) and Escherichia coli (ATCC 25,922). Then bacterial contaminated fabric samples were treated with ozone and UV-C for different periods of time by a set of ozone and UV-C application system. Additionally hydrogen peroxide based disinfection has been tested as well. After these processes, bacterial reduction tests were carried out. In addition, SEM images of some fabric samples were taken to observe the surface modification. As a result, it was found that necessary and sufficient disinfection effect was obtained on cotton fabric in very short application time by using especially ozone gas.

Differential Effect of Anaerobic Digestion on Gaseous Products from Sequential Pyrolysis of Three Organic Solid Wastes.

Studies have shown that anaerobic digestion (AD) has an effect on the liquid and solid product property of sequential pyrolysis, but its influence on the gaseous products is lacking. In this study, syngas produced by pyrolysis from three raw organic solid wastes and the corresponding digestates, i.e., food waste, vinasse, and cow manure were investigated. AD causes a decrease in the contents of volatile solid, fixed carbon, C, H, and N and an increase in the S content. The weight loss of the wastes mainly occurs at 200–550 °C during the pyrolysis and the loss of the food waste and vinasse is higher than that of cow manure. In the carbon (C)-containing gas, AD leads to a decrease in the CH4 content of the syngas, implying that the heat values of the digestates are lower than that of the raw substrates. After AD, the total amount of nitrogen (N)-containing gas from the vinasse increases by 40.1%, while that from cow manure decreases by 14.1%. On the contrary, the total amount of sulfur (S)-containing groups in the syngas from vinasse drop by 22.0%, while that from cow manure increases by 9.1%. In addition, slight changes in the C-, N-, and S-containing gases are found from food waste. The results indicate that AD has a different effect on the N- and S- containing gaseous groups from different organic solid wastes, and the mechanisms deserve further investigation. The findings supply a theoretical foundation for environmental-friendly application of syngas from the digestates.

Investigation of tribological, physicomechanical, and morphological properties of resin-based friction materials reinforced with Agave americana waste

In recent years, natural fibers and their composites have attracted the attention of researchers due to environmental awareness and sustainable development. It is crucial to identify new natural fibers as potential reinforcement in polymer composites. This study was aimed to investigate the potential use of Agave americana fibers as a reinforcing component in resin-based friction materials. The tribological, physicomechanical, and morphological characteristics of materials containing different A. americana fiber contents were systematically evaluated. Experimental results indicated that fiber addition effectively improved the fade resistance, recovery behavior, and wear resistance of these materials. From the perspective of overall performance, a friction composite containing 5-wt% fibers possessed the optimal friction stability and wear resistance, exhibiting a fade rate of 13.6%, recovery rate of 97.5%, and sum wear rate of 2.340 × 10–7 cm3·N−1·m−1. Furthermore, sample worn surface morphologies were examined by scanning electron microscope, which revealed that appropriate fiber inclusion helped in the formation of secondary contact plateaus on friction surfaces. In addition, this fiber content significantly reduced abrasive and adhesive wear, which were conducive to good tribological behaviors of friction materials. This research provided a promising method for environment-friendly applications of A. americana waste.

Exploring the structural and optical properties of FeS filled graphene/PVA blend for environmental-friendly applications

Exploring the structural and optical properties of FeS filled graphene/PVA blend for environmental-friendly applications

Environmental friendly sustainable application of plant-based mordants for cotton dyeing using Arjun bark-based natural colorant.

Ecofriendly exploration of Arjun bark (Terminalia arjuna) is a herbal natural colorant for cotton dyeing. This is because the demand for natural dyes has been increased worldwide due to their therapeutic usage and other food, textiles, agriculture, engineering, and medical applications. Therefore, this study has been carried out due to the isolation of colorant from Arjun bark in an acidified methanolic medium after exposure to ultrasonic rays up to 60 min. Additionally, using bio-mordants, it has been found that the application of 10% of Zeera (Cuminum cyminum) extract as meta-bio-mordant, 3% of Ilaichi (Elettaria cardamomum) extract as meta-bio-mordant, and10 % of Harmal (Peganum harmala) and Neem (Azadirachta indica) extract as meta-bio-mordants has given excellent color strength. These bio-mordants have not only made the coloration process more eco-friendly, viable, and greener, but also improved color strength with various tonal effects from red to reddish brown shades. Thus, it has been found that ultrasonic treatment as an environment-friendly tool has not only enhanced the color strength of natural colorant isolated from Arjun bark onto the cotton fabric under mild conditions.

SnS2/Si nanowire vertical heterostructure for high performance ultra-low power broadband photodetector with excellent detectivity

Nanoparticle–nanowire heterostructures provide a new platform for photodetection applications owing to their higher light absorption, large responsivity, and excellent separation efficiency of photogenerated electron–hole pairs. Herein, we report a SnS2/Si nanowire heterostructure photodetector with excellent optoelectronic properties. A high-quality SnS2/Si nanowire heterostructure was prepared by simply spin coating a wet chemically synthesized SnS2 on a vertically standing Si nanowire made by metal assisted chemical etching. The as-prepared SnS2/Si nanowire heterostructure exhibits a robust p–n junction with excellent photodetector characteristics. The photodetector based on the heterostructure shows a photo-responsivity of ∼3.8 A W−1, a specific detectivity up to ∼ 2 × 1014 Jones, and an on/off ratio up to ∼ 102 at 340 nm illumination wavelength with a significantly low optical power density of 53.75 nW/mm2 at zero bias (0 V). The photo-responsivity reached its maximum value of ∼102 A/W and detectivity of ∼1 × 1014 Jones at the same wavelength with an applied bias of −2 V. In addition, the heterostructure photodetector provides significantly good photodetector key parameters (responsivity ∼5.3 A/W, detectivity ∼ 7.5 × 1012 Jones, rise/decay time ∼0.4/0.4 s) at −2 V bias over a wide spectral range from 400 to 1100 nm. The Si nanowire and SnS2 nanoparticle heterostructure devices with an enhanced junction area open up an exciting field for novel non-toxic and environmental friendly broadband optical detection applications and optoelectronic memory devices with high responsivity, ultrahigh sensitivity, and self-sufficient functionality at low power consumption and low cost with ease of processing.

Effect of Cu-doping on the structure, FT-IR and optical properties of Titania for environmental-friendly applications

In the present work, the effect of Cu-doping on the structure, FT-IR and optical properties of Titania has been explored for environmental-friendly applications. Cu-doped Titania thin films of different wt. % (0–24%) were synthesized using the spray pyrolysis technique. The surface morphology, structure, bonds’ vibrations and optical properties of the prepared thin films were studied using a scanning electron microscope, XRD analysis, FT-IR and UV–Vis.-NIR spectrophotometers respectively. The surface morphology and FT-IR spectra measurements ensure the active incorporation of Cu atoms in the host Titania matrix. The structural analysis reveals that all the prepared thin films match with the anatase phase structure of pure Titania. The absorption edges are red-shifted to the visible spectrum region as compared with that of the undoped one. 12 wt % of Cu-doped Titania is the optimal wt. % that reveals the highest visible light absorption. The direct energy bandgap (Egdir) of the prepared thin films decreases from 3.47 eV to 3.14 eV as the wt. % of Cu-doped Titania increases from 0 to 12%, and then it rises again to 3.42 eV as the wt. % of Cu is increased up to 24%. Consequently ,Egdir of Titania has been tailored via Cu-doping to cover the visible light spectrum for environmentally-friendly applications.

Studies of carboxylated nitrile butadiene rubber/butyl reclaimed rubber (XNBR/BRR) blends for shoe soles application

Abstract Rising environmental issues and huge disposal of rubber waste have resulted in an increased interest in the usage of reclaimed rubber (RR) to produce sustainable and environmental friendly applications. In this study, incorporation of butyl reclaimed rubber into carboxylated nitrile butadiene rubber (XNBR/BRR) was carried out where the loadings of each XNBR and BRR were varied. The rubber was cured with sulphur during the melt mixing using a two-roll mill. This study is aimed to investigate the applied BRR loading towards the physical and mechanical properties of the XNBRcompounds. The results appeared that the optimum cure time (T90) increased and curing rate index (CRI) showed that a faster curing reaction with the increase in the content of BRR where the T90 had an increment of 89% while the CRI was faster by 89%. As for the crosslink density which indicates the density of chains or segments in polymer network, it decreased about 20% with increasing level of BRR. Also, the compression set which refers to the ability of rubber to resist permanent deformation, had an increase of 73% as the loading ratio of BRR increased. These results were obtained due to the low molecular weight of the BRR where the high shear and temperature during the reclamation process severely breaks down the molecular chains of the BRR into shorter segments. With the results obtained, it is shown that reclaimed rubber has the potential for further development and could increase the interest of researchers all around the world in the incorporation of reclaimed rubber for footwear application.

Environmental friendly application of ultrasonic rays for extraction of natural colorant from Harmal (P. harmala) for dyeing of bio-mordanted silk

Global heat, carcinogenic, and viral diseases created due to industrial pollutants has led people to shift toward natural products particularly natural dyes in all walks of life. In this study, U.S. rays up-to 60 min, were used to extract the color in aqueous medium and employed onto silk fabric at selected conditions. It has been observed that good color strength has been found when 30 mL of acidic extract ( pH = 4.0) obtained from 6.0 g of Harmal powder containing 3.0 g/100 mL of salt as an exhausting agent was employed onto the US treated silk at 65ºC for 55 min. The utilization of the extract obtained from 7% of pomegranate as post-bio-mordant, 3% of acacia extract as meta-bio-mordant, and 7% of henna extract as meta-bio-mordants has given excellent color strength. In comparison, 5% of Al salt as meta mordant, 5% of Fe salt as pre mordant, and 7% of tannic acid as meta-mordant has given better results. ISO standard methods for fastness employed onto optimum mordanted dyed fabrics have given well to excellent fastness ratings. Hence, natural colorant extracted from Harmal seeds has excellent coloring efficacy to dye silk fabric under sustainable conditions, whereas the addition of eco-friendly mordants for shade development process has made the coloration of silk more sustainable with improved colorfastness properties.

Biochar industry to circular economy

Biochar, produced as a by-product of pyrolysis/gasification of waste biomass, shows great potential to reduce the environment impact, address the climate change issue, and establish a circular economy model. Despite the promising outlook, the research on the benefits of biochar remains highly debated. This has been attributed to the heterogeneity of biochar itself, with its inherent physical, chemical and biological properties highly influenced by production variables such as feedstock types and treating conditions. Hence, to enable meaningful comparison of results, establishment of an agreed international standard to govern the production of biochar for specific uses is necessary. In this study, we analyzed four key uses of biochar: 1) in agriculture and horticulture, 2) as construction material, 3) as activated carbon, and 4) in anaerobic digestion. Then the guidelines for the properties of biochar, especially for the concentrations of toxic heavy metals, for its environmental friendly application were proposed in the context of Singapore. The international status of the biochar industry code of practice, feedback from Singapore local industry and government agencies, as well as future perspectives for the biochar industry were explained.

Selective oxidation of toluene to benzaldehyde over Pd/BiVO4 particles under blue to green light irradiation

Selective synthesis of organic chemicals such as oxidation of toluene to benzaldehyde using sunlight is necessary for its sustainable and environment-friendly applications. The photocatalytic reaction using semiconductor photocatalysts is a promising approach for sunlight-induced organic synthesis due to its significant advantages of operation under mild conditions, stability, and recyclicity. TiO2 is one of the most widely studied photocatalysts; however, the low selectivity for partial oxidation due to the complete decomposition to CO2 and lack of utilization of visible-light hampers its practical application. Here, we successfully demonstrated selective oxidation of toluene to benzaldehyde using a Pd-loaded BiVO4 photocatalyst under visible light irradiation. Furthermore, we confirmed that the reaction proceeds even under light irradiation up to 520 nm; this is the first report using blue-to-green light-responsive semiconductor photocatalyst for converting toluene to benzaldehyde. Achieving efficient organic synthesis under visible light using semiconductor photocatalyst is an important step toward solar-to-chemical conversion.