Waste By-product Research Articles

Effect of lightweight composite brick’s waste on the removal of malachite green from aqueous solution and phytotoxicity assessment

ABSTRACT This study investigates the removal of malachite green (MG) dye by adsorption process using as adsorbent a waste byproduct from lightweight composite brick production, composed of clay and 5 wt.% argan nut shell and designed as waste bricks (WB). Characterization of the adsorbent (WB) was conducted using several techniques such as XRD, XRF, FTIR, etc. Optimal conditions for the adsorption process of MG dye with WB were carried out, considering adsorbent dose (0.02–0.4 g/mL), pH (2–12), contact time (0–360 min), and MG dye concentration (20–210 mg/L). The obtained outcomes indicated that the optimal parameters for a dye concentration of 20 mg/L are an adsorbent dose of 0.15 g/mL, a pH of 10, and an adsorption time of 180 minutes. Furthermore, kinetic, isotherm, and thermodynamic adsorption have been evaluated. The results highlighted that the pseudo second-order and Langmuir model described accurately the adsorption process with an adsorption capacity of about 2.66 mg/g and 23.48 mg/g respectively. While the thermodynamic study conducted at four temperatures (298 K, 308 K, 318 K, 328 K) revealed that the adsorption process is spontaneous and endothermic in nature. Finally, a phytotoxicity test of malachite green dye solutions was carried out using wheat and lentil seeds confirming the treatment effectiveness of the adsorbent.

Preparation and mechanical characterization of natural polymer composite material obtained from fox tail palm seeds

This experimental investigation reveals the preparation of natural composite material from foxtail palm tree seeds. The fruits from the foxtail palm tree are used for the extraction of oil, and the by-product of the extraction process is freely dumped. This study attempts to utilize the waste by-product of foxtail palm tree fruit as a valuable natural composite material. The fabrication was done using the hand lay-up method for the proposed reinforcement (4% and 8%) of filler materials. The obtained composite materials are subjected to significant mechanical characterization of tensile behaviour, flexural property, and hardness. In addition, the morphological study was also carried out by the scanning electron microscope (SEM). The results show that, as the reinforcement percentages of filler material increase, the mechanical properties are improved. This may be due to the uniform dispersion of natural fibres in the polymer. The tensile strength was improved by 22.43% and 29.08% for 4% and 8% filler reinforcement. Similarly, the stiffness property was improved by 9.32% for 4% reinforcement and 18.68% for 8% reinforcement when compared with neat composite. The SEM images reveal the failure analysis, bonding strength and fibre pull-out in the composites. Finally, the foxtail fruit fibre shows promise as a reinforcing agent in composite materials, improving their mechanical properties and making them suitable for various applications requiring strength, stiffness, and resistance to deformation.

Synthesis and characterization of bagasse cellulose-based quaternary ammonium peroxyphosphotungstate and their catalytic properties for cyclohexene oxidation in the absence of any solvent

Bagasse cellulose, an industrial waste byproduct of sugar production, was demonstrated to be a viable solid support for a solid-phase ionic oxidation catalyst enabling organic solvent-free aqueous reaction conditions and facile catalyst recovery. Bagasse cellulose-supported quaternary ammonium peroxyphosphotungstate was synthesized from bagasse cellulose-supported quaternary ammonium chloride, phosphotungstic acid, and hydrogen peroxide. The chemical structure of this material was characterized by SEM, XRD, FT-IR, XPS, and 13C NMR, revealing stability of the cellulose matrix to the catalyst loading conditions and effective dispersion of the acicular catalyst crystals throughout the matrix. High catalytic activity of this synthetic complex was demonstrated in the oxidation of cyclohexene to 1,2-cyclohexanediol with hydrogen peroxide in the absence of solvent. Optimized conditions providing trans-1,2-cyclohexanediol with 86.2 % selectivity were 12 wt% catalyst and 4 mL/g 30 % H2O2 (vs. cyclohexene) at 50 °C for 10 h.

Investigating the mechanical and physical properties of lightweight geopolymer concrete

Using waste materials and by-products from various building sectors is gaining popularity because natural resources are quickly depleting. Geopolymer concrete is made from by-product material and is a relatively new environmental material that does not require the presence of ordinary Portland cement as a binder. This study involves producing lightweight geopolymer concretes using a slag binder and replacing the conventional fine and coarse aggregates with two types of locally available lightweight aggregate (thermostone and montmorillonite). Several sequential steps were used to process the aggregates, along with a series of tests conducted to evaluate the concrete properties in different states. The fresh state test includes the slump test, while the hardened concrete tests involve compressive strength, flexural strength, density, thermal conductivity, and water absorption. This study reveals the suitability of lightweight concrete mixtures for various constructional applications. The most reliable mixture was the GMM, which consisted of coarse montmorillonite (5–25 mm) and fine montmorillonite aggregates. This mixture exhibited the highest compressive strength of 23.3 MPa, a flexural strength of 3.25 MPa compared to other LWGC mixtures, and a low density of 1785 kg/m3. The GMM density was 23.97% lower than the reference mixture, whereas the thermal insulation significantly improved by 65.58%. Consequently, this improvement was evident in the thermal conductivity coefficient, which measured as approximately 0.349 W/m.K. In addition, the GTT mixture containing thermostone aggregate (5-25 mm) yielded the most optimal thermal insulation and lowest density of 0.267 W/m.K and 1552 kg/m3, respectively. In general, the strength and density of the LWGC mixtures in this study meet the requirements of lightweight structural applications.

Developing an eco-friendly cementitious grout using paper sludge ash and steel fiber recovered from waste tires

Cement is the most important component in cementitious grout production,andtt accounts for 7% of global greenhouse gas emissions. Reducing the amount of cement used in infrastructure and buildings is a desirable way to lower the total carbon footprint associated with grout production. relatedly, developments in manufacturing and transportation lead to the production of cars in large numbers, which in turn leads to an increase in the production of byproduct waste like waste tires, which are thrown away directly without recycling. Thus, this study aims to develop a novel sustainable grout by recycling paper sludge ash waste (PSA) and waste steel fiber (WSF) as partial cement replacements. This will help reduce grout production costs, minimize environmental pollution during cement production, and enhance landfill and waste management. The Grout mixtures used in this paper were prepared using ordinary Portland cement (OPC), WSF extracted from vehicle tires, PSA, and water. Different proportions of WSF(0, 1, 2, 3%) and PSA(5, 10%) were used in the weight of cement in designing sustainable grout. The mechanical properties of the sustainable grout were evaluated by examining extensive tests including flow tables, compressive strength, and flexural strength. The results showed that partially replacing the cement with 3% WSF and 1% WSP with 5% PSA resulted in a significant improvement in workability ,as well as a clear increase in compressive and flexural strength at an early age compared to the reference mixture.

Experimental investigation on properties of gold tailings recycled brick-concrete aggregate concrete under microwave curing

Tailings are the low-value solid waste by-products, which can be expected to serve as sustainable material through activation. In this study, activated gold tailings (GT) were utilized as supplementary cementitious materials to produce GT-cement slurry and gold tailings recycled brick-concrete aggregate (GT-RBCA) concrete. By varying curing methods including microwave curing and steam curing, the effects of resting time and curing temperature on compressive strength of GT-cement slurry specimens were experimentally analyzed. Also, X-ray diffraction (XRD) and scanning electron microscopy (SEM) were employed to analyze the hydration products and microstructure. Additionally, the compressive strength of GT concrete including GT-RBCA concrete under these curing methods were explored, followed by an assessment of environmental and economic benefits. The results demonstrated that a curing temperature around 40 °C with microwave method and 10%–20 % GT will benefit the strength development of GT-cement slurry specimens, reach the highest 28-day compressive strength of 42.6 MPa compared with steam curing and standard curing. This could be attributed to the “hot spot" effect of GT under microwave curing, leading to effective promotion of the pozzolanic reaction and subsequent enhancement of the hydration reaction. For GT-RBCA concrete, microwave curing exhibited the best effect on early compressive strength of GT-RBCA concrete compared with other curing methods. Particularly, whether the standard water-cement ratio condition (w/c = 0.42) or the low water-cement ratio condition (w/c = 0.35), GT-RBCA concrete under microwave curing at 40 °C and 10 % gold tailings substitution rate, achieved a maximum 12.3 % increase in 28-day compressive strength compared to steam curing and standard curing conditions. In addition, the GT-RBCA concrete under microwave curing obtained 11.7 % CO2 emissions reduction compared with steam curing.

Advances in Extraction, Structure, and Physiochemical Properties of Sorghum Kafirin for Biomaterial Applications: A Review.

Kafirin is an endosperm-specific hydrophobic protein found in sorghum grain and the waste by-product from sorghum biorefineries known as sorghum dried distillers' grain with solubles (DDGS). Because of kafirin's poor nutritional profile (negative nitrogen balance, slow digestibility, and lack of some essential amino acids), its direct human use as a food is restricted. Nevertheless, increased focus on biofuel production from sorghum grain has triggered a new wave of research to use sorghum DDGS kafirin as a food-grade protein for biomaterials with diverse applications. These applications result from kafirin's unique chemical nature: high hydrophobicity, evaporation-induced self-assembling capacity, elongated conformation, water insolubility, and low digestibility. Aqueous alcohol mixtures have been widely used for the extraction of kafirin. The composition, structure, extraction methodologies, and physiochemical properties of kafirin, emphasising its biomaterial functionality, are discussed in detail in this review. The literature survey reveals an in-depth understanding of extraction methodologies and their impact on structure functionality, which could assist in formulating materials of kafirin at a commercial scale. Ongoing research continues to explore the potential of kafirin and optimise its utilisation as a functional biomaterial, highlighting its valuable structural and physicochemical properties. Further studies should focus on covering gaps in the research as some of the current structural understanding comes from data on zein protein from maize.

Effect of blanching conditions and solar drying on selected nutritional, anti-nutritional and bioactive components of formulated avocado seed powder

Avocado (Persea americana Mill) seeds are mainly considered as waste by-products of avocado fruit processing in many countries, including Tanzania despite their potential health and economic benefits. The present work investigated the effect of hot water blanching and solar drying treatments on nutritional, bioactive, and cyanogenic glycosides of avocado seed samples in an attempt to develop quality avocado seed powders (ASPs) by using solar drying technology. Results showed that total ash, crude protein, crude fiber, total phenolic, proanthocyanidins, and cyanogenic glycosides contents showed a significant reduction in avocado seed powders with respect to increased blanching temperature and time. On the other hand, crude fat and total carotenoids contents, showed a decline with respect to increased temperature only. Blanching treatment at 85 °C for 10 minutes retained a significant amount of total ash (86.9%), crude fat (100%), crude protein (78.8%), crude fiber (91.6%), total carotenoids (43.6%) and total phenol contents (47.0%) in developed avocado seed powder. Cyanogenic glycosides were highly reduced at 95 °C for 20 minutes (81.1%) than at 85 °C for 10 minutes (58.5%). However, the level of cyanogenic glycosides in all avocado seed powders are far below the lethal dose (36 mg/100 g) of hydrocyanic acid. The significant high losses of nutrients and phytochemicals was observed at a blanching treatment of 95 °C for 20 minutes. This could be due to prolonged leaching of soluble compounds to hot water and degradation of heat-sensitive bioactive compounds. The aforementioned results revealed that, different temperatures and times during hot water blanching significantly influence the quality of formulated avocado seed powder. Therefore, hot water blanching treatment at 85 °C for 10 minutes and solar drying technology could be employed to produce a nutrient-rich and palatable avocado seed powder that can find its use in normal food consumption and food processing industries, particularly in low income settings. Key words: Avocado seed, avocado seed powder, solar drying, hot water blanching, utilization

Evaluation of Thermal and Mechanical Properties of Foamed Phosphogypsum-Based Cementitious Materials for Well Cementing in Hydrate Reservoirs

As detrimental byproduct waste generated during the production of fertilizers, phosphogypsum can be harmlessly treated by producing phosphogypsum-based cementitious materials (PGCs) for offshore well cementing in hydrate reservoirs. To be specific, the excellent mechanical properties of PGCs significantly promote wellbore stability. And the preeminent temperature control performance of PGCs helps to control undesirable gas channeling, increasing the formation stability of natural gas hydrate (NGH) reservoirs. Notably, to further enhance temperature control performance, foaming agents are added to PGCs to increase porosity, which however reduces the compressive strength and increases the risk of wellbore instability. Therefore, the synergetic effect between temperature control performance and mechanical properties should be quantitatively evaluated to enhance the overall performance of foamed PGCs for well cementing in NGH reservoirs. But so far, most existing studies of foamed PGCs are limited to experimental work and ignore the synergetic effect. Motivated by this, we combine experimental work with theoretical work to investigate the correlations between the porosity, temperature control performance, and mechanical properties of foamed PGCs. Specifically, the thermal conductivity and compressive strength of foamed PGCs are accurately determined through experimental measurements, then theoretical models are proposed to make up for the non-repeatability of experiments. The results show that, when the porosity increases from 6% to 70%, the 7 d and 28 d compressive strengths of foamed PGCs respectively decrease from 21.3 MPa to 0.9 MPa and from 23.5 MPa to 1.0 MPa, and the thermal conductivity decreases from 0.33 W·m−1·K−1 to 0.12 W·m−1·K−1. Additionally, an overall performance index evaluation system is established, advancing the application of foamed PGCs for well cementing in NGH reservoirs and promoting the recycling of phosphogypsum.

Exploring the Future of Polyhydroxyalkanoate Composites with Organic Fillers: A Review of Challenges and Opportunities.

Biopolymers from renewable materials are promising alternatives to the traditional petroleum-based plastics used today, although they face limitations in terms of performance and processability. Natural fillers have been identified as a strategic route to create sustainable composites, and natural fillers in the form of waste by-products have received particular attention. Consequently, the primary focus of this article is to offer a broad overview of recent breakthroughs in environmentally friendly Polhydroxyalkanoate (PHA) polymers and their composites. PHAs are aliphatic polyesters obtained by bacterial fermentation of sugars and fatty acids and are considered to play a key role in addressing sustainability challenges to replace traditional plastics in various industrial sectors. Moreover, the article examines the potential of biodegradable polymers and polymer composites, with a specific emphasis on natural composite materials, current trends, and future market prospects. Increased environmental concerns are driving discussions on the importance of integrating biodegradable materials with natural fillers in our daily use, emphasizing the need for clear frameworks and economic incentives to support the use of these materials. Finally, it highlights the indispensable need for ongoing research and development efforts to address environmental challenges in the polymer sector, reflecting a growing interest in sustainable materials across all industries.

Sustainable Synthesis of the Active Pharmaceutical Ingredient Atenolol in Deep Eutectic Solvents.

Atenolol, one of the top five best-selling drugs in the world today used to treat angina and hypertension, and to reduce the risk of death after a heart attack, faces challenges in current synthetic methods to address inefficiencies and environmental concerns. The traditional synthesis of this drug involves a process that generates a large amount of waste and other by-products that need disposal. This study presents a one-pot DES-based sustainable protocol for synthesizing atenolol. The use of the DES allowed the entire process to be conducted with no need for additional bases or catalysts, in short reaction times, under mild conditions, and avoiding chromatographic purification. The overall yield of atenolol was 95%. The scalability of the process to gram-scale production was successfully demonstrated, emphasizing its potential in industrial applications. Finally, the 'greenness' evaluation, performed using the First Pass CHEM21 Metrics Toolkit, highlighted the superiority in terms of the atom economy, the reaction mass efficiency, and the overall process mass intensity of the DES-based synthesis compared with the already existing methods.

Unveiling the "hidden quality" of the walnut pellicle: a precious source of bioactive lipids.

Tree nut consumption has been widely associated with various health benefits, with walnuts, in particular, being linked with improved cardiovascular and neurological health. These benefits have been attributed to walnuts' vast array of phenolic antioxidants and abundant polyunsaturated fatty acids. However, recent studies have revealed unexpected clinical outcomes related to walnut consumption, which cannot be explained simply with the aforementioned molecular hallmarks. With the goal of discovering potential molecular sources of these unexplained clinical outcomes, an exploratory untargeted metabolomics analysis of the isolated walnut pellicle was conducted. This analysis revealed a myriad of unusual lipids, including oxylipins and endocannabinoids. These lipid classes, which are likely present in the pellicle to enhance the seeds' defenses due to their antimicrobial properties, also have known potent bioactivities as mammalian signaling molecules and homeostatic regulators. Given the potential value of this tissue for human health, with respect to its "bioactive" lipid fraction, we sought to quantify the amounts of these compounds in pellicle-enriched waste by-products of mechanized walnut processing in California. An impressive repertoire of these compounds was revealed in these matrices, and in notably significant concentrations. This discovery establishes these low-value agriculture wastes promising candidates for valorization and translation into high-value, health-promoting products; as these molecules represent a potential explanation for the unexpected clinical outcomes of walnut consumption. This "hidden quality" of the walnut pellicle may encourage further consumption of walnuts, and walnut industries may benefit from a revaluation of abundant pellicle-enriched waste streams, leading to increased sustainability and profitability through waste upcycling.

Optimizing coolant oil wastewater treatment via modified air-Fenton process with bimetallic particles from auto parts manufacturing waste

This study evaluated the efficiency of aluminium (Al)/iron (Fe) bimetallic particles, produced from waste by-products of auto parts manufacturing—namely, aluminum dross (AD) and shot blast (SB)—in removing chemical oxygen demand (COD) and total organic carbon (TOC) from coolant oil wastewater originating from an auto parts manufacturer. Two different molar ratios of ADSB bimetallic particles, namely, 1:1 (ADSB1) and 2:1 (ADSB2), were investigated for their characteristics and applied in the modified air-Fenton (MAF) process which enhances the traditional Fenton method by utilizing ADSB bimetallic particles instead of Fe0 and Al0, and by incorporating aeration to stimulate the reaction. The wastewater contained an initial COD ranging from 60,000 to 120,000 mg L–1 (at 3–5 % v/v) and a TOC ranging from 10,000 to 40,000 mg L−1. The experimental design included varying reaction times, pH values, quantities of bimetallic particles, airflow rates, and wastewater concentrations were performed using the Minitab-19 software package. X-ray fluorescence (XRF) analysis revealed that the bimetallic particles have SiO2 content ranging from 39.69 % to 56.03 %, Fe2O3 ranging from 20.52 % to 30.90 % and Al2O3 ranging from 16.51 % to 16.66 %, with surface areas varying between 5 and 6 m2 g−1. As a result of XRF analysis, SiO2 can be contaminated by the sand molds used in the manufacturing process of products. Notably, ADSB1 exhibited impressive removal efficiencies of 98.70 % and 98.50 % for COD and TOC, respectively, at 0.6 g, pH 3, airflow rate of 1.5 L min–1, and reaction time of 105 min. Conversely, ADSB2 achieved removal efficiencies of 96.30 % and 98.43 % for COD and TOC, respectively, at 0.2 g, pH 9, airflow rate of 2.0 L min–1, and reaction time of 180 min. Pareto charts and 3D surface plots derived from the data showed the number of bimetallic particles as the most influential factor, followed by the initial pH. The MAF process significantly extends the pH range under diverse conditions by incorporating ADSB particles and reduces the reliance on traditional chemicals like hydrogen peroxide. This research presents a promising advancement in wastewater treatment technology.

Inorganic phosphorous availability and mobility in a manufactured soil

Manufactured soils, created by combining various organic and inorganic waste materials and byproducts, may be tailored to specific applications, providing an alternative to the extraction of natural soils. It is important for them to be capable of supporting plant growth without the need for significant management or fertiliser applications, the over-application of which can have adverse environmental effects.We examined the dynamics of phosphorus (P) transformations within a manufactured soil and the implications for nutrient cycling. A freshly prepared manufactured soil (32.5 % composted green waste, 32.5 % composted bark, 25 % horticultural grit, and 10 % lignite clay) was studied over one year in temperature and moisture controlled mesocosms. Leachate was collected to achieve high-resolution monitoring of leached phosphate concentrations.Initially, leached dissolved inorganic phosphorus (DIP) concentrations were low (0.02 ± 0.01 mg P L−1), before increasing by 160 μg P L−1 d−1 over the first 42 days to 5.57 ± 1.23 mg P L−1. After reaching a maximum concentration, DIP concentrations remained relatively consistent, varying by only 1.67 mg P L−1 until day 270. The increase in leached DIP was likely driven by soil organic matter mineralisation and the cleavage of carbon‑phosphorus bonds by the soil microbes to satisfy carbon demand with mineralogical influences, such as a decrease in apatite content, also contributing. Sorption and desorption from soil particles were the processes behind the P loss from the soil, which was followed by slow diffusion and eventual loss via leaching. The fertiliser application on phosphate dynamics resulted in increased DIP leaching.P concentrations observed in the manufactured soil were within the range considered sufficient to support plant growth. However, the mean leached phosphorus concentrations were higher than reported eutrophication thresholds suggesting that these soils may pose a risk to surface waters in their current form.

Large-Scale Conversion of Livestock Blood into Amino Acid Liquid Fertilizer and Dry Protein Feedstuff: A Case Study

Livestock blood, typically considered a waste byproduct of the slaughter industry, has the potential to be a valuable resource in the environmental and agricultural industries owing to its high protein content. This study reports the mechanisms involved in developing a continuous process capable of processing 5 tons/day of livestock blood into high purity amino acid liquid fertilizer and dried protein feedstuff simultaneously. Large-scale processing units were fabricated for the ultrasonic pretreatment and solubilization of proteins, enzymatic degradation of dissolved proteins for amino acid conversion, solid-liquid separation using a membrane filter press to produce high purity amino acid liquid fertilizer, and microwave drying of the solid component to produce dry protein feedstuff. The main processing units were integrated into a continuous, efficient system. The final amino acid liquid fertilizer and dry protein feedstuff contained >20% amino acids and approximately 78% protein, respectively. An economic feasibility analysis of the integrated system based on an annual processing capacity of 3000 tons of livestock blood yielded a total annual profit of 17.4 million euros (5812 euros/ton). This study presents an efficient and profitable approach to repurposing the waste generated by slaughterhouses toward agriculture and feed production.

Tunable dye adsorbing materials from crab and shrimp waste shells for water remediation

Crab and shrimp shells are waste byproducts from shellfish farming and processing. In this study, we demonstrated that it is possible to obtain individual shell components either separately or in combinations. These diverse materials were composed of calcium carbonate and organic molecules inter- and intra-mineral, calcium carbonate and organic molecules intra-mineral, organic molecules such as chitin and proteins, only calcium carbonate, and only chitin. These substrates were tested for the adsorption of Methylene Blue and Eosin dyes. The goal is to demonstrate that the organic dye adsorption capacity can be modified by controlling the degree of deconstruction of the starting material. The best adsorption for the positively charged Methylene Blue was achieved on the chitin-calcium carbonate substrates, while the negatively charged Eosin adsorbed best on the chitin substrate. In conclusion, this research demonstrates that it is possible to obtain different materials by deconstructing the shells from crabs and shrimps at various levels reducing the generation of additional wastes. Moreover, these materials exhibit features that are related to the original material and possess new properties that can be also exploited in other fields like material sciences.

Performance Evaluation of Self-Compacting Concrete Prepared Using Waste Foundry Sand on Engineering Properties and Life Cycle Assessment

The primary objective of this research is to utilize an industrial waste byproduct such as waste foundry sand (WFS) as an alternative for fine aggregate in self-compacting concrete (SCC). This research focuses on the use of WFS in SCC to enhance durability and mechanical properties, to find an alternative for fine aggregate in SCC, to reduce the disposal challenges of WFS, and to make SCC lightweight and environmentally friendly. Initially, WFS was treated with chemical (H2SO4), segregating, and sieving to remove the foreign matter and clay content. For this study, WFS is considered in varying percentages such as 0, 10, 20, 30, 40, and 50. For this investigation, M60 grade SCC is considered as per Indian standards and EFNARC guidelines. After that, this research focuses on tests on various fresh properties of SCC in each batch to find the flowability and passing ability of various mixes prepared using WFS. Similarly, the mechanical properties of SCC such as compressive, flexural, and split tensile strength tests were performed at 7, 28, and 90 days curing periods, respectively. Likewise, durability properties of SCC were found in all the mixes prepared using WFS such as water absorption, sorptivity, resistance to chemical attack, and chloride ion penetration; tests of these properties were performed at 28 and 90 days curing periods, respectively. Based on the experimental investigation of SCC, it was found that WFS can be used in M60 grade SCC as an alternative for fine aggregate up to 30% without compromising much on its properties. Finally, this establishes that using treated WFS in SCC helps in reducing the generation of waste and prevails as a meaningful utilization method. This research will also establish that the use of treated WFS will reduce the density and make SCC a lightweight, green, and sustainable material.

A Review on durability and microstructure of Fly-Ash based geopolymer concrete (FA-GPC)

Concrete, being the fundamental material in the construction industry, relies largely on cement for its structural integrity and performance. However, new researches have emphasized a significant concern—the considerable increase in global greenhouse gas emissions linked to cement manufacturing. This rise in emissions derives mostly from the thermal decomposition of calcium carbonate during the clinkering process, establishing cement as a key contributor to the rising CO2 footprint. This alarming trend demands prompt attention and inventive remedies. This study intends to solve this important environmental issue by studying the transformational potential of Geopolymer Concrete (GPC) as a sustainable alternative. By adding FA, an abundant industrial waste by-product, as a supplementary cementitious material (SCM) in GPC, we have the possibility to dramatically cut carbon emissions by up to 80%.This transition towards sustainable materials not only decreases the load on traditional cement resources but also illustrates how waste materials may be utilized for the sake of the environment. Our analysis comprises factors such as consistency, curing temperature, chloride corrosion resistance, XRD (X-ray Diffraction) and SEM (Scanning Electron Microscopy) investigations. Through these findings, we hope to underline the considerable potential of GPC, particularly when strengthened with FA, as a strong tool for decreasing the carbon footprint within the building sector.

Comparison of Aroma and Taste Profiles of Kiwi Wine Fermented with/without Peel by Combining Intelligent Sensory, Gas Chromatography-Mass Spectrometry, and Proton Nuclear Magnetic Resonance.

Kiwi wine (KW) is tipically made by fermenting juice from peeled kiwifruit, resulting in the disposal of peel and pomace as by-products. However, the peel contains various beneficial compounds, like phenols and flavonoids. Since the peel is edible and rich in these compounds, incorporating it into the fermentation process of KW presents a potential solution to minimize by-product waste. This study compared the aroma and taste profiles of KW from peeled (PKW) and unpeeled (UKW) kiwifruits by combining intelligent sensory technology, GC-MS, and 1H-NMR. Focusing on aroma profiles, 75 volatile organic compounds (VOCs) were identified in KW fermented with peel, and 73 VOCs in KW without peel, with 62 VOCs common to both. Among these compounds, rose oxide, D-citronellol, and bornylene were more abundant in UKW, while hexyl acetate, isoamyl acetate, and 2,4,5-trichlorobenzene were significantly higher in PKW. For taste profiles, E-tongue analysis revealed differences in the taste profiles of KW from the two sources. A total of 74 molecules were characterized using 1H-NMR. UKW exhibited significantly higher levels of tartrate, galactarate, N-acetylserotonin, 4-hydroxy-3-methoxymandelate, fumarate, and N-acetylglycine, along with a significantly lower level of oxypurinol compared to PKW. This study seeks to develop the theoretical understanding of the fermentation of kiwifruit with peel in sight of the utilization of the whole fruit for KW production, to increase the economic value of kiwifruit production.

Novel Synthesis of Nanocalcite from Phosphogypsum and Cesium Carbonate: Control and Optimization of Particle Size

This study investigates a controlled synthesis and particle size optimization of nanocalcite particles using phosphogypsum, a waste byproduct from the phosphate fertilizer industry, and cesium carbonate (Cs2CO3), a common carbonate source. The effects of synthesis parameters, including temperature and pH, on the size, morphology, and crystallinity of the synthesized nanocalcite particles were systematically examined. The optimized synthesis conditions for obtaining nanocalcite particles with desired properties are discussed. The synthesized nanocalcite particles were characterized using various techniques, such as XRD, FTIR, and SEM, to analyze their crystal structure, morphology, and elemental composition. Particle sizes were determined using the Debye–Scherrer method, and accordingly, nanometric sizes were achieved. The potential applications of the synthesized nanocalcite particles in cementitious materials, agriculture, and drug delivery are highlighted. This research provides valuable insights into the sustainable synthesis and size optimization of nanocalcite particles from phosphogypsum and Cs2CO3 at a controlled temperature and pH.