Recycling Of Industrial Waste Research Articles

Iron-rich industrial waste enhanced low-carbon radiation shielding functional composites

Recycling of industrial wastes into value-added functional materials is a sustainable route for industrial waste management. This study proposed a revolutionary design of low-carbon radiation shielding functional composites by incorporating iron-rich industrial waste as precursor and heavy aggregates. Experimental results showed that the iron-rich industrial waste-enhanced radiation shielding functional composites (IWRSC) reached a high compressive strength of 43.2 MPa after 3-day heat curing. Characterization analyses indicated that the alkali-active components dissolved from industrial waste aggregates reacted with the alkali-activator to generate abundant geopolymer gels, resulted in the improvement in the interfacial transition zone. Besides, the gamma ray shielding capability of IWRSC was 21.2% better than that of normal composite, due to the high density of industrial waste aggregates and the dense microstructure of IWRSC. The carbon emission and energy consumption of composites were reduced by 64.4% and 69.6% by replacing natural heavy aggregates with industrial waste heavy aggregates. The unit cost of IWRSC was only 95.9 $/m3, which was 95.0% lower than that of barite-incorporated counterpart. Thus, this novel solution can effectively recycle industrial wastes into functional composites in a sustainable way, contributing to zero-waste city construction and the realization of a circular economy.

Effect of Strapping Straps Waste Fibers on Fresh and Hardened Properties of Concrete

Abstract Faced with the increasingly growing need for construction material resources and the strict requirements and conditions for preserving the environment, it has become necessary and relevant to study all possibilities and opportunities for the recycling and valorization of industrial waste and by-products in the construction field. Strapping straps is a product used to bundle and transport goods and construction materials. After its use, it is considered as waste. The objective of this experimental work is to study the possibility of reusing the strapping strap waste as fibers in the production of fiber-reinforced concrete. For this purpose, three families of concrete were composed using strapping strap fibers, steel fibers, and polypropylene fibers, which were introduced into a concrete composition by volumetric substitution (0.4%, 0.8% and 1.2%) of aggregates. The fresh properties were evaluated through slump, density and air content tests. Hardened properties were investigated using the compressive and flexural strengths, pulse velocity, dynamic elastic modulus, and water absorption tests. The results obtained showed that strapping strap waste fibers significantly improve the mechanical properties of fiber-reinforced concrete and have a behavior similar to that of steel fibers. The optimum rates of strapping strap fibers were 0.4% and 1.2% for compressive and flexural strengths respectively. Compared to polypropylene fibers, the strapping strap fibers were found to be more efficient and led to a gradual increase in flexural strength with an increase in the strapping strap fibers. The results obtained also showed that the increase in strapping strap fiber content gradually increased the water absorption of fiber-reinforced concrete.

In-situ wet carbonation activation of red mud waste for sustainable grout materials

The low reactivity and high alkalinity of raw red mud (RRM) limit its utilization as supplementary cementitious materials (SCMs) in Portland cement-based grouts. This work develops an in-situ wet carbonation technique to improve the chemical reactivity of RRM using flue gas CO2. Systematic investigation of the RRM before and after carbonation revealed transformed composition and microstructure. The minerals and morphology changed significantly, with nano-CaCO3 and amorphous silica/silica-alumina gels formation. This enhanced the pozzolanic reactivity of RRM. Detailed evaluation of the effects of carbonated red mud (CRM) as SCMs on the properties of Portland cement-based grouts showed accelerated hydration kinetics and refined pore structure. Replacement of 30% cement by the CRM increased the 28 d compressive strength of the grout. The underlying mechanisms were analyzed via XRF, XRD, TGA, FT-IR, 29Si NMR, SEM, and N2 adsorption–desorption testing. The nano-CaCO3 and silica/silica-alumina gels from CRM participated in additional hydration and microstructure densification. This integrated approach enables the improved performance of grouting materials through CO2 mineralization and industrial waste recycling.

Recycling of different industrial wastes as supplement of cement for sustainable production of mortar

Day by day, soaring demand for natural resource devouring and CO2-producing material, cement in the construction industry, poses enormous ecological risk, accelerating the requirement of an alternative or supplementary cementitious material (SCM). In contrast, retrieval of a massive amount of industrial waste needs proper attention to alleviate the environmental burden. This research aims to utilize three common industrial wastes: recycled concrete dust (RCD), ladle furnace slag (LFS), pyrolysis carbon black (PCB) as SCM in cement-based composites, offering a sustainable approach towards the green atmosphere. The study experimentally compares the performance of 13 different mortar mixes, substituting the ordinary Portland cement (OPC) with varying weight percentages (0% as control, 5%, 10%, 15%, and 20%) of each waste. Including chemical composition analysis of OPC and alternative binders; several physical properties, mechanical properties, particularly compressive strength, flexural capacity, strength at elevated temperatures, strength activity index (SAI), durability characteristics are performed on afore-mentioned mortar mixes. Moreover, the failure pattern, microstructure, and presence of chemical substances in the composites are examined. This investigation also highlights the strength-CO2 emission measure and economic viability of the material considering waste processing charges. The results satisfy ASTM standard strength requirements for all 13 mixes, a minimum 75% SAI was achieved in all cases except 20% cement replacement level of PCB. Compared to the conventional control mix, 5% RCD blended mortar exhibited 9% higher compressive strength. In contrast, PCB showed a continuing decline in compressive strength, with a reduction up to 45% for 20% replacement level. Incorporating 10% slag as SCM, improved performance was obtained in terms of compressive strength (+7.9%), flexural strength (+11.7%), strength at 800 °C (+22%), strength-CO2 ratio (+15%), economy index (+9.1%) while compromising workability (−62.7%) and durability.

Recycling of MoSi2-based industrial solid wastes for the fabrication and high-temperature oxidation behavior of MoSi2–ZrSi2–SiC composite coating

To protect Nb substrate from oxidation at elevated temperatures and make better use of the industrial solid wastes, spent MoSi2 heating elements, ZrSi2 and SiC were applied as raw materials to prepare MoSi2 and MoSi2–ZrSi2–SiC coatings by Spark Plasma Sintering (SPS). After high-temperature sintering, cracks were found in a single MoSi2 coating while MoSi2–ZrSi2–SiC coating was crack-free without any defects by the CTE mismatch reduction. Diffusion layers formed on the substrate and it strengthened the bonding in the coating system with good metallurgical combination. The oxide scale of the composite coatings possessed compact and crack-free morphologies with fractional consumption after oxidation at 1500 °C. Circular Mo5Si3 phases that possessed pores and cracks generated in the silica layer of MoSi2 coating at 1700 °C while MoSi2–ZrSi2–SiC composite coating still kept crack-free oxide scale, thus showing excellent 1700 °C anti-oxidation properties.

Assessing the Viability of Industrial Waste Recycling in RAP-Incorporated Geopolymer Concrete Pavements: An Investigation into Performance Correlations

Assessing the Viability of Industrial Waste Recycling in RAP-Incorporated Geopolymer Concrete Pavements: An Investigation into Performance Correlations

Recycling of yeast multifunctional autolysates and extracts in the food industry

Recycling of industrial waste is one of the most crucial problems for the food industry. The forces of modern researchers are focused on solving this problem and using the biopotential of spent resources. Residual yeast from fermentation industries, in particular brewing, is of particular interest among the variety of food production waste. This is due to the extremely rich chemical composition of the yeast cell, and the possibility of obtaining a wide range of ingredients that exhibit both biological activity and technologically significant properties. Spent brewer's yeast is rich in proteins and carbohydrates, as well as vitamins B and minerals. The protein fraction, which accounts for 45–60% by dry weight (dw), contains all essential amino acids in sufficient quantities, which allows considering this secondary material resource an excellent source of protein with high biological value and a well-balanced AA profile. The carbohydrate fraction, comprising approximately 40% by dw, consists of intracellular carbohydrates (such as simple sugars and glycogen) as well as cell wall polysaccharides (such as β-glucan and α-mannan). Special emphasis is placed on the cell wall components due to their significant multidirectional biological activity and technologically important properties. Thus, β-glucan and α-mannan, along with emulsifying, sorbing and stabilizing properties, exhibit antioxidant and antimicrobial activity, immunomodulatory and prebiotic properties. This review presents an analysis of yeast autolysates and extracts sources as well as the influence of cultivation conditions and production methods on their chemical composition.

Challenges for Future Robotic Sorters of Mixed Industrial Waste: A Survey

To achieve recycling of mixed industrial waste toward an advanced sustainable society, waste sorting automation through robots is crucial and urgent. For this purpose, a robot is required to recognize the category, shape, pose, and condition of different waste items and manipulate them according to the category to be sorted. This survey considers three potential difficulties in the sorting automation: 1) End-effector: to robustly grasp and manipulate different waste items with dirt and deformations; 2) Sensor: to recognize the category, shape, and pose of existing objects to be manipulated and the wet and dirty conditions of their surfaces; and 3) Planner: to generate feasible and efficient sequences and trajectories. This survey includes 76 references to studies related to automatic waste sorting and 159 references to worldwide waste recycling attempts. This pioneering investigation reveals the possibility and limitations of conventional systems; thus, providing insights on open issues and potential technologies to achieve a robot-incorporated sorter for the chaotic mixed waste is one of its contributions. This paper further presents a system design policy for readers and discusses future advanced sorters, thereby contributing to the field of robotics and automation. <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Note to Practitioners</i> —Most automated sorting systems operate for limited target waste items. This study is motivated by the automation of mixed industrial waste treatment facilities using advanced robotic sorters. Emerging advances and increasing functionalities of robot system components will widen system applicability and increase use cases in the chaotic mixed industrial waste domain. This paper surveys the research conducted to date, discusses open issues and potential approaches, and presents user guides that provide practitioners with a system design policy. The user guides created according to the strengths and weaknesses of each system configuration provide future researchers and developers with a useful a priori design policy that has been thus far validated on efficiency, quality, productivity, and reliability. A question-and-answer style guide and a sorting-target-aware previous study reference list allows users to find the desired system configuration, including the investigated components according to their purpose.

Paint sludge derived activated carbon encapsulating with cobalt nanoparticles for non-radical activation of peroxymonosulfate

Industrial solid waste management and recycling are important to environmental sustainability. In this study, cobalt (Co) nanoparticles encapsulated in paint sludge-derived activated carbon (AC) were fabricated. The Co-AC possessed high conductivity, magnetic properties and abundant metal oxide impurities (TiAlSiOx), which was applied as multifunctional catalyst for peroxymonosulfate (PMS) activation. Compared to pure AC, the Co-AC exhibited significant enhanced performance for degradation of tetracycline hydrochloride (TCH) via PMS activation. Mechanism studies by in situ Raman spectroscopy, Fourier infrared spectroscopy, electrochemical analysis and electron paramagnetic resonance suggested that surface-bonded PMS (PMS*) and singlet oxygen (1O2) are the dominant reactive species for TCH oxidation. The non-radical species can efficiently oxidize electron-rich pollutants with high efficiency, which minimized the consumption of PMS and the catalyst. The removal percentages of TCH reached 97 % within 5 min and ∼ 99 % within 15 min in the Co-AC/PMS system. The Co active sites facilitated PMS adsorption to form the PMS* and the TiAlSiOx impurities provided abundant oxygen vacancy for generation of the 1O2. In addition, the Co-AC/PMS system achieved high efficiency and stability for oxidation of the target pollutants over a long-term continuous operation. This work not only offers a cost-effective approach for recycling industrial waste but also provides new insights into the application of waste-derived catalyst for environmental remediation.

Structural and compositional diversity of biosurfactants produced by a novel strain of Sporosarcina luteola ME44 from oil reservoir.

The urealytically active microorganism Sporosarcina luteola induces the precipitation of metals, which has attracted attention in biomineralization, bioremediation, and industrial waste recycling. Herein, we report a novel biosurfactant-producing strain of S. luteola ME44 isolated from Chinese Oilfield. The structure, composition, and surface activity of the biosurfactants produced by S. luteola ME44 were investigated by using a combination of the high-performance liquid chromatography, time-of-flight mass spectrometry, and surface tensiometer. The biosurfactant extracted by strain ME44 was identified as surfactin with five variants and the yield was 1010±60mg⋅L-1 . This is the first report on the structural composition and surface activity of biosurfactants isolated from the S. luteola. It extended our knowledge about the role of the species S. luteola in the ecosystem of extreme natural environments such as oil reservoir. In addition, S. luteola ME44 showed bioprecipitation properties for metal ions Cd(II), Cu(II), Zn(II), and Ag(I), which indicated the application potential of S. luteola in the field of bioremediation.

THREE-DIMENSIONAL BROWNFIELDS: THE TRAGEDY OF THE MINING COMMUNITIES

The processes of active restructuring in the mining industry of many countries have entailed the physical closure of enterprises, accompanied by measures to mitigate their environmental and social impacts. Brownfields that emerged in districts with developed mining industries are predominantly perceived through a stereotypically flat, superficial, and narrowly literal lens. Adhering to such an approach is risky both in terms of ecology and in the aspect of economic losses incurred in territories with concentrated localization of mines. The article provides substantiation for the importance of perceiving brownfields within a threedimensional space, with due consideration given to geological deformations, dynamics of underground water and gas flows, and the potential of gravitational and geo-thermal energy. The authors propose interpreting brownfields as either oper ating or abandoned industrial sites with buildings and infrastructure facilities on the ground surface, as well as natural landscapes that are negatively affected by geological, hydrodynamic, and gas-dynamic processes characteristic of the disturbance of the subsoil due to underground or open-pit mining operations. The reuse and recycling of industrial waste accumulated within brownfields alone cannot ensure the survival of coal-mining towns. Similarly, depopulation cannot be halted solely through economic instruments. Thus, the strategy for the development of coal-mining towns should entail ‘enlightened’ restructuring in line with the ideas of ‘Smart Shrinking’.

Synergistic preparation of high-performance composite blast furnace slag powder from multiple industrial solid wastes: Performance regulation and optimization

Blast furnace slag (BFS) is commonly used as a substitute for cement clinker due to its hydration properties. However, the demand for BFS is outpacing the supply, and its price is rising steadily. Moreover, the significant accumulation of industrial waste with potential hydration properties poses a severe environmental threat. To address these challenges, this paper aimed to prepare high-performance composite blast furnace slag powder (CBFS) by incorporating red mud (RM), fly ash (FA), desulfurization gypsum (DG) and BFS, guided by the synergistic effects and the theory of medium-calcium systems. This paper reveals that the primary activation methods of the amorphous silicon-aluminum mineral phases in CBFS are alkali activation and sulfate activation. The optimal results demonstrate that the compressive strength of CBFS-cementitious material (50% CBFS + 50% cement) can reach 52.8 MPa, meeting the standards of Portland Cement PO 42.5. Additionally, RM, FA and DG account for 66% of CBFS and the hydration activity of CBFS is better than that of S95-grade BFS. Furthermore, the CBFS-cementitious material effectively immobilizes hazardous elements of the raw materials, and the leachate meets drinking water standards. The application of CBFS facilitates the recycling of industrial solid wastes, improves the quality of construction materials and reduces the construction industry's dependence on BFS.

Recycling of Coal Combustion Waste through Production of Foamed Geopolymers with Improved Strength

Recycling of industrial waste into useful materials is a crucial aim for achieving sustainable development in materials science. The use of production waste in the manufacture of construction materials contributes to improving the environmental situation and reducing the cost of the final product. This article examines the utilization of coal combustion waste recycled into foamed geopolymers and ways of enhancing their strength properties through the introduction of strengthening additives. Eight compositions of foamed geopolymers containing different strengthening additives were synthesized. Inorganic substances (CaO, MgO, ZnO, TiO2, Al2O3, SiC, and ZrO2) were chosen as strengthening additives that were introduced in an amount of 3% (over 100%). The physical and mechanical properties (density, compressive strength, porosity, and pore size distribution) of the obtained samples were studied and compared. Magnesium oxide MgO and aluminum oxide Al2O3 were chosen as the best strengthening additives. Magnesium oxide allows geopolymer materials with the lowest density to be obtained. Aluminum oxide can significantly increase the strength of geopolymers. The phase composition of the samples contains new crystalline phases in the form of α-alumina and periclase. The porous structure is homogeneous and meets the requirements for foamed thermal insulation materials. The strengthening effect of the chosen additives was verified using geopolymers based on different waste from Novocherkassk SDPP.

An intelligent design method for new binder material activated by solid wastes by integrating attention-based tree model and heuristic optimization algorithm

To promote the utilization of industrial solid waste, a new green binder system namely SCGF for sustainable concrete is developed, in which slag-fly ash is activated by soda residue-carbide slag. However, the mix design of the SCGF is challenging due to heavy workload and the lack of theoretical basis. The relationship between mix proportion and mechanical properties of SCGF needs to be accurately expressed. In this paper, an intelligent design method of SCGF is proposed by coupling the attention mechanism, machine learning and multi-objective heuristic optimization algorithm. After training with experimental data, the prediction performance of attention-based tree model is evaluated. Multiple Pareto optimal solutions can be obtained by the proposed intelligent mix proportion design method. The results show that attention-based tree models perform higher accuracy (accuracy > 95 %) and better measures than that of classical tree models. Compared the strength and cost of SCGF to cement mortar, the mix proportion designed in this study has obvious advantages in environmental protection and economy (>50 % cost saving). Therefore, the proposed method can provide a theoretical basis for the recycling and utilization of industrial solid wastes.

Comprehensive utilization of blast furnace slag, municipal sludge and kaolin clay in building brick manufacture: Crystalline transformation, morphology observation and property assessment

At present, the comprehensive utilization of bulk industrial solid waste has attracted wide attention. The recycling of industrial solid waste in building materials not only provides valuable insights for the management of solid waste, but also alleviates the over-exploitation of natural clay resources in the construction industry. In this study, municipal sludge (MS) and blast furnace slag (BFS) were incorporated into kaolin clay (KC) to synthesize sustainable composite bricks, and the sintering effects and engineering properties of bricks were adjusted by changing BFS dosages. The results indicated that the addition of BFS would promote liquid glassy phase production in bricks due to the higher content of alkali/alkaline-earth metal oxides, and the ingredient, viscosity and content of liquid glassy phases could also be regulated through varying the dosage of BFS (0-15%), thereby affecting the pore structure, particle arrangement/consolidation and performance of bricks. Among all synthesized bricks, the optimum dosages of BFS, MS and KC for satisfying the building standard thresholds were 10%, 40% and 50%, with corresponding linear shrinkage, porosity, density, water absorption, compressive and flexure strengths of 12.97%, 18.15%, 1.83 g/cm3, 0.82%, 15 MPa and 38 Mpa, respectively. Finally, mechanism analysis further demonstrated that the formation and evolution of liquid glassy phases were the key responsibility for adjusting the brick micromorphology and performance. Based on this study, using MS and BFS in brick manufacturing benefited the value-added utilization of industrial solid wastes, clean protection of environments and sustainable production of building materials, providing a reference for the process optimization and potential application of MS and BFS wastes in masonry construction.

Synergistic flame retardancy of piperazine pyrophosphate/magnesium hydroxide/fly ash cenospheres-doped rigid polyurethane foams

In order to explore rigid polyurethane foams (RPUFs) with excellent flame retardancy and mechanical properties, this study incorporates the ternary flame-retardant system of piperazine pyrophosphate (PAPP)/magnesium hydroxide (MH)/fly ash cenospheres (FAC) into RPUFs. The results show that doping 6 wt% FAC significantly improves the flame retardancy of the PAPP/MH/FAC-doped RPUFs. The peak heat release rate (p-HRR) decreases from 236.7 kW·m−2 to 127.2 kW·m−2, while the fire resistance index (FRI) increases from 1.00 to 5.34, and passes a vertical burning (UL-94) test V-0 rating. Meanwhile, the RPUFs possess an intact, compact, and robust non-flammable shielding layer due to the formation of the interpenetrating network structure and the physical accumulation of silicon carbon phosphorus residues. Moreover, the pyrolysis kinetics is modeled using the G(α) with reaction order n = 2, PAPP/MH/FAC-doped RPUFs make the pyrolysis activation energy Eα climb from 78.97 to 131.79 kJ·mol−1 at 237–340 °C, corresponding to the decomposition of PAPP and the excellent thermal stability of FAC. Furthermore, PAPP/MH/FAC-doped RPUFs enhance compressive strength while improving flame retardancy and exhibit excellent formaldehyde adsorption performance (adsorption capacity is 64 %). Therefore, this study explores a novel PAPP/MH/FAC-doped RPUFs, promoting the recycling of industrial coal-fired waste and the development of high-performance building materials.

Influence of Incorporating PVC Waste on the Mechanical Properties of Cement Mortar

Currently, recycling of industrial wastes to reduce the environmental impact is the major concerns of researchers. Polyvinyl chloride (PVC) is one of the waste materials worldwide, with considerable impacts on environmental. Recycling PVC wastes in the concrete or mortar industry is one of the adopted ways to decrease such impact. The purpose of this paper is the reuse of PVC waste deriving from the workshops manufactured doors and windows which made of PVC material. The waste of polyvinyl chloride was collected from one of the factories located in AL-Khoms, then the waste was sieved, the sample that passed through Sieve No.4 and retained on sieve No.10 was taken. The PVC waste proportions of (0.06 ˛ 0.08 ˛ 0.1) by weight of cement was added to the mix mortar. The tests carried out during this study were; air content of fresh cement mortar, flow table, dry density of hardened cement mortar, flexural and compression, free shrinkage and finally ultrasound pulse velocity. The results obtained showed a significant improvement in the sound insulation and a decrease in the dry density of the mortar. While the compressive and flexural strength results were slightly lower compared to the standard mortar. In addition, a decrease in the values of flow, free shrinkage and air content was observed with an increase in the PVC content. Nevertheless, the mortar obtained contributes to the conservation of natural resources and maintains the mechanical properties of the cement mortar in structural applications.

Wet removal of elemental mercury by acid-assisted electrochemical oxidation method

As a global pollutant, mercury emission is increasingly restricted in recent years. It is urgent to explore a new and efficient mercury removal technology for coal-fired power plants. A new acid-assisted electrochemical oxidation (AEO) technique for mercury removal was proposed using platinum plate as cathode and fluorine-doped tin dioxide (FTO) glass as anode. The effects of acid type, acid concentration, applied direct current (DC) voltage, electrolyte type, SO2, NO and O2 on the Hg0 removal efficiency were carried out. The results indicated that the mercury removal efficiency increased with the increase of DC voltage and nitric acid concentration. When the concentration of nitric acid increased to 0.15 mol/L, the mercury removal efficiency remained unchanged. SO2 and NO inhibited the removal of Hg0 in AEO system, but the inhibition was reversible. Compared with the mercury removal efficiency under single experimental conditions, the mercury removal efficiency of electrochemical oxidation can reach 96% under the experimental conditions of 0.1 mol/L nitric acid and 4V DC voltage, suggesting that the synergistic effect of nitric acid and DC voltage plays a key role. According to the experimental results, the mechanism of Hg0 removal in AEO system was analyzed. At the anode, Hg0 was oxidized by hydroxyl radical (.OH) generated by the oxidation reaction on the anode surface. At the cathode, dissolved oxygen or O2 adsorbed on the surface of Pt is reduced to form anionic superoxide radicals (.O−2). Moreover, parts of .O−2 would produce .OH with the aid of electron at acidic condition. Free radicals capture experiments showed that .O−2 and .OH were the main active substances for the removal of Hg0 by acid-assisted electrochemical method. The research is helpful for the development of effective electrochemical techniques for industrial mercury removal and recycling of industrial acid waste.

Recycling of cathode ray tubes and stone sludge for the synthesis of Al-MCM-41 grafted amine functional group and environmental humidity control material applications

There is a growing need for economical methods by which to reuse industrial waste. This paper reports on the recycling of industrial waste in the preparation of amine functionalized mesoporous molecular sieves (Al-MCM-41), for use as a building material applicable to the energy-free regulation of indoor humidity. The preparation of amine functionalized Al-MCM-41 for experiments involved combining stone sludge, cathode ray tube panel waste glass, an alkali agent (sodium hydroxide), and cetyltrimethylammonium bromide with aminopropyltriethoxysilane in various proportions. The water vapor adsorption of amine functionalized Al-MCM-41 (42.85 g/m2) far exceeded of amine functionalized Al-MCM-41 without surface grafting (28.64 g/m2). Al-MCM-41 with 2.5 vol% amine functional groups achieved the highest 24-h water vapor adsorption performance in compliance with JIS A 1470 standards. This research provides an economical approach to the recovery and recycling of industrial waste that is rich in silicon and aluminum.

Characterization and recycling of raw fly ash derived through stems of Sesamum indicum as a proficient adsorbent for chlorazol black E from wastewater

Coal fly ash (CFA) is an anthropogenic industrial byproduct that is expected to increase exponentially to fulfill the needs of energy using coal and agro-waste as a cheap fuel. The disposal of this classified human carcinogen is a major concern in developing and underdeveloped economies due to lack of resources. Recycling and value addition of industrial waste, coherence with sustainable development goals is a viable solution. Zeolitization of coal fly ash is an ideal approach for recycling this waste into superior products to be used in a variety of industrial applications. This study was aimed to recycle CFA to useful zeolites using ultrasound assisted hydrothermal process. Sesamum indicum plant stems based fly ash (rFA) was found to belong to class “F" and has very low moisture and carbon contents. To investigate the morphology and elemental composition of rFA and UHSZ, SEM/EDX was used along with XRD, FTIR and Raman spectroscopy which confirmed the existence of quartz, mullite and anhydrite. SEM/EDX results revealed the presence of Al, Si, S, K, Sb, Mg and Ta in raw ash. Adsorption studies of both rFA and synthesized zeolite(UHSZ) were conducted to determine the quintessential parameters of pH, time, initial dose of adsorbent for optimum results. Fabricated zeolites (2 ​g/100 ​mL) from raw fly ash removed 90–98% of chlorazol black E (DB38) from 100 ​mg/L solution within 40 ​min at pH ​≈ ​7. Both Langmuir and Freundlich isotherms gave best fit, which validated that the adsorption of DB38 to UHSZ was a blended process rather than a simple monolayer adsorption mechanism. Pseudo 1st-order and 2nd-order kinetic models were adopted to fit the obtained kinetic data. The pseudo 2nd-order kinetic model was found to be most related.