Novel Approach For Recovery Research Articles

Utilization of the easy electron-losing capacity of dog fur waste for green energy devices and self-powered smart pet care systems

The present global energy shortage and climate crisis can be addressed by embracing recycling, reuse, and recovery; for example, this can be achieved by methodically utilizing the problematic wastes for energy harvesting. This research describes a novel approach for recovery and reutilization of waste material by incorporating dog fur waste into a triboelectric energy harvester; this was accomplished via a simple, inexpensive, and eco-friendly chemical processing to turn this problematic waste into a high-performance tribolayer. Due to the complications of operating practical devices with dog fur in its natural form, the dog fur waste was transformed for the first time into a uniform thin-film-based high-performance positive tribolayer. The optimization of the fabrication of the dog fur film featured hexagonal pyramid nanostructures, and a novel tribopair was selected and consisted of the dog fur-based film and a Teflon film; these films have very large differences in electron affinities. Based on this optimization and selection, we achieved an outstanding output voltage, current, and power density of 2021.46 V, 109.84 μA and 24,669.957 μWcm−2, respectively, along with appreciable mechanical stability during continuous operation up to 10,000 cycles. Our research demonstrates the potential for integration of green electronics and self-powered human-pet interaction systems while providing a sustainable approach to a circular bioeconomy.

A novel approach for recovery of iron from copper slag using calcium salts.

Copper slag is not only a waste but it has many valuable and recoverable metals present in it such as iron. Therefore,this study focuses on the utilization of waste materials i.e.,copper slag and tire char for iron recovery. Four calcium salts, i.e., CaCO3, Ca(OH)2, CaCl2, and CaSO4, with different dosages, reduction temperature, reduction time, and atmospheric conditions were investigated in order to find best reaction mechanism for iron recovery. Among these salts, the optimum conditions were determined: using CaCO3 under 0.384 of CaO/SiO2 molar ratio in a 60-min reduction period at 1473.15K temperature, that gives 91.14% iron recovery. Both FESEM-EDS data and chemical titration showed more than 70% of the highest iron grade in the recovered product. The analysis results indicate that main impurity in the whole procedure was carbon from coal char that reduces the iron grade. This research not only provides a novel way to recover iron from copper slag, but also provides a future direction to handle copper slag and tire char waste materials.

From Waste to Wealth: Novel Approach for Recovery of Metals from Spent Lithium-Ion Batteries Using Biological Waste

From Waste to Wealth: Novel Approach for Recovery of Metals from Spent Lithium-Ion Batteries Using Biological Waste

Novel approach for recovery of palladium in spent catalyst from automobile by a capture technology of eutectic copper

Abstract In worldwide, more than half of palladium is used to produce exhaust catalysts in the automotive industry. However, the recycling of palladium is a great challenge due to its low content and chemical inertness. A novel approach for recovery of palladium in spent catalyst material from automobile by a capture process of eutectic copper was proposed. In the capture process, copper is used as capture agent. The palladium is concentrated and entered the alloy phase under a certain temperature. Because the different density of the smelting slag and alloy, they are layered to realize the separation of the metals. The results were summarized as follows: (i) palladium in the spent catalyst material was captured by copper with 97% of recovery rate of Pd under optimal condition; (ii) the palladium atoms replaced to copper in Cu crystal to form Cu–Pd alloy by analysis of EDS, XPS and first principles calculation; (iii) the carrier of cordierite from spent catalyst material achieved glass transition and prepared the glass ceramics after the capture; (iv) a thermodynamic mechanism of the capture process of copper was proposed. Firstly, under molten state of the copper phase and the slag phase, palladium can be transferred from the slag phase to the copper phase when ΔEsurface = 2πrΔS1 (σpalladium-copper-σpalladium-slag-σslag-copper cosα)

A novel approach for recovery of manganese from on-site manganese-bearing wastewater

Acid leaching of rhodochrosite will generate electrolytic manganese residue together with emission of carbon dioxide (CO2). Wastewater containing highly concentrated manganese is being generated when treating electrolytic manganese residue. Although carbonate precipitation has been identified as an effective process for manganese removal, this conventional approach is limited by heavy use of alkaline solution and the obtained MnCO3 precipitates have low purity. In this study, an electrolytic manganese plant in Guangxi, China was selected as the study site. CO2 generated from flue gases was carefully chosen as the potential reagent for the recovery of manganese from wastewater. The effects of operational modes including batch mode, batch mode with external recirculation, continuous mode and continuous mode with external recirculation on the performance of wastewater treatment were systematically investigated in pilot scale, and the obtained precipitates were characterized by X-ray powder diffraction (XRD), scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDS) and the thermal gravity-differential thermal analysis (TG-DTA). It was found that batch mode with external recirculation is optimal as over 99.99% of Mn2+ can be selectively recovered from Ca2+, Mg2+ and Mn2+-containing wastewater by bubbling with CO2, and the obtained MnCO3 precipitates met the industrial standard in China (grade I). The pH value of the effluent is 6.6 and the concentration of Mn2+ is 1.0 mg L−1, which can be recycled within this system. The present study provides a sustainable technique to solve the problems of treating industrial wastewater containing heavy metals.

A novel approach for recovery of metals from waste printed circuit boards and simultaneous removal of iron from steel pickling waste liquor by two-step hydrometallurgical method

Waste printed circuit boards (WPCBs) and steel pickling waste liquor (SPWL) have received extensive attention in recent years because of its harmfulness and resource. In this work, two-step leaching process was carried out by using SPWL as the leaching agent. A series of continuously domesticated bacteria were used for bioleaching and the bacterial strain was identified as Acidithiobacillus ferrooxidans (A. ferrooxidans) by 16S rDNA gene sequence analysis. The vast majority of the metals in WPCBs were recovered by two-step leaching, such as Cu, Pb, Zn, Sn, Al, Ni. Meanwhile, a large amount of iron was removed from SPWL, which greatly reduces the burden of the subsequent treatment. Pulp density and pH were optimized to achieve maximum recovery of copper and simultaneous removal of iron in bioleaching. It was found that the optimum conditions were pulp density 60 g/L and pH 0.5–1.0. Nearly 100% of copper was recovered and 51.94% of iron was removed under optimum conditions. The kinetic experiments showed that the rate of copper leaching was controlled by external diffusion rather than internal diffusion, because the acidic environment of the leachate prevented the formation of the precipitate and maintained it in a smaller size.

Separation and Recovery of Iron and Rare Earth from Bayan Obo Tailings by Magnetizing Roasting and (NH4)2SO4 Activation Roasting

A novel approach for recovery of iron and rare earth elements (REEs) from Bayan Obo tailings of Baotou, China, was developed by combining magnetizing roasting, magnetic separation, (NH4)2SO4 activation roasting, and water leaching. Thermodynamic analysis of carbothermal reduction was conducted to determine the temperature of magnetizing roasting, and it agreed well with the experimental results. The maximum recovery of Fe reached 77.8% at 600 °C, and the grade of total Fe in the magnetic concentrate was 56.3 wt. %. An innovative approach, using water to leach REEs after (NH4)2SO4 activation roasting, was used to extract REEs from magnetic separation tailings. The main influence factors of the leaching recovery during (NH4)2SO4 activation roasting, were investigated with the mass ratio of (NH4)2SO4 to magnetic separation tailings, roasting temperature and roasting time. The leaching recoveries of La, Ce and Nd reached 83.12%, 76.64% and 77.35%, respectively, under the optimized conditions: a mass ratio of 6:1, a roasting temperature of 400 °C and a roasting time of 80 min. Furthermore, the phase composition and reaction process during the (NH4)2SO4 activation roasting were analyzed with X-ray diffraction (XRD), energy dispersive X-ray spectroscopy & scanning electron microscopy (EDS-SEM) and thermogravimetry & differential scanning calorimetry (TG-DSC), and the leaching solution and leaching residue were also characterized.

A novel dictionary-based approach for missing sample recovery of signals in manifold

Recovery of signal with randomly positioned missing samples is a difficult or impossible task. The aim of this paper is to accurately recover missing samples if prior information on domain of sparsity is known. This paper proposes a novel approach for recovery of signals lying in low-dimensional sub-manifold, embedded in high-dimensional signal space and heavily corrupted by arbitrarily positioned missing samples. The proposed simple and efficient algorithm is based on global manifold model and can recover the corrupted signal from the limited available samples without affecting the remaining samples. The proposed method is applicable to any type of data and can be extensively used in a wide variety of data processing techniques. Experimental results prove that the proposed method outperforms the counterparts without much computational complexity.

A novel approach for recovery of nickel and iron from nickel laterite ore

In recent years, there has been an increasing focus on the utilization of low-grade nickel laterite ore. In this study, the technology for efficient utilization of nickel laterite ore was investigated. The results indicate that the experimental sample is a kind of strong acidic ferric oxide ore containing nickel, which tends to appear as a complex with argillaceous mineral. The results indicate that the ultrasonic field has a significant effect on the leaching rates of nickel and iron.Optimum leaching conditions were found as follows: size of mineral particles: 95% less than 0.074 mm; leaching temperature: 80 °C; concentration of sulfuric acid: 190 g/L; liquid-solid ratio: 5:1; leaching time: 2 h; stirring speed: 400 rpm. Under these conditions, the leaching rates of nickel and iron reach 98.35% and 91.28% with the ultrasonic field exertion working 4 min every 5 min. In contrast, the leaching rates of nickel and iron are 78.84% and 80.26% after 2 h without the ultrasonic field. A product with Fe grade of 63.56% could be obtained by precipitation and roasting, the total recovery of nickel and iron reaching 95.62% and 86.50%, respectively. The reasonable recovery technology of nickel laterite ore containing a high content of limonite minerals was determined by this work.

Reconstructing effective phase connectivity of oscillator networks from observations

We present a novel approach for recovery of the directional connectivity of a small oscillator network by means of the phase dynamics reconstruction from multivariate time series data. The main idea is to use a triplet analysis instead of the traditional pairwise one. Our technique reveals an effective phase connectivity which is generally not equivalent to a structural one. We demonstrate that by comparing the coupling functions from all possible triplets of oscillators, we are able to achieve in the reconstruction a good separation between existing and non-existing connections, and thus reliably reproduce the network structure.

Facile recovery of acetic acid from waste acids of electronic industry via a partial neutralization pretreatment (PNP) – Distillation strategy

In recent years, attention on treatment of industrial waste acids has been increasing considerably due to enforcement of the environmental regulations as well as economical considerations about the waste acids. In this paper, a novel approach for recovery of acetic acid (HAc) from electronic industrial waste acids, containing about 58wt.% of HAc, 39wt.% of nitric acid (HNO3), 3wt.% of phosphoric acid (H3PO4), and small amount of hydrochloride acid (HCl) and hydrofluoride acid (HF), was developed using partial neutralization pretreatment (PNP)-distillation strategy. The effects of distillation time, types of alkali for neutralization and oil bath temperature on recovery of HAc were systematically studied. It was found that HAc can be efficiently recovered from the waste acids with a yield of 94.3% (purity 99.4%) under optimal conditions. The treatment scheme for HAc recovery from waste acids is featured by feasibility, reproducibility and massive productivity.

A novel approach for recovery of rare earths and niobium from Bayan Obo tailings

It is difficult to economically recover rare earths (RE) and niobium (Nb) from Bayan Obo tailings by the existing metallurgical processes. In this study, a novel hydrometallurgy process was employed for separating and recovering RE and Nb from Bayan Obo tailings. Firstly, by sulfating roasting at 250°C and subsequent leaching at 60°C, the RE and Nb present in the polymetallic minerals can be efficiently extracted into the leach solution. Secondly, after the reduction of Ti4+ and Fe3+ ions (to Ti3+ and Fe2+ ions) with iron powders followed by hydrolysis at pH 2.01, the Nb can be efficiently precipitated from the leach solution. The impurities present in the precipitated product can then be removed by treating with NH3⋅H2O–H2C2O4 system at pH 4.50. Thirdly, the RE can be efficiently precipitated at pH 7.15 from the filtrate of above hydrolysis reaction mixture. Finally, the impurities present in the crude RE can be removed by oxalate co-precipitation method. The yield of RE and Nb in this novel process reaches up to 90% and 78%, respectively. Both the Nb (60.67wt% Nb2O5) and RE products (>88.65wt% RExOy) have high application value.