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Air separation processes are time‐consuming and energy‐intensive. Most of the energy used in air separation unit (ASU) is used for air compression. During the air compression process, some energy is lost, which is converted into waste heat. This wasted energy is used to warm liquefied natural gas (LNG). At some point, LNG ships will dock at an LNG regasification facility. Here, LNG is converted back to gas and supplied to the distribution and transmission systems. During the regasification process, cryogenic LNG has a huge opportunity for cold energy recovery. An innovative air separation process that is integrated with the cold utilization of LNG is presented in this study along with a thorough conceptual design and analysis. The results of this study show that producing high‐purity oxygen and nitrogen, respectively, requires 0.28 kWh kg−1 and 0.06 kWh kg−1 of specific energies. Prior to integration with cold utilization of natural gas, 25 141.6 kW is needed for air compression. However, following integration, 10 554.6 kW of energy is needed, resulting in a 58.01 % energy savings. Exergy destruction as well as efficiency have been calculated for the primary components of the system. Sensitivity analysis is carried out to examine the effects of LNG streams on important parameters. In conclusion, a cryogenic ASU is integrated with an LNG‐direct expansion cycle‐organic Rankine cycle power cycle to supply the necessary power for operation and reduce extraneous power inputs. Overall, this integrated approach increases efficiency, lowers costs, benefits the environment, allows for flexibility and adaptability, and raises system dependability. [ABSTRACT FROM AUTHOR]

The effectiveness of low‐cost fly ash geopolymer (FAGP) adsorbents synthesized from biomass fly ash in lead removal from aqueous solution was studied. The synthesized FAGP was characterized by the Brunauer‐Emmett‐Teller method and energy dispersive spectroscopy. The adsorption experiments were performed in batch mode under various conditions, and the maximum removal efficiency and uptake were found at an optimum time of 120 min and pH 5. Adsorption isotherm studies confirmed that lead removal is best fitted by both Langmuir and Freundlich isotherms. A kinetic analysis showed that pseudo‐second‐order kinetics governs lead adsorption. Lead adsorption was determined to be an endothermic, spontaneous process through thermodynamic analysis. [ABSTRACT FROM AUTHOR]

This work investigated the potentiality of Hypnea musciformis algae as a biosorbent for the removal of indigo carmine dye from synthetic solution. The sorption experiments were performed in batch mode under different parametric conditions like pH, contact time, the average particle size of biosorbent and its dosage, dye solution initial concentration, and temperature. The experimental results confirmed the optimum contact time is at least 25 min and favorable pH of 5 for the biosorption of carmine dye. Langmuir, Freundlich, and Temkin isotherms have been used to test the equilibrium data and found the best fit with the Freundlich isotherm with a regression coefficient (R2) of 0.992 followed by Langmuir (R2 = 0.979) and Temkin isotherm (R2 = 0.94). The analysis of kinetic data revealed Pseudo first order as the best fit. The thermodynamic parameter evaluated confirmed the endothermic nature of indigo carmine dye biosorption process. [ABSTRACT FROM AUTHOR]

Considering the toxicity, the removal of heavy metals from the liquid effluent is of great significance. This article addresses the impact of the adsorbent bed height and flowrate on the adsorption performance and breakthrough curves in column studies. To explore the potential of Liagora viscida biosorbent, adsorption experiments were conducted in a packed column at various bed heights in the range of 2 to 6 cm and flow rates in the range of 10 to 20 ml/min. The maximum uptake of 53.90 mg/g has been achieved at the flow rate of 20 ml/min for an initial metal solution concentration of 20 ppm and pH and bed height of 6 and 2 cm, respectively. In the current study, the breakthrough (tb) and exhaust times (ts) correspond to 0.1 and 0.9, respectively. To predict the breakthrough characteristics, the experimental data were tested using Bohart‐Adam (B‐A), Bed Depth Service Time (BDST), Thomas, and Yoon‐Nelson (Y‐N) models. The experimental results confirmed that all three models except the Bohart‐Adams model were suitable for the experimental data with a good correlation coefficient. [ABSTRACT FROM AUTHOR]

The present article addresses the effect of various parameters on batch biosorption of nickel using an inexpensive Liagora viscida algae as a biosorbent. The experimental studies revealed that for an initial metal solution concentration of 20–200 ppm, the equilibrium is achieved after 50 min and the maximum sorption at a pH of 5. Isotherms such as Temkin, Freundlich, and Langmuir were examined. The data are well suitable by using the Langmuir isotherm with a sorption uptake of 22.77 mg/g, confirming that L. viscida can be considered as a low‐cost biosorbent. The dynamic experimental data were represented well by pseudo‐first‐order kinetics. The thermodynamic study revealed that the biosorption of nickel on to L. viscida was endothermic and spontaneous. [ABSTRACT FROM AUTHOR]

The article elaborates upon the optimality of electroplating and surfactant coupled electroplating based chromium oxide barriers on the process and product characterization variables of Pd electroless plating during dense Pd composite membranes fabrication. Porous stainless steel discs with 100 nm pore size were deployed to fabricate Pd composite membranes on chromium oxide diffusion barriers prepared with electroplating (7.8 and 20 µm thickness) and surfactant assisted electroplating (7.1 and 12.5 µm thickness). These diffusion barrier films were obtained by subsequent oxidation of chrome plated films at 700 °C. Eventually, palladium films were achieved using rate enhanced Pd electroless plating associated with coupled surfactant and sonication under dropwise addition mode of reducing agent. The surfactant inclusion during chrome plating enabled higher Pd metal film thickness and plating rates but could not provide better pore densification characteristics of dense Pd-chromia-PSS membranes. [ABSTRACT FROM AUTHOR]

This article addresses the effect of varying palladium solution concentration (0.005–0.015 mol/L) on the cost-effective fabrication of dense palladium composite membranes. Laboratory fabricated clay (kaolin) based ceramic disc were used as substrate along with a modified electroless plating technique consisting of a coupled effect of ultrasound and surfactant. Further to increase the efficacy of the process controlled addition of reducing agent was opted for all baths. It was analyzed that the optimal concentration that provided higher plating efficiencies (95.9%), higher transport efficiency (41.3%), higher plating rates (1.5 × 10−4 mol/m2 · s), minimal total plating time (10.5 h), and maximum pore densification (99.7%) corresponds to 0.01 mol/L. [ABSTRACT FROM AUTHOR]

Emphasizing upon a process–product combinatorial perspective, this article addresses the role of rate enhanced electroless plating baths for the fabrication of dense Pd/porous stainless steel composite membranes. Adopting phasewise contacting pattern of the reducing agent, plating experiments have been carried out with variegated Pd electroless plating baths at a palladium solution concentration of 0.005 M with a loading ratio of 203 cm2/L for the plating time of 2–6 h. Amongst all processes, surfactant and sonication coupled electroless plating baths provided optimal combinations of combinatorial plating process characteristics for dense Pd composite membrane fabrication. [ABSTRACT FROM AUTHOR]

This work addresses the role of chromia diffusion barrier on the combinatorial plating characteristics of Pd plating baths during fabrication of dense Pd/Cr2O3/porous stainless steel (PSS) composite membranes and is compared with those obtained during fabrication of Pd/PSS membranes. Cr2O3was deposited by electroplating technique followed with oxidation at 700°C and Pd films were deposited using a novel Pd electroless plating process that provides optimal performance. Apart from providing similar process characteristics, the Pd/Cr2O3/PSS membrane provided 15.2% lower Pd film thickness in comparison with Pd/PSS membrane for similar pore densification values. [ABSTRACT FROM AUTHOR]

This work addresses the preparation and characterization of inexpensive adsorbents for the removal of Ni (II) from aqueous solutions. Activated carbon based adsorbents have been prepared from plant based biomass resources, namely Pineapple stem (Ananas Comosus) and Bamboo Stem (Bambuseae). Adopting phosphoric acid and heat treatment techniques, it has been observed that the bamboo stem activated charcoal (BSAC) and pineapple stem (PS) adsorbents had a BET surface area of 116 and 11.47 m2/g, respectively. FTIR analysis indicated that various surface functional groups (such as C ≡ N stretching, stretching vibration of C = O, –CH3wagging and C–O stretching vibration) contribute towards Ni (II) adsorption. Batch mode adsorption experiments were conducted for these adsorbents in the range of 50–300 mg/L Ni (II) solution concentration, 2–10 pH, 15–300 min. contact time, and 0.02–0.1 g/50 mL dosage. The BSAC adsorbent has been characterized with a metal uptake and %removal of 121.72 mg/g and 92.47, respectively, which corresponds to 45% higher metal uptake than corresponding bamboo based adsorbents presented in the literature. Further experimentation with BSAC enabled to achieve activated charcoal with surface area values similar to that of the commercial activated carbon adsorbent. The bamboo adsorbent has also been evaluated to perform similar to the commercial activated carbon for the removal and recovery of Pd (II) from synthetic electroless plating solutions. Also, a conceptual cost analysis indicated and affirmed towards the potential of the BSAC adsorbents for waste water treatment applications. [ABSTRACT FROM AUTHOR]

Thisarticle presents the effects of the concentration and loadingratios of a cationic surfactant (CTAB) on the performance characteristicsof sonication-induced electroless plating baths for the fabricationof dense palladium composite membranes. The plating experiments wereconducted with dropwise addition of reducing agent at loading ratiosof 203 and 407 cm2/L, a palladium solution concentrationof 0.005 M, and surfactant solution concentrations of 1–4 CMC.A plating bath consisting of 0.005 M Pd with a surfactant concentrationof 2 CMC at a loading ratio of 203 cm2/L provided a 100%dense palladium composite membrane after 8 h of sequential platingwith a Pd film thickness of 11.16 μm and a plating efficiencyof 96%. The identified process can provide dense Pd/PSS compositemembranes at a fabrication cost of 13.27 $/cm2, which is60% more cost-effective than the best-known SIEP process. [ABSTRACT FROM AUTHOR]

Developing effective optimization models to improve pipeline network profitability in oil and gas supply chains is one of the most promising research areas in this industry. Because of the substantial advantages natural gas networks' operations have realized, this industry has become more competitive and eager to develop robust supply optimization decision models. However, although several models and techniques have been developed to reduce natural gas consumption, only very few studies have focused on comparing the performance of these models and the implications of the distinct optimization performances. Consequently, the generalizability of the research in the area is still problematic, representing a research area not sufficiently explored. Taking this into account, this paper compares the fuel consumption values in a French gas pipeline by analyzing the Genetic algorithms (GA), Generalized reduced gradient (GRG), and Ant colony optimization (ACO) models. Overall, our findings show significant differences in gas consumption when the ACO and GA are compared with the GRG technique. Furthermore, the findings indicate that ACOs are competitive with GA and GRG in computational efficiency in finding near-global optimized solutions. The article can assist decision-makers and policymakers in discovering the most profitable operational parameters to minimize gas consumption and increase the profitability of natural gas networks. • An optimization model to reduce gas consumption in compressor stations was tested. • We compare the performance of optimization methods to optimize the pipeline grid. • ACO is competitive with GA and GRG in finding the optimized solution. • The optimized scheme may reduce energy consumption by 2.7–8.1%. • The study offer insights for decision-makers, scholars and governments. [ABSTRACT FROM AUTHOR]