• Nuclear Engineering and Technology
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• v.47 no.5
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• pp.588-595
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• 2015

This study presents an effective method for additional recovery of residual actinides in liquid electrodes after the electrowinning process of pyroprocessing. The major distinctive feature of this method is a reactor with multiple reaction cells separated by partition walls in order to improve the recovery yield, thereby using the interelement difference in diffusion coefficients within the liquid electrode and controlling the selectivity and purity of element recovery. Through an example of numerical simulation of the diffusion scenarios of individual elements, we verified that the proposed method could effectively separate the actinides (U and Pu) and rare-earth elements contained in liquid cadmium. We performed a five-step consecutive recovery process using a simplified conceptual reaction cell and recovered 58% of the initial amount of actinides (U + Pu) in high purity (${\geq}99%$).

• Nuclear Engineering and Technology
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• v.54 no.10
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• pp.3957-3961
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• 2022

Deposition behaviors of Sr and Cs in various liquid cathodes, such as Zn, Bi, Cd, and Pb, were examined to evaluate their recovery from LiCl-KCl eutectic salt. Cations in the salt were deposited on the liquid cathode, exhibiting potential of -1.8 to -2.1 V (vs. Ag/AgCl). Zn cathode had successful deposition of Sr and exhibited the highest recovery efficiency, up to 55%. Meanwhile, the other liquid cathodes showed low current efficiencies, below 18%, indicating LiCl-KCl salt decomposition. Sr was recovered from the Zn cathode as irregular rectangular SrZn₁₃ particles. A negligible amount of Cs was deposited on the entire liquid cathode, indicating that Cs was hardly deposited on liquid cathodes. Based on these results, we propose that liquid Zn cathode can be used for cleaning Sr in LiCl-KCl salt.

• Korean Chemical Engineering Research
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• v.54 no.1
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• pp.135-139
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• 2016

We developed a liquid-liquid extraction method using an inorganic salt to dramatically improve the recovery efficiency of the anticancer agent paclitaxel from plant cell cultures. As a result of liquid-liquid extraction using a diverse types of inorganic salt (NaCl, KCl, $K_2HPO_4$, $NaH_2PO_4$, $NaH_2PO_4{\cdot}2H_2O$), NaCl gave the highest yield (~96%) and lowest partition coefficient (0.053) of paclitaxel. The optimal NaCl/solvent ratio, methylene chloride/MeOH ratio, and pure paclitaxel content for liquid-liquid extraction using NaCl were 1% (w/v), 26% (v/v), and 0.066% (w/v), respectively. Under the optimal conditions developed in the present method, most of the paclitaxel (~96%) was recovered from biomass by a single extraction step. In addition, this method facilitated 3-fold higher recovery efficiency of paclitaxel in a shorter extraction number than the conventional liquid-liquid extraction method.

• Membrane and Water Treatment
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• v.13 no.3
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• pp.147-166
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• 2022

Liquid-liquid membrane contactor (LLMC), a device that exchanges dissolved gas molecules between the two sides of a hydrophobic membrane through membrane pores, can be employed to extract ammoniacal nitrogen from a feed solution, which is transported across the membrane and accumulated in a stripping solution. This LLMC process offers the promise of improving the sustainability of the global nitrogen cycle by cost-effectively recovering ammonia from wastewater. Despite recent technological advances in LLMC processes, a comprehensive review of their feasibility for ammonia recovery is rarely found in the literature. Our paper aims to close this knowledge gap, and in addition to analyze the challenges and provide potential solutions for improvement. We begin with discussions on the operational principles of the LLMC process for ammonia recovery and membrane types and membrane configurations commonly used in the process. We then assess the performance of the process by reviewing publications that demonstrate its practical application. Challenges involved in the implementation of the LLMC process, such as membrane fouling, membrane wetting, and chemical requirements, are presented, along with discussions on potential strategies to address each. These strategies, including membrane modification, hybrid process design, and process optimization based on cost-benefit analysis, guide the reader to identify key areas of future research and development.

• Korean Journal of Animal Reproduction
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• v.22 no.1
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• pp.89-94
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• 1998

A study was made to investigate the effects of concerning factors with IGF-I recovery on the final IGF-I concentration in the effluent and to establish recovery conditions of IGF-I using liquid emulsion membranes(LEM). D2EHPA was best carrier among Amberlite LA2, Aliquit 336 and D2EHPA for recovery rate of IGF-I. Recovery rate of IGF-I by D2EHPA volume in the oil phase was increased as increasing D2EHPA volume, and optimal volume of D2EHPA was 5% in this experiment. The recovery rate of IGF-I by D2EHPA was increased by the decreasing from pH 7 to pH 4 of external phase. Therefore, optimal pH value was 4.0. Optimal concentrations of sulfuric acid in internal phase, paraffin oil in oil phase and Span 80 for recovery rate of IGF-I were 0.1M, 2.0% and 5%, respectively, and optimal W/O rate was 2. These results suggested that optimal conditions for recovery of IGF-I were D2EHPA(5%) as carrier, pH 4.0, 0.1M sulfuric acid, 2% paraffin oil, 2.0 W/O rate and 5.0% Span 80.

• Korean Chemical Engineering Research
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• v.54 no.2
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• pp.229-233
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• 2016

In this study, an efficient ultrasound-assisted liquid-liquid extraction process was developed for recovering of paclitaxel from plant cell cultures. The optimal ultrasonic power and operating time were 250 W and 15 min at fixed ratio of bottom phase, methylene chloride to top phase, MeOH (25%, v/v). Under the optimal conditions developed in the present method, most of the paclitaxel (~92%) was recovered from crude extract by a single extraction step. Due to the synergistic effect of ultrasound by the addition of inorganic salt, an appropriate inorganic salt concentration and the ultrasonic power were found to be required for the effective recovery of paclitaxel using ultrasound-assisted liquid-liquid extraction.

• Journal of Applied Biological Chemistry
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• v.55 no.3
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• pp.149-156
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• 2012

The effects of solvent type and concentration, solid/liquid ratio, extraction time and repeated extraction on recovery of keratinase from solid-state fermentation (SSF) of chicken feather by a local Streptomyces sp. NRC 13S were investigated in order to establish the experimental conditions for keratinase yield. Among solvents tested, 0.5% (v/v) glycerol was the best. Box-Behnken design was used to investigate the effect of relevant variables on keratinase recovery. The factors investigated were solid/liquid ratio (1:1.66-1:6.66 g/mL), glycerol concentration (0.5-5% v/v) and repeated extraction (1-5 cycle). The results showed that the maximum recovery of keratinase (6933.3 U/gfs) was obtained using 0.5 (v/v) glycerol as extracting solvent, in a solid/liquid ratio of 1:5 and three extraction cycles.

• Journal of Korean Society on Water Environment
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• v.20 no.2
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• pp.183-189
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• 2004

The performance of a membrane-coupled anaerobic fermenter system for the recovery of volatile fatty acids (VFAs) from liquid organic sludge was experimentally investigated. Permeation flux was stably kept around $0.2(m^3/m^2/day)$ during operational period. The membrane-coupled fermenter showed 2.2 times higher VFAs concentration and higher VFAs forming rate than those of fermenter without membrane. The fermenter with membrane proved to be an effective system for the recovery of soluble organic materials from liquid sludge.

• Korean Chemical Engineering Research
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• v.54 no.6
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• pp.753-761
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• 2016

Liquid-liquid extraction (LLE) can be used for the recovery of acetic acid from black liquor prior to bioethanol fermentation. Recovery of value-added chemicals such as acetic-, formic- and lactic acid using LLE from Kraft black liquor was studied. Acetic acid and formic acid have been reported to be strong inhibitors in fermentation. The study elucidates the effect of three reaction parameters: pH (0.5~3.5), temperature ($25{\sim}65^{\circ}C$), and reaction time (24~48 min). Extraction performance using tri-n-octylphosphine oxide as the extractant was evaluated. The maximum acetic acid concentration achieved from hydrolyzates was 69.87% at $25^{\circ}C$, pH= 0.5, and 36 min. Factorial design was used to study the effects of pH, temperature, and reaction time on the maximum inhibitor extraction yield after LLE. The maximum potential extraction yield of acetic acid was 70.4% at $25.8^{\circ}C$, pH=0.6 and 37.2 min residence time.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2011.10a
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• pp.114-116
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• 2011

By 33 CFR 154.828 regulation, a liquid seal must be installed on the inlet to vapor destruction unit in vapor control system. However, install and maintenance of liquid seal are subject to many problems in ship environment. Therefore, US Coastguard, which is the governing body of the regulation, have prepared another clause in the regulation for the exemption from previous clauses. In this paper, relevent regulation is reviewed, together with the requirements for exemption from liquid seal installation. A previous example case is also studied to propose how safety assessment for the alternative safety devices replacing liquid seal should be performed.