Precious metals enrichment from wastewater solution using emulsion liquid membrane process

Recovery of precious metals including palladium and silver from liquid waste solutions is vital, in order to sustain the resources and to conserve the environment from hazardous materials, particularly heavy metals. Many methods were studied for precious metal recovery, but constrained by several limitations. One of the promising methods for industrial wastes treatment and precious metals recovery is emulsion liquid membrane (ELM). This method able to selectively separate and concentrate the target metals through a very thin layer of liquid membrane with large surface area. In this study, an attempt was made to recover palladium and silver from liquid waste solution using bis (2,4,4-trimethylpentyl) monothiophosphinic acid (Cyanex 302) as a mobile carrier. Several important parameters affecting the ELM recovery process such as extractant/carrier and stripping agent concentration, phase treatment ratio between emulsion and feed phase were studied. The results showed that at optimum process conditions of 0.03 M Cyanex 302 carrier concentration, 1.0 M of thiourea in 1.0 M of H2SO4(1.0 M acidic thiourea) stripping agent concentration and 1:4 treat ratio, almost 100% of silver was extracted and recovered with 11 times of enrichment. Whilst for the palladium treatment, almost 100% of palladium was extracted and recovered with 3 times enrichment in the receiving phase at 0.2 M of Cyanex 302, 1.0 M acidic thioureaof striping agent and 1:3 treat ratio. Therefore, it can be concluded that the ELM system is very promising and has high potential in removal and recovery of precious metals

Emulsion stability of palladium extraction containing cyanex 302 as a mobile carrier in emulsion liquid membrane process

Emulsion Liquid Membrane (ELM) process is one of the alternative techniques to extract solutes from wastewater. It has been given considerable attention due to its advantages such as simultaneous extraction and recovery in a single step operation, non-equilibrium mass transfer, high fluxes, low energy consumption, reusability and high selectivity. The main concern in order to achieve high stability in the process is the size of internal droplets of primary emulsion. This study aims to investigate the affecting parameters such as concentration of surfactant, emulsification speed and emulsification time. ELM process containing bis(2,4,4-Trimethylpentyl) monothiophosphinic acid (Cyanex 302) as a mobile carrier in kerosene and acidic thiourea as stripping agent was used. The stability results showed that 2.8 μm of droplet diameter was formed at favorable condition of 2 % w/v surfactant concentration, 12,000 rpm of emulsification within 3 min of emulsification time. At this condition, 84 % of Palladium was extracted

Development of vegetable oil-based emulsion liquid membrane for downstream processing of bio-succinic acid

Succinic acid has been recognized as a useful platform chemical that can be applied in various industries. The application of bio-based succinic acid is still limited due to high downstream processing cost. In this study, vegetable oil-based emulsion liquid membrane (ELM) process is proposed to recover succinic acid from fermentation broth. The ELM system consists of three main liquid phases; external feed, membrane, and internal stripping. The liquid membrane phase was prepared by dissolving Amberlite LA2 and Span 80 in palm oil, while, the internal phase comprises of sodium carbonate solution, Na2CO3. The influence of feed, stripping agent and carrier concentration, treat ratio, as well as liquid membrane recycling on ELM performance were studied. The results showed 10 g/L of initial concentration, 1.0 M of Na2CO3, 0.7 M of Amberlite LA2, and treat ratio of 1:5 is the best condition with almost 100% recovery and enrichment of 21 times. The recycled liquid membrane concentrates the succinic acid up to 12 times. Therefore, the proposed ELM is a potential technology to extract bio-succinic acid

Neutral Hydrogen Mapping of Virgo Cluster Blue Compact Dwarf Galaxies

A new installment of neutral hydrogen mappings of Blue Compact Dwarf galaxies, as defined by optical morphology, in and near the Virgo cluster is presented. The primary motivation was to search for outlying clouds of HI as potential interactive triggers of the enhanced star formation, and therefore the mapped galaxies were selected for large HI} mass, large optical diameter, and large velocity profile width. Approximately half the sample proved to have one or more small, low column density star-free companion clouds, either detached or appearing as an appendage in our maps, at resolution of order 4 kpc. Comparison is made to a sample of similarly mapped field BCD galaxies drawn from the literature; however, the Virgo cluster sample of mapped BCDs is still too small for conclusive comparisons to be made. We found, on the one hand, little or no evidence for ram pressure stripping nor, on the other, for extremely extended low column density HI envelopes. The HI rotation curves in most cases rise approximately linearly, and slowly, as far out as we can trace the gas.Comment: To appear in AJ, Dec. 200

Aerodynamic Analyses and Database Development for Lift-Off/Transition and First Stage Ascent of the Ares I A106 Vehicle

NASA Langley Research Center, in partnership with NASA Marshall Space Flight Center and NASA Ames Research Center, was involved in the aerodynamic analyses, testing, and database development for the Ares I A106 crew launch vehicle in support of the Ares Design and Analysis Cycle. This paper discusses the development of lift-off/transition and ascent databases. The lift-off/transition database was developed using data from tests on a 1.75% scale model of the A106 configuration in the NASA Langley 14x22 Subsonic Wind Tunnel. The power-off ascent database was developed using test data on a 1% A106 scale model from two different facilities, the Boeing Polysonic Wind Tunnel and the NASA Langley Unitary Plan Wind Tunnel. The ascent database was adjusted for differences in wind tunnel and flight Reynolds numbers using USM3D CFD code. The aerodynamic jet interaction effects due to first stage roll control system were modeled using USM3D and OVERFLOW CFD codes

Are all noisy quantum states obtained from pure ones?

We ask what type of mixed quantum states can arise when a number of separated parties start by sharing a pure quantum state and then this pure state becomes contaminated by noise. We show that not all mixed states arise in this way. This is even the case if the separated parties actively try to degrade their initial pure state by arbitrary local actions and classical communication.Comment: 3 pages, no figure

Proposal for SPS beam time for the baby MIND and TASD neutrino detector prototypes

The design, construction and testing of neutrino detector prototypes at CERN are ongoing activities. This document reports on the design of solid state baby MIND and TASD detector prototypes and outlines requirements for a test beam at CERN to test these, tentatively planned on the H8 beamline in the North Area, which is equipped with a large aperture magnet. The current proposal is submitted to be considered in light of the recently approved projects related to neutrino activities with the SPS in the North Area in the medium term 2015-2020

Effects of antenatal betamethasone on preterm human and mouse ductus arteriosus: comparison with baboon data.

BackgroundAlthough studies involving preterm infants ≤34 weeks gestation report a decreased incidence of patent ductus arteriosus after antenatal betamethasone, studies involving younger gestation infants report conflicting results.MethodsWe used preterm baboons, mice, and humans (≤276/7 weeks gestation) to examine betamethasone's effects on ductus gene expression and constriction both in vitro and in vivo.ResultsIn mice, betamethasone increased the sensitivity of the premature ductus to the contractile effects of oxygen without altering the effects of other contractile or vasodilatory stimuli. Betamethasone's effects on oxygen sensitivity could be eliminated by inhibiting endogenous prostaglandin/nitric oxide signaling. In mice and baboons, betamethasone increased the expression of several developmentally regulated genes that mediate oxygen-induced constriction (K+ channels) and inhibit vasodilator signaling (phosphodiesterases). In human infants, betamethasone increased the rate of ductus constriction at all gestational ages. However, in infants born ≤256/7 weeks gestation, betamethasone's contractile effects were only apparent when prostaglandin signaling was inhibited, whereas at 26-27 weeks gestation, betamethasone's contractile effects were apparent even in the absence of prostaglandin inhibitors.ConclusionsWe speculate that betamethasone's contractile effects may be mediated through genes that are developmentally regulated. This could explain why betamethasone's effects vary according to the infant's developmental age at birth