Raja Norimie Raja Sulaiman

Selective removal and recovery of Black B reactive dye from simulated textile wastewater using the supported liquid membrane process

Effluent containing colour/dyes, especially reactive dyes, becomes a great concern of wastewater treatment because it is toxic to human life and aquatic life. In this study, reactive dye of Black B was separated using the supported liquid membrane process. Commercial polypropylene membrane was used as a support of the kerosene–tridodecylamine liquid membrane. Several parameters were tested and the result showed that almost 100% of 70 ppm Black B was removed and 99% of 70 ppm Black B was recovered at pH 2 of the feed phase containing 0.00001 M Na2SiO3, flow rate of 150 ml/min and 0.2 M NaOH. The membrane support also remained stable for up to 36 hours under an optimum condition.

Synergistic green extraction of nickel ions from electroplating waste via mixtures of chelating and organophosphorus carrier

The discharge of electroplating waste containing nickel ions has led to environmental issues owing to the toxicity problem mainly to the aquatic organisms and humans. Liquid-liquid extraction offers a great potential treatment for nickel removal with several advantages of simple, high efficiency and high separation factor. In this study, a green synergistic liquid-liquid extraction of nickel ions from electroplating waste solution using chelating oxime (LIX63) and organophosphorus (D2EHPA) carriers individually as well as their synergistic mixture has been studied. The result demonstrated that about 83% of nickel ions have been successfully extracted via the mixture system of 0.08M LIX63 +0.02M D2EHPA with the maximum synergistic enhancement factor, Rmax of 29.56. Meanwhile, the back extraction study also revealed that HNO3 was the most suitable stripping agent while the diluent screening also showed that palm oil has high potential to be incorporated as a diluent in the green synergistic liquid-liquid extraction of nickel.

Recovery of ionized nanosilver by emulsion liquid membrane process and parameters optimization using response surface methodology

The discharge of silver ions from nanosilver-based product into the environment has raised the ecological and human health concern due to the toxicity of silver ion, particularly on the release behaviour of ionized nanosilver from the wastage. Therefore, recovery of ionized nanosilver is highly necessary. In this research, emulsion liquid membrane technique was employed for ionized nanosilver recovery from the domestic waste. The liquid membrane consists of kerosene, Span 80, Cyanex 302 and acidic thiourea as the diluent, surfactant, carrier and stripping agent, respectively. The emulsion stability was investigated at different surfactant concentrations, agitation and homogenizer speeds. Response surface methodology (RSM) was applied for the optimization of process variables including treat ratio, sulphuric acid (H2SO4) and thiourea concentration in the recovery process. The results showed that the most stable emulsion was observed at 3% w/v of surfactant, 10,000 and 150 rpm of homogenizer and agitation speed, respectively. The optimum conditions obtained for the recovery process using RSM were: treat ratio (0.256), H2SO4 concentration (0.75 M) and thiourea concentration (0.85 M). At the optimized condition, the maximum recovery of ionized nanosilver was 84.74%.

Simultaneous extraction and enrichment of reactive dye using green emulsion liquid membrane system

ABSTRACT Currently, an extractive green palm oil-based emulsion liquid membrane (ELM) has been used for simultaneous extraction and enrichment of Reactive Red 3BS from simulated synthetic dye wastewater. The ELM consists of two main phases, which are organic liquid membrane (LM) and stripping solution. During the extraction process, the ELM was dispersed into the simulated synthetic dye wastewater containing the Reactive Red 3BS complexes. The organic LM contains tridodecylamine (TDA), Sorbitan Monooleate (Span 80) and palm oil as a carrier, surfactant and diluent, respectively. The sodium bicarbonate (NaHCO3) was used as stripping solution for the enrichment process. Several important parameters that affected the simultaneous extraction and enrichment of Reactive Red 3BS, such as carrier and stripping agent concentrations, extraction time and treat ratio, were investigated. The results showed that almost 90% of Reactive Red 3BS ions were successfully extracted with 10 times enrichment in the stripping phase at the optimum conditions of 0.2 M TDA, 0.1 M NaHCO3, 5 min of extraction time and 1:5 of treat ratio. Hence, it can be concluded that palm oil possesses a high potential as green diluent in future technology, especially in ELM process for the removal and recovery of Reactive Red 3BS from synthetic dye wastewater.

Extraction of Ionized Nanosilver by Emulsion Liquid Membrane Using Cyanex 302 as a Mobile Carrier

Nowadays, nanosilver is increasingly used in various fields such as consumer products and medicinal application. The ionization of nanosilver in wash water inhibits the beneficial bacterial growth that damages the cell due to their toxicity effect. Therefore, the removal of ionized nanosilver is greatly required in order to protect the environment especially from the aquatic organism. One of the promising techniques is an emulsion liquid membrane (ELM) process. In this study, the emulsion liquid membrane process is conducted to treat wash water containing nanosilver. The process has been carried out in a batch process using a mixer-settler, and silver ion concentration is measured using atomic absorption spectrometry (AAS). The membrane phase consists of kerosene as a diluent, Cyanex 302 as an extractant, Span 80 as a surfactant, and a H2SO4 solution as a stripping agent. The activity of sulfur-containing extractant (Cyanex 302) toward facilitating the transport of nanosilver ion from wash water through an emulsion liquid membrane has been studied. The optimum condition was established by investigating the effect of Cyanex 302 concentrations, extraction time, and agitation speed. The results showed that almost 70 % of ionized nanosilver was extracted from the simulated wash water. The highest removal of ionized nanosilver was achieved at the concentration of 0.05 M Cyanex 302, 15 min of extraction time, and 150 rpm of agitation speed. Consequently, Cyanex 302 possesses a high potential as a mobile carrier in the extraction of ionized nanosilver from wash water.