Selective emulsion liquid membrane extraction of silver from photographic waste industries

The field of liquid membrane technology is currently undergoing a rapid expansion in research as well as its application as an industrial separation process. Liquid membrane can be manipulated to selectively separate a specific solute from a mixture and even to extract a solute against its concentration gradient. A liquid membrane system comprises of three liquid phases; feed phase, liquid membrane organic phase and receiving phase. Liquid membrane can be prepared using support or as emulsion (unsupported) liquid membrane. Emulsion liquid membrane is a liquid membrane in which the membrane phase of an emulsion is dispersed into the feed phase to be treated. This method was investigated as an alternative process for the recovery of silver from photographic waste, which contains various metals ions such as silver, iron, sodium and potassium. The important parameters governing the extraction process of silver such as agitation speed, homogenizer speed, surfactant and carrier concentrations, type of diluents, treat ratio and types of stripping solution were investigated. This process has been conducted in a batch system using a mixer-settler. The results show that the mobile carrier Cyanex 302 is selective towards silver and almost completely extract silver over the other metals that existed in the photographic waste. The optimum silver extraction was obtained by using 0.03 M Cyanex 302, 3 % (w/v) Span 80, 250 rpm stirring speed, 1.0 M thiourea in 1.0 M H2SO4 stripping agent, 1:5 of treat ratio, and kerosene as a diluents. The experimental result also shows that the emulsion liquid membrane system could be recycled twice having 80% of silver was extracted. In addition, theoretical studies show that the developed model could predict the extraction performance of the system understudied as obtained from experimental data

Stability of palm oil-based emulsion liquid membrane for succinic acid extraction from aqueous solution

Emulsion liquid membrane (ELM) process has high potential in the separation of succinic from the fermentation broth. However, the major drawback of this technology is the stability of emulsion globules during the extraction process and the chemical involve d in the liquid membrane formulation. This study investigate the stability of ELM using a greener formulation containing Amberlite LA - 2 as a carrier, Span 80 and Tween 80 as a surfactant, palm oil as a diluent and sodium carbonate (Na 2 CO 3 ) as an aqueous st ripping agent. The emulsion stability was evaluated by observing the water - oil separation of the emulsion and microscopic image of emulsion droplets count and size. Several operating parameters including the organic to internal ratio, homogenizer speed, ho mogenizing time, and surfactant concentration, and surfactant blend were investigated. The results show the most stable water - in - oil emulsion was observed at 3:1 organic to internal ratio; 7000rpm homogenizer speed; 5 minute emulsification time; 3% (w/v) s urfactant at HLB 8. Besides, the extraction study shows 70% of the succinic acid was extracted at 0.01M Na 2 CO 3 , 1:3 treat ratio, and 0.7M Amberlite in palm oil at optimum primary emulsion stability conditions. This indicates the potential of using palm oil based ELM for the extraction of succinic acid

Double emulsion (water-in-oil-in-water) system in succinic acid extraction - A stability study

Emulsion liquid membrane (ELM) process is a very promising method for the industrial separation process. This system offers many advantages, including simple operation, high selectivity, low energy requirement, and simultaneous step of extraction and stripping process. One of the most important aspects for a successful ELM process is emulsion stability, which is governed by emulsion swelling and breakage. Research on the stability of ELM system have been widely reported, especially for primary emulsion (water-in-oil) but very limited in double emulsion (water-in-oil-in-water) stability aspect. In this study, the stability of water-in-oil-inwater (W/O/W) was investigated by varying surfactant concentration of sorbitan monooleate (Span 80) and polyoxyethylene sorbitan monooleate (Tween 80), agitation speed, and agitation time. The results showed that the most stable W/O/W emulsion was obtained at 5 % (w/v) Span 80, 1 % (w/v) Tween 80, 300 rpm agitation speed, and 3 min of agitation time with no emulsion breakage or swelling occurred. This stable emulsion system can promote high extraction efficiency, which is 70 % of succinic acid was extracted

Liquid membrane component selection for removal of phenol from simulated aqueous waste solution

Phenol is considered as one of the environmental pollutants in various industrial effluents that needs to be removed. One of the potential methods for the removal and recovery of phenol is the emulsion liquid membrane (ELM) process. In order to prepare astable and efficient emulsion liquid membrane, selecting the components of the membrane is crucial to the process development. This research was conducted to investigate the feasibility of palm oil as an organic solvent in liquid membrane (LM) formulation for phenol extraction and to study the effects of several parameters which affect the extraction and recovery performance of phenol using liquid-liquid extraction. The feasibility of palm oil was investigated by manipulating the organic solvent used, either palm oil or a mixture of palm oil and kerosene. Several parameters such as type of carrier, carrier concentration, type of stripping agent and stripping agent concentration were varied during LM component selection. The results showed that mixed palm oil and kerosene provides a high potential as an organic solvent for the extraction of phenol. About 71% of phenol was extracted at a palm oil to kerosene ratio of 70:30 and assisted with shorter time of phase separation between loaded organic and phenol feed phase. The addition of 0.1M of TBP (tributyl phosphate) as a carrier increased the extraction of phenol to 86% and prevented the third phase formation. Meanwhile, 2M of sodium hydroxide was able to act as a stripping agent to recover 81% of the phenol from the overall process. It can be concluded that palm oil has shown great potential in extracting phenol and could be applied in an ELM process as a green solvent for an emulsion liquid membrane process

D2EHPA-sulfuric acid system for simultaneous extraction and recovery of nickel ions via supported liquid membrane process

This research addresses the extraction and recovery of nickel ions from real electroplating wastewater using supported liquid membrane (SLM) process. The process involves three main phase system which are feed, organic and stripping phase. The feed phase containing the nickel electroplating wastewater whereas the organic phase containing the liquid membrane which was immobilized in the membrane support. The liquid membrane was prepared by dissolving certain concentration of D2EHPA in kerosene which acts as a carrier and diluent, respectively. Meanwhile, the membrane support employed was commercial polypropylene membrane with features of 100 µm thickness, 71.9% porosity and 0.10 µm effective pore size. On the other hand, the stripping phase consisting of sulfuric acid (H2SO4) solution which acted as a stripping agent. Parameters such as carrier and stripping agent concentration and feed phase flowrate were examined to obtain the best condition for the extraction and recovery efficiency of nickel. The results revealed that about 44 and 55% of nickel ions successfully extracted and recovered, respectively at the best conditions of 1.0 M of D2EHPA, 3.0 M of H2SO4 and 70 ml/min flowrate of feed phase

The use of factorial design in screening of factors influencing hexavalent chromium extraction by continuous green emulsion liquid membrane

Recently, increasing concerns on hexavalent chromium as an environmental pollutant can be observed due to its build-up to toxic levels in the environment, resulting from various industrial and agricultural activities such as electroplating, stainless steel production, leather tanning and textile manufacturing. This work screens the significant factors that largely affect the efficiency of hexavalent chromium (Cr(VI)) removal from electroplating wastewater in continuous green emulsion liquid membrane using fractional factorial design. There are six factors investigated for affecting the removal of chromium which are residence time (t), TOMAC concentration (M), stripping agent concentration (M), rotational speed (rpm), treat ratio, and modifier concentration (w/v). The response variable of the chromium removal was identified using the two-level fractional factorial (two level) design and the results were analyzed statistically. Five factors were identified to have significant influence on chromium removal which are retention time, rotational speed, treat ratio, modifier concentration and carrier concentration. Regression models for chromium extraction were developed and the adequacy of the model was examined. The results of this study indicate that fractional factorial design is capable to predict the significant factors affecting hexavalent chromium extraction by using continuous green emulsion liquid membrane

Synergistic organic liquid formulation for succinic acid extraction from simulated aqueous solution

Bio-succinic acid (SA) is a new compound that will replace petroleum based succinic acid. The application of bio-based succinic acid is still restricted due to its excessive downstream processing cost. Liquid-liquid extraction (LLE) is one of the promising methods for the successful extraction of SA. Single extractant in the LLE formulation commonly had drawbacks of long extraction time and tiny loading capacity. The aim of this study is to create synergistic formulation to enhance the SA extraction performance. The diluent is fixed as palm oil as the characteristic shows that it is safer, renewable, and non-toxic to environment. Four different types of extractants including Aliquat 336, Trioctylamine (TOA), Tributylamine (TBA) and Tributyl-phosphate (TBP) was tested to find the best combination of synergist extractants. The result shows that almost 100 % of SA was extracted using synergistic mixture of TOA and Aliquat 336 at 0.2M with synergistic coefficient (SC) of 640. In conclusion, synergistic mixture has high potential to extract SA

Numerical prediction performance of Kraft lignin extraction using boundary breakage model

This study predicts the performance of kraft lignin extraction using emulsion liquid membrane (ELM) from pulping wastewater using boundary breakage model. The model was developed based on the previous study with some modifications and assumptions. Therefore, in developing kraft lignin extraction model, it will consider emulsion globule approach and the emulsion swelling and breakage during the ELMs process. It was found to be numerically stable and reliable in predicting the behavior of kraft lignin extraction using ELM for long duration of time. MATLAB software was used to predict the performance of ELM on extracting kraft lignin from pulping wastewater based on the model developed. At optimum condition, the simulation prediction result was found to have a small deviation with the experimental data on extraction efficiency. The model was computed with some parameter effects including initial feed concentrations; treat ratio and agitation speed, which demonstrated that the prediction results were in agreement with the theoretical study of ELM. The data instills confidence in the model as a useful prediction model on kraft lignin removal by ELM process in pulping industry

Oleic acid enhancement in used frying palm oil via enzymatic acidolysis

The extensive amount of used frying palm oil (UFO) generated in Malaysia has caused serious environmental problems. Management of the waste faces a significant challenge especially on choosing the appropriate method by considering the possibilities of contaminating the environment. This study aims to add value to UFO by producing high oleic palm oil. Enzymatic acidolysis using lipase was employed to incorporate oleic acid in the UFO. This study also investigated the effect of enzymatic loading, reaction time and water content on the properties of modified UFO as to find the optimum condition for oleic acid incorporation. Oleic acid incorporation was quantified based on peroxide and iodine values. The optimum conditions for acidolysis process were obtained at enzyme loading of 30% (w/w), reaction time of 24 hours, and water content of 2% (w/w) with substrate mole ratio of 1:2 (UFO: oleic acid) and temperature of 50 °C. At optimum conditions, the modified used frying palm oil (MUFO) has peroxide and iodine values of 19.00 ± 0.99 meq/mg and 31.5 ± 0.42 mg/mg, respectively. After the acidolysis reaction, oleic acid concentration has increased from 27.00 ± 0.70% (v/v) to 62.34 ± 1.29% (v/v), demonstrating their feasibility as a substrate for structured lipid production