Reuse of waste cooking oil (WCO) as diluent in green emulsion liquid membrane (GELM) for zinc extraction

Zinc (Zn) was identified as one of the most toxic heavy metals and often found contaminating the water sources as a result of inefficient treatment of industrial effluent. A green emulsion liquid membrane (GELM) was proposed in this study as a method to minimize the concentration of Zn ions in an aqueous solution. Instead of the common petroleum-based diluent, the emulsion is reformulated with untreated waste cooking oil (WCO) collected from the food industry as a sustainable and cheaper diluent. It also includes Bis(2-ethylhexyl) phosphate (D2EHPA) as a carrier, Span 80 as a surfactant, sulfuric acid (H2SO4) as an internal phase, and ZnSO4 solution as an external phase. Such formulation requires a thorough understanding of the oil characteristics as well as the interaction of the components in the membrane phase. The compatibility of WCO and D2EHPA, as well as the external phase pH, was confirmed via a liquid-liquid extraction (LLE) method. To obtain the best operating conditions for Zn extraction using GELM, the extraction time and speed, carrier, surfactant and internal phase concentrations, and W/O ratio were varied. 95.17% of Zn ions were removed under the following conditions; 0.001 M of H2SO4 in external phase, 700 rpm extraction speed for 10 min, 8 wt% of carrier and 4 wt% of surfactant concentrations, 1:4 of W/O ratio, and 1 M of internal phase concentration.

Optimisation of operating conditions during coagulation-flocculation process in industrial wastewater treatment using Hylocereus undatus foliage through response surface methodology

In exploring the application of natural coagulants in industrial wastewater treatment, plant-based coagulants have been gaining more interests due to their potential such as biodegradability and easy availability. Hylocereus undatus foliage as a plant-based coagulant has been proven to be efficient during the coagulation-flocculation process; however, limited research has been reported focusing only on palm oil mill effluent (POME) and latex concentrate wastewater. In addition, no previous study has been carried out to determine the performance evaluation of Hylocereus undatus foliage in treating different types of wastewater incorporating different operating conditions using optimization techniques. Hence, this study employed response surface methodology (RSM) in an attempt to determine the performance evaluation of the coagulant in paint wastewater treatment. Four independent factors such as the pH value, coagulant dosage, rapid mixing speed and temperature were chosen as the operating conditions. Three water parameters such as turbidity, chemical oxygen demand (COD) and suspended solids (SS) were chosen as responses in this study. Results revealed that through central composite design (CCD) via Design Expert software, the optimum conditions were achieved at pH 5, coagulant dosage of 300 mg/L, rapid mixing speed of 120 rpm and temperature at 30 °C. The experimental data was observed to be close to the model predictions with the optimum turbidity, COD and SS removal efficiencies found to be at 62.81%, 59.57% and 57.23%, respectively.

Reuse of Waste Cooking Oil (WCO) as Diluent in Green Emulsion Liquid Membrane (GELM) for Zinc Extraction.. [DOI: 10.21203/rs.3.rs-1251988/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

Zinc (Zn) was identified as one of the most toxic heavy metals and often found contaminating the water sources as a result of inefficient treatment of industrial effluent. A Green Emulsion Liquid Membrane (GELM) was proposed in this study as a method to minimize the concentration of Zn ions in an aqueous solution. Instead of the common petroleum-based diluent, the emulsion is reformulated with untreated waste cooking oil (WCO) collected from the food industry as a sustainable and cheaper diluent. It also includes Bis(2-ethylhexyl) phosphate (D2EHPA) as carrier, Span 80 as surfactant, sulfuric acid (H2SO4) as internal phase and ZnSO4 solution as external phase. Such formulation requires a thorough understanding of the oil characteristics as well as the interaction of the components in the membrane phase. The compatibility of WCO and D2EHPA, as well as the external phase pH was confirmed via liquid-liquid extraction (LLE) method. To obtain the best operating conditions for Zn extraction using GELM, the extraction time and speed, carrier, surfactant and internal phase concentrations, and W/O ratio were varied. 95.17% of Zn ions were removed under the following conditions; 0.001M of H2SO4 in external phase, 700 rpm extraction speed for 10 minutes, 8 wt% of carrier and 4 wt% of surfactant concentrations, 1:4 of W/O ratio and 1 M of internal phase concentration.

Characterized raw Leucaena leucocephala pod (LLP) as biosorbent produced high adsorption of Pb(II) ions in a synthetic aqueous solution.. [DOI: 10.21203/rs.3.rs-1495714/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

Biosorbent from a plant-based material with characterized properties is important to remove heavy metals hence reduce the impact on humans and aquatic life. This study proposes to remove Pb(II) in a synthetic aqueous solution using characterized plant-based raw Leucaena leucocephala pod (LLP) via adsorption experiment. The effects of pH synthetic aqueous solution and raw LLP dosage on Pb(II) adsorption were investigated. The characteristics of raw LLP before and after adsorption of Pb (II) were also studied. It was found that the highest adsorption capacity of Pb(II) was obtained at pH 5 of synthetic solution with 1.1 mg/g adsorption capacity. Meanwhile, the optimum dosage of raw LLP was 40 g/L at 30 min retention time, resulting in 93% of Pb(II) removal. Optimum removal of Pb(II) using raw LLP in this study was obtained under low retention time of adsorption process compared to other studies using others plant based biosorbent but comparable in terms of heavy metal removal. Raw LLP can be effectively used directly without modification as a biosorbent in removing Pb(II) in industrial waste, hence provides an alternative method for pollutants removal which is safe for the environment and abundantly available.