Synthesis of Indonesian Kaolin-nZVI (IK-nZVI), Evaluation for the Removal of Pb(II) from Waste Streams

Removal of toxic pollutants such as heavy metals from wastewater is of utmost importance in the current century. Heavy metals have severed a big problem in the world. Several tools have been established to mitigate this problem. In this research paper, Indonesian Kaolin-nano zerovalent iron (IK-nZVI) was synthesized as a model adsorbent for Pb(II) removal from wastewater. The efficiency of IK supported nZVI for Pb(II) removal efficiency was estimated by accompanying batch experiments. The examined parameters included the amount of IK-nZVI, the concentration of Pb(II) removal and the effect of pH. The results revealed that the IK-nZVI was efficient for the removal of Pb(II) from waste water. © 2020 Author(s).The author Lakkaboyana Sivarama Krishna is grateful to the Graduate School and The Thailand Research Fund (IRG578001), Chulalongkorn University for providing financial support, Senior Postdoctoral Fellowship under Rachadapisaek Sompote Fund

Indian Jujuba Seed Powder as an Eco-Friendly and a Low-Cost Biosorbent for Removal of Acid Blue 25 from Aqueous Solution

Indian jujuba seed powder (IJSP) has been investigated as a low-cost and an eco-friendly biosorbent, prepared for the removal of Acid Blue 25 (AB25) from aqueous solution. The prepared biomaterial was characterized by using FTIR and scanning electron microscopic studies. The effect of operation variables, such as IJSP dosage, contact time, concentration, pH, and temperature on the removal of AB25 was investigated, using batch biosorption technique. Removal efficiency increased with increase of IJSP dosage but decreased with increase of temperature. The equilibrium data were analyzed by the Langmuir and the Freundlich isotherm models. The data fitted well with the Langmuir model with a maximum biosorption capacity of 54.95 mg g−1. The pseudo-second-order kinetics was the best for the biosorption of AB25 by IJSP, with good correlation. Thermodynamic parameters such as standard free energy change (ΔG0), standard enthalpy changes (ΔH0), and standard entropy changes (ΔS0) were analyzed. The removal of AB25 from aqueous solution by IJSP was a spontaneous and exothermic adsorption process. The results suggest that IJSP is a potential low-cost and an eco-friendly biosorbent for the AB25 removal from synthetic AB25 wastewater

Sorption parameters of Pb and Cu on natural clay soils from Selangor, Malaysia = Parameter penjerapan logam Pb dan Cu oleh tanah lempung dari Selangor, Malaysia

The sorption parameters of two heavy metals (i.e. Pb and Cu) in clay soils from Selangor were studied using batch equilibrium test. The test was conducted in two separate systems, i.e. single and mix solutions. The sorption isotherms data from this test were then used to calculate the sorption parameters, i.e. distribution coefficient (Kd) and maximum adsorption capacity (Am). Langmuir sorption equation was used to model the sorption data with the correlation coefficients(r2) higher than 0.6. The study has revealed that different soils have different sorption capacity for different heavy metals. The Kd values are proportional to the sorption capacity of the soils. The sorption of Pb and Cu in single solution is higher than in mix solution, due to the competition for sorption sites among heavy metals in mix solution. The Kd values for Pb in single solution ranging from 36.18 – 334.48 L/g and for Cu is 9.29-66.19 L/g. In mix solution, the Kd values for Pb and Cu are much smaller, ranging from 23.13-31.79 L/g and 3.95-18.53 L/g respectively. The Am values in single solution for both Pb and Cu are ranging from 0.48-1.09 mg/g dan 0.18-0.70 mg/g respectively. While in mix solution, the values of Am for Pb ranging from 0.20-1.11 mg/g and Cu within 0.18-0.60 mg/g

Influence of amang (Tin Tailing) on geotechnical properties of clay soil (Pengaruh amang timah terhadap sifat geoteknik tanih lempung)

Amang or tin tailing is commonly found in the vicinity of disused mining area and responsible in downgrading the water quality, landscape and mechanical behaviour of soils. It was generated from extraction process of separating valuable metal from particular ore. This paper presents the geotechnical characteristics of amang-contaminated clay soil. The geotechnical properties of uncontaminated soils were studied in order to compare to that of amangcontaminated soils. The base soil used in this study represents completely weathered horizon of metasedimentary rock. Meanwhile, tin tailing sample was taken from the disused mine at Sungai Lembing, Pahang. The geotechnical characterisations of base soil and contaminated soils were determined based on consistency index, compaction behaviour, hydraulic conductivity and undrained shear strength (UU tests). Contaminated soil samples were prepared by adding 5, 10 and 20% of tailing, based on dry weigh of the studied base soil. The results from the particle size distribution analysis showed that residual soil from metasedimentary rock comprised 42.6% clay, 32.2% silt and 25.2% sand whilst tailing was dominated by 98% of sand fraction. XRD analysis indicated the presence of quartz, kaolinite and muscovite minerals in the studied soil. The specific gravity of soil used is 2.67 and the pH is 3.88. Tailing found to have higher specific gravity of 3.37. The consistency index of contaminated soils showed that liquid limit, wL and plastic limit, wP decreased with the increase in the percentage of tailing added to the soil samples. The value of maximum dry density, ρ dry max increased while optimum moisture content decreased due to the increase in tailing content in soil sample. The permeability of contaminated soil also increased with the increase in tailing contents ranged from 19.8 cm/hr to 23.8 cm/hr. The undrained shear strength, Cu, of contaminated soil decreased from 646 kPa (5% of tailing) to 312 kPa (20% of tailing) suggesting that the presence of tailing has influenced the geotechnical properties on the studied soil

Effect of cetyltrimethylammonium bromide on the biosorption of Acid Blue 25 onto Bengal gram fruit shell

This study explores an intensive investigation of the effect of cationic surfactant, cetyltrimethylammonium bromide (CTAB) on biosorption of Acid Blue 25 (AB25), an anionic dye, onto Bengal gram fruit shell (BGFS) from aqueous solution. The BGFS was characterized using Fourier transform infrared spectroscopy and scanning electron microscopy. Effect of AB25 and CTAB concentrations, time and temperature, were explored. The dye uptake by the BGFS was increased with increasing initial dye concentration up to 100 mg L-1. The inclusion of 0.9 mmol L-1 of CTAB in the biosorption medium was greatly improved for the removal of AB25. The AB25 uptake was better described by the Langmuir adsorption model than the Freundlich model. This study shows that the maximum uptake of AB25 dye by BGFS in the absence of surfactant was evaluated and found 29.4 mg g-1. Also, the results of this investigation revealed that the presence of 0.9 mmol L-1 CTAB in the biosorption medium increased the maximum uptake of AB25 to 166.6 mg g-1, which is 5.7 times higher than the uptake capacity in the absence of CTAB. The biosorption kinetics was correctly described by the pseudo-second-order kinetic model for all cases studied a confirmation that a chemisorption process controlled the biosorption rate. Thermodynamic parameters (ΔH°, ΔS°, and ΔG°) were determined for the biosorption of AB25 onto BGFS-CTAB. The biosorption process describes that the reaction was exothermic and spontaneous processes