Table 3 shows the magnetic and surface area characteristic of bentonite and bentonite-Fe3O4 composites. Magnetic measurements of bentonite and bentonite-Fe3O4 composites at 293 K. Bentonite particles show no value of saturation magnetization. The process of coating Fe3O4 which has a higher value of saturation magnetization onto bentonite surface caused composites having magnetic properties. The saturation magnetization increased with an increase of Fe3O4 content. Study of silica coated magnetite particles (Fe3O4/SiO2) indicated that saturation magnetization is lower than Fe3O4 [11]. The surface area of composite decreased with increasing content of Fe3O4, because most of the pores in the bentonite blocking with Fe3O4. Futhermore, BET surface …show more content…
The increases in the pH of acid mine drainage synthetic with different weight of adsorbent show in figure 2. The pH of solution was observed that increased with increasing in weight of adsorbent from 0.1 to 0.8 g. The mechanism interaction between bentonite and cation is adsorption and ion exchange [19]. There is competition between H+ and metals ion in the solution for the exchange of cations in the bentonite. The adsorption of Cu and Ni using bentonite showed an increase in pH resulted in an increased in metal ions removal …show more content…
However, adsorption process using bentonite much longer than composites. In addition, the separation of bentonite from the solution requires filter. If using bentonite-Fe3O4 composite, separation without filter. The separation can be using permanent magnet. Treatment of acid mine drainage synthetic using bentonite-Fe3O4 composite (2:1) having final concentration of Fe2+, Cu2+, Zn2+ and Mn2+ were 5.66, 14.09, 15.34 and 21.75 mg/L, respectively. Therefore, it is recommended to use the bentonite-Fe3O4 composite (2:1) to treatment acid mine drainage. The adsorption efficiency for all adsorbent increases in the order Mn2+< Zn2+< Cu2+< Fe2+. The same result in the adsorption process using bentonite blended limestone while adsorption efficiency to the Mn2+ of the smallest compared to other metal ions such as Fe, Co, Cr, Cu, Pb and Zn [22]. Another study that bentonite adsorption affinity order of the metal ions from acid mine drainage was Zn
Solutions of 6M H2SO4, 6M NH3, 6M HCl, 6M NaOH, and 1.0 M of NaCl, 1M Fe(NO3)3, 1M NiSO4, 1M AgNO3, 1M KSCN, 1M Ba(NO3)2, and 1M Cu(NO3)2 were given in separate test tubes. The color of possible precipitates, ions, acid-base behaviour, odor and solubility rules were conducted and were reported in Table 1. The key information about a mixture of two solutions was
The main pollutant of surface water in the mid-Atlantic region is Acid Mine Drainage, AMD, also called Abandoned Mine Drainage. AMD is a nonpoint source pollution that has degraded more than 4,500 stream miles, in just the mid-Atlantic region, due to the drainage of metal-rich water from mining activities (Jacobs). The runoff is extremely acidic due to the exposure of pyrite containing rocks, a sulfur bearing mineral (FeS2), during mining activities, and the chemical reactions associated with the contact of air and water with such rocks. As a result of such chemical reactions, sulfuric acid (H2SO4) is produced. Several chemical reactions take place and are as follows:
The mass percent of water was determined using the mass of water and dividing it by the total mass of the hydrate and then multiplying that answer by 100%. The number of moles of water in a hydrate was determined by taking the mass of the water released and dividing it by the molar mass of water. The number of moles of water and the number of moles of the hydrate was used to calculate the ratio of moles of water to moles of the sample. This ratio was then used to write the new and balanced equation of the dehydration process. The sample was then rehydrated to the original state and the percent of the hydrate recovered was calculated by using the mass of the rehydrated sample by
Wollastonite is a calcium inosilicate mineral which has industrial importance worldwide because of its properties. It is used in many industries mostly by tile factories which have incorporated it into the manufacturing of ceramic to improve many aspects. Wollastonite is typically associated with Calcite, Diopside, and Garnet as minor components, and the main aim of the test was to investigate a physical separation process that can recover 90% Wollastonite. The test work was conducted on 6 ton material with top size of -1.2mm running at head grade of 53% Wollastonite. The scoping characterisation of the ore was conducted using Hpgr, Permanent magnetic rolls, Winnower and Electrostats. The Hpgr results showed that there was no significant difference
Thomas and Fray (1981) studied leaching of oxide zinc materials with chlorine and chlorine hydrate. They found that the rate of leaching of the Adrar Turkish ore could be described using a shrinking core diffusion model, and that the rate of leaching was controlled by surface reaction. In all cases studied, lead was also leached with zinc. However, iron oxides remained virtually undissolved. Frenay (1985) investigated leaching of oxidized zinc ores in various solution media and obtained the best leaching results with sulfuric acid and caustic soda. Mineralogical studies showed that smithsonite can be completely leached but hemimorphite is relatively refractory to leaching. Abdel-Aal (2000) studied the kinetics of sulfuric acid leaching of low-grade zinc silicate ore and reported that about 94% of zinc can be leached after 180 min of reaction with 10% sulfuric acid at 70°C. Espiari et al., 2006 studied hydrometallurgical treatment of tailings with high zinc content using sulfuric acid and reported that the
Acid rain also impacts other natural substances such as the limestone. Limestone is a type of sedimentary rock that reacts easily with acid. (National Geographic, 2006) This is because limestone is mostly composed of mineral calcium carbonate, which is not very soluble. (CaCO3). Because of this, the rock will dissolve but the process will be largely gradual. But with the addition of an acid, hydrogen ions (H+) will be added. This will cause the reaction with the carbonate to form hydrogen carbonate (HCO3- ions) which are very soluble in water, and the limestone will dissolve.
Filtration of textile wastewater before it is released into drains is seen to be brilliant idea in order to conserve our river. Activated carbon is known for its capability in removing organic compounds and pollutants from liquid and gas streams efficiently. However, conventional activated carbon available in the
The research work is on determination of optimum dosage of soda ash or lime in treating underground water in Makurdi metropolis. In the course of carrying out the work, samples of borehole and well water from five different locations of the study area (Makurdi) were obtained and analyzed in Benue State water works. The sample were analyzed to ascertain the level of hardness in samples and to determine the optimum values of soda ash (Na2CO3) and lime (Ca(OH)2) that will be used in reducing hardness and treating the sample in the study area. The locations were, North Bank, Wurukum, Wadata, High Level and Kanshio. The hardness level in the study area was found to range from 200mg/L to 80mg/L averagely; this was found to lay outside the WHO (1993) drinking water standards of 75mg/L to 100mg/L. On analysis, the hardness was found to range from 76mg/L to 100mg/L (borehole) at optimal level. Which was found to range within the WHO (1993) drinking water standard. While for well, range from 20mg/L to 80mg/L at optimal level. Which was
The characteristics of the biochar derived from pine fruit residue are shown in Table -1. The adsorptive properties of sorbent are greatly dependent on their particle size and distribution throughout the mass. Effective size and uniformity coefficient are the two important parameters for treatment of contaminated water using adsorbent as filtering media in column operation where control of particle size is critical. The effective size corresponds to the sieve size through which 10% of the material will pass, and the uniformity coefficient is the ratio of the sieve size that will just pass 60% of the material to the effective size. Generally, the rate of adsorption get enhanced as the particle size decreases due availability of increased surface area. Therefore, the adsorbent with smaller effective sizes provide better adsorption capacity due to better the access to the surface area and faster the rate of adsorption. The typical range of effective size and uniformity coefficient for activated carbon as adsorbent media practiced satisfactory is D10 = 0.15-0.35 mm and Cu = 2-3 respectively. In our case, Table 1 shows that the biochar prepared have an effective size of 0.055 mm and uniformity coefficient 2.87. The more uniform adsorbent media is expected to provide the slower head loss buildup and therefore, careful consideration of particle sized distribution is must for dynamic column design.
Mahdavi et al. (2012) reported that the removal of Ni, Cu, As, Sr, Mo and Ba by Parachlorella kessleri, from Syncrude tailings pond water was significantly enhanced by high concentrations of nitrogen and phosphorus, whereas the high nutrient concentrations adversely affected the removal of Co, Ni, As, Sr and Mo in samples of Albian tailings pond water. In order to make it more suitable for biosorption process, algae waste obtained after oil extraction, have been activated by alkaline treatment and used for cadmium(II) removal in batch and column systems. For batch systems, the effect of initial cadmium(II) concentration and contact time was studied in optimal experimental conditions (pH of 5.0, 8 g biomass L-1). Langmuir isotherm model and pseudo-second order kinetics model describe the experimental data well. For column studies, the alkaline treated algae waste biomass was mixed with an industrial ion exchanger resin (Purolite A-100) in order to prevent the clogging of column. Bohart-Adams, Thomas and Yoon-Nelson models were used to fit breakthrough curves obtained under varying conditions. Five biosorption/desorption cycles have yielded between 98.83 and 92.39% biosorbent regeneration. The biosorbent could efficient remove cadmium (II) from industrial wastewater, and obtained effluent has
In this work, we assessed the Cr phytoremediation potential of jute and kenaf with the idea of combining phytoremediation and the production
It is known that converting the non-linear regression to linear form of most kinetic models may lead to positive or negative effect on determining the kinetic parameters of the adsorption process [34]. In this study non-linear and linear regression (using software Origin 8.6)of pseudo first-order, pseudo second-order and Elovich kinetic models(Table 1) were used to investigate the kinetic sand the best fit model for the uptake of MB by ZnO/CR powder at different temperatures(10, 20, 30 and 40 °C).In addition different statistical error analysis functions such as , and SSE (equations 13 - 15) were used to evaluate the validity of the used models and to investigate the mechanism of the adsorption process.
Acid mine drainage is most common with hardrock mines where metal ore is bound together with sulfur. The increased acidity created from acid mine drainage has a series of negative effects, depending on the severity of change in the pH level. The acid mine drainage creates inhospitable environments to aquatic life in river systems and former mine sites, with the exception of "extremophile" bacteria (Coil, D., McKittrick, E., and Higman, B., 2010). Acid mine drainage can severely degrade the quality of the water, especially if it's a essential water supply.
Compound precipitation is one of the regularly utilized and traditional procedures for overwhelming metals expulsion from wastewater including copper. Precipitation is generally utilized because of its straightforward and modest nature. The customary compound precipitation forms incorporate hydroxide and sulphide precipitation, Chelation/complexation. It is hard to consent to stringent natural controls utilizing ordinary compound precipitation prepare. Chelating precipitants, for
A linear regression was applied to equation 4 and the values of No and ka were computed from the slope and intercept of the BDST plot between ln(Co/Ct -1) versus t at different adsorption parameters such as flow rate, bed height and influent adsorbate concentration. These BDST parameters were used to predict the maximum metal uptake capacity (qcal) under different process conditions and were compared with the experimental values (qexp) in relation to the estimated values of ka and No. As shown in Table 1a and b, the values ka decreased with increasing bed depth and influent metal concentration, but increase with increasing flow rates. Meanwhile, the values of No declined with the increase in bed height and flow rate. This trend can be explained on the fact that at increased bed heights more number of active sites is available for sorption to give higher total metal uptake but reduced per unit removal, whereas at increased flow rate the volume of adsorbate that entered the column was higher and caused the bed to saturate early. As with increased metal concentration, the No values were found to be increasing due to higher loading of metal on the adsorbent achieved in a short period of contact. This discussion shows that the overall kinetics of adsorption process is governed by external mass transfer. (aa26, aa7,aa14, aa27)