Ekrem Kalkan

Removal of cobalt (II) ions from aqueous solution by using alternative adsorbent industrial red mud waste material

This study on the removal of cobalt ions from aqueous solutions by red mud was conducted in batch condition. Its objective was to investigate the possibility of using red mud waste material as an alternative to high cost commercial adsorbent materials for the removal of cobalt from aqueous solution. In this study, batch experiments were carried out for the adsorption of cobalt onto red mud industry waste. The red mud waste material was successfully used for the removal of cobalt ion from aqueous solution and the technique appears industrially applicable and viable. The potential of economically cheap waste materials like red mud was assessed for cobalt adsorption from aqueous solutions. The operating variables studied were contact time, initial solution pH, initial metal concentration, temperature and adsorbent dosage. The experimental investigation results show that activated red mud has a high level of adsorption capacity for cobalt ion. The adsorption data was correlated with the Langmuir and Freundlich isotherm models. It was found out that the Langmuir and Freundlich isotherms fitted well to the data. Consequently, it was concluded that the red mud can be successfully used for the removal of the cobalt ions from the aqueous solutions with heavy metals.

Using marble wastes as a soil amendment for acidic soil neutralization.

One of the most important factors limiting plant growth is soil pH. The objective of this study is to determine the effectiveness of marble waste applications on neutralization of soil acidity. Marble quarry waste (MQW) and marble cutting waste (MCW) were applied to an acid soil at different rates and their effectiveness on neutralization was evaluated by a laboratory incubation test. The results showed that soil pH increased from 4.71 to 6.36 and 6.84 by applications of MCW and MQW, respectively. It was suggested that MQW and MCW could be used as soil amendments for the neutralization of acid soils and thus the negative impact of marble wastes on the environment could be reduced.

Removal of textile dye Reactive Black 5 from aqueous solution by adsorption on laccase-modified silica fume

AbstractTextile wastewater with the dye is released in various ways into the environment and it causes significant environmental problems. Due to the stability of modern dyes, conventional biological treatment methods for industrial wastewater are ineffective, resulting in an intensively colored discharge from the treatment facilities. Thus, there is a need for developing more effective treatment methods to eliminate dyes from the waste stream at its source. The most effective methods of dye removal from wastewater are adsorption and the use of enzymes. In this study, the removal of Reactive Black 5 (RB5) from aqueous solutions has been studied using silica fume (SF) waste material after its modification with laccase from Russulaceae (Lactarius volemus). Laccase was purified by using saturated precipitate (NH4)2SO4, DEAE-cellulose and immobilized on SF. Batch adsorption experiments have been performed as a function of pH, contact time, temperature, and adsorbent dosage. The optimum results were obtained a...

Experimental study on the nickel (II) removal from aqueous solutions using silica fume with/without apocarbonic anhydrase

Abstract The silica fume is a fine-grain, thin and very high surface area silica. Although the silica fume is a waste material of industrial applications, it has become the most valuable by-product among the pozzolanic materials due to its very active and high pozzolanic property. In this study, the potential use of silica fume in the remediation of polluted heavy metal water to remove nickel ions is presented. For studying metal adsorption, 1 g of silica fume has been taken as adsorbent and then it has been suspended in 50 ml of 3 mmol dm−3 NiCl2, at pH between 3 and 9 and contacted batchwise in a thermostatic (t = 25°C ± 0.1°C) water-bath agitator for 1 h to enable equilibration of the sorbent and solution phases. The nickel concentrations in the samples taken from the silica fume treated aqueous solutions of polluted river water with/without apocarbonic anhydrase (apoCA) and NiCl2 solution have been determined by spectrophotometric method using dithizone. The nickel concentration in the samples of sili...

Regional gas geochemistry in an active tectonic zone, Erzurum Basin, eastern Turkey

Abstract The Karasu Plain is an intermontane sedimentary basin with a Miocene—Quaternary volcanicbasement, andesitic-basalticlava flows and fissure eruptions of basaltic lava. It was filled in the early Quaternary by lacustrine fan-delta deposits, and later by fluvial-alluvial fan deposits. The basin is characterized by NNE-SSW trending sinistral wrench faults on its eastern margin and ENE-WSW trending reverse faults on its southern margin. Both systems of active faults intersect very near to Erzurum, which is considered to be the most likely site for the epicentre of a probable future large earthquake. Regional gas geochemistry has therefore been undertaken adjacent to the city of Erzurum, in order to characterize radon levels over the varied lithologies, examine the potential for geological fault mapping and assess the status of fault activity. Initially,41 sites were sampled and analysed for Rn, CO2, O2 and CH4 in soils along three traverses to the east (8.26km and 4.5km length) and to the west (6.8km length) of Erzurum. During the first investigation, 495 Rn determinations were made from 165 samples at 41 sites over a ten-day period, during which a small earthquake (M=2.95) occurred. Another 211 sites have been subsequently used for Rn investigations including one traverse through the centre of the city. Additionally,water samples were degassed for Rn and soils tested at five key sites around the Erzurum Plain. Radon was readily detected in soils at all sites. Both 222Rn and 220Rn were present at most. Soils over major lithologies gave characteristic signals and, in all traverses, anomalously high values coincided with active faults. Little correlation was found between spring gases (thermal and cold) and adjacent soils. De-gassed spring water Rn values proved highest along the southern margin of the basin and CO2 values were highest along the northern edge.

Effects of waste material–lime additive mixtures on mechanical properties of granular soils

Granular soil was stabilized using different proportions of silica fume–lime and fly ash–lime and compacted at optimum water content. Compaction, compressive strength and California Bearing Ratio tests were undertaken which confirmed that the use of waste materials and lime mixtures improved the strength properties of the crushed granular soils.RésuméDes sols granulaires ont été stabilisés avec différentes proportions de fumées de silice et chaux ou de cendres volantes et chaux et compactés à la teneur eau optimum. Des essais de compaction, de résistance à la compression et de portance CBR ont été réalisés et ont confirmé que l’utilisation de mélanges de sous-produits avec de la chaux augmentait les propriétés de résistance de sols granulaires.

Changes in the chemical composition of an acidic soil treated with marble quarry and marble cutting wastes

Soil acidity greatly affects the availability of plant nutrients. The level of soil acidity can be adjusted by treating the soil with certain additives. The objective of this study was to determine the effect of marble quarry waste (MQW) and marble cutting waste (MCW) on the chemical composition and the acidity of a soil. Marble wastes at different rates were applied to an acid soil. Their effectiveness in neutralizing the soil pH was compared with that of agricultural lime. The changes in the chemical composition of the soil were also evaluated with column test at the end of a 75-day incubation period. The results indicated that the MQW and MCW applications significantly increased the soil pH (from 4.71 up to 6.54), the CaCO3 content (from 0.33% up to 0.75%), and the exchangeable Ca (from 14.79 cmol kg(-1) up to 21.18 cmol kg(-1)) and Na (from 0.57 cmol kg(-1) up to 1.07 cmol kg(-1)) contents, but decreased the exchangeable K (from 0.46 cmol kg(-1) down to 0.28 cmol kg(-1)), the plant-available P (from 25.56 mg L(-1) down to 16.62 mg L(-1)), and the extractable Fe (from 259.43 mg L(-1) down to 55.4 mg L(-1)), Cu (from 1.97 mg L(-1) down to 1.42 mg L(-1)), Mn (from 17.89 mg L(-1) down to 4.61 mg L(-1)) and Zn (from 7.88 mg L(-1) down to 1.56 mg L(-1)) contents. In addition, the Cd (from 0.060 mg L(-1) down to 0.046 mg L(-1)), Ni (from 0.337 mg L(-1) down to 0.092 mg L(-1)) and Pb (from 28.00 mg L(-1) down to 20.08 mg L(-1)) concentrations decreased upon the treatment of the soil with marble wastes.

Removal of copper from copper-contaminated river water and aqueous solutions using Methylobacterium extorquens modified Erzurum clayey soil

Abstract The objective of this study was to investigate the possibility of using natural and bacteria-modified Erzurum clayey soil with Methylobacterium extorquens as an alternative to high cost commercial adsorbent materials for the removal of copper from aqueous solution. The copper concentrations in the samples of the polluted river water and CuCl2 solutions treated by the natural and bacteria-modified Erzurum clayey soil (ECS) have been determined by spectrophotometric method. Firstly, the surface of ECS was modified with M. extorquens and surface functionality was increased. Then, the adsorption of Cu (II) from solution phases was studied with respect to varying metal concentration, pH, and temperature and agitation time. The maximum adsorption of Cu (II) for natural and bacteria-modified Erzurum clayey soil was observed at pH: 5.0. At different copper concentrations, copper adsorption analysis was performed on 1 g using clay soil or modified clay soil. Maximum adsorption of Cu (II) was obtained as 45.7 and 48.1 mg g-1 at initial concentration (50 mg/50 mL) and optimal conditions by natural and bacteria-modified clay soil, respectively. The copper concentration was decreased in the substantial amount of the leachates solutions of natural and bacteria-modified clay soil. Langmuir and Freundlich isotherms were used to describe the adsorption behavior of Cu (II) ions. The results showed that modified clay soil had a high level of adsorption capacity for copper ion. The various thermodynamic parameters such as ΔG°, ΔH° and ΔS° were analyzed to observe the nature of adsorption. The structural properties of the natural and bacteria-modified-ECS have been characterized by SEM, FTIR and XRD techniques. Consequently, it was concluded that the bacteria-modified clay soil could be successfully used for the removal of the copper ions from the aqueous solutions.

Equilibrium studies of copper ion adsorption onto modified kernel of date (Fructus dactylus)

Heavy metal pollution of water is a serious problem because of its toxic effects on the human health and living organism. Therefore, there is a need to develop technologies to remove toxic pollutants found in polluted water. There are different ways to remove the toxic metals from wastewater. Among all treatments proposed, the adsorption process is one of the most promising technologies in water pollution control. Recently, numerous approaches have been studied for the development of cheaper and effective adsorbents. Many low-cost adsorbents, including natural materials, biosorbents and waste materials from industry and agriculture, have been proposed by several researchers. In this study, removal of copper from aqueous solution by using powdered and modified kernel of date (Fructus dactylus) with apocarbonic anhydrase enzyme has been investigated. The operating variables studied were contact time, initial solution pH, initial metal concentration, temperature and adsorbent dosage. The experimental investigation results showed that modified and powdered kernel of date (F. dactylus) has a high level of adsorption capacity for copper ions. The adsorption data were correlated with the Langmuir and Freundlich isotherm models. It was found that the Langmuir and Freundlich isotherms fitted well to the data. The results revealed that copper is considerably adsorbed on modified and powdered kernel of date (F. dactylus). Consequently, it is concluded that the modified and powdered kernel of date (F. dactylus) can be successfully used for the removal of the copper ions from the aqueous solutions.

Removal of Reactive Black 5 from wastewater using natural clinoptilolite modified with apolaccase

Abstract In this study, a clinoptilolite modified with apolaccase was used to adsorb Reactive Black 5 (RB5) dye from aqueous solution using the batch procedure. The influences of pH, contact time, temperature and absorbent dosage on the adsorption were investigated. The optimum adsorption was obtained at pH = 6, contact time = 60 min, temperature = 25°C and adsorbent dosages of 1.62 and 1.59 mg/50 mL per gram of clinoptilolite and of apolaccase-modified clinoptilolite (LMC), respectively). The adsorption experimental data fitted both the Langmuir and Freundlich isotherm models well. In addition, pseudo-first-order and pseudo-second-order kinetics were used to study the kinetics of RB5 dye adsorption onto natural clinoptilolite and LMC. Adsorption appears to follow pseudo-second-order kinetics with a high correlation coefficient. Thermodynamic parameters such as changes in the free energy (ΔGo), enthalpy (ΔHo) and entropy (ΔSo) of adsorption were calculated. The thermodynamic parameters indicate that the adsorption of RB5 dye onto LMC was less spontaneous, feasible and endothermic. The LMC can be used as an alternative low-cost adsorbent for the dye removal from aqueous solutions.