Absorption of toluene vapors from atmospheric air through surface absorption of adsorbents based on gas phase extraction was obtained. In experimental study, through pilot simulator, toluene vapors absorption and absorbents efficiency in the dynamic and static system was examined by nano graphene and graphene oxide (NG and GO).The effect of different parameters on toluene absorption by NG and GO such as: absorption capacity, temperature desorption, contact time and repeatability, the amount of sorbents and recovery adsorption were investigated. According to discovered findings, capacity and efficiency of absorption by absorbents depend to kind of absorbent, mass of absorbent, toluene density, temperature, air flow rate and contact time. The toluene concentration in air was determined by gas chromatography spectrometer with flame ionization detector (GC-FID). The mean of absorption recovery (AR) and the absorption capacity (AC) for nano graphene absorbent was higher than graphene oxide, respectively (ARNG: 97.3% > ARGO: 23.5%; ACNG: 285.2 mg/g > ACNGO: 67.3 mg/g)

Sorption isotherms of two acid dyes, Blue 127 and Green 25 on nylon 6 fibers were studied at 90 and 98C, respectively. A remarkable deviation from Langmuir isotherm was obtained for both dyes. Performance of Dual-Mode sorption model which consists of Langmuir mechanism and Nernst model was tested. Dual-Mode fitting was appeared to be in good agreement with the experimental data rather than Langmuir. In addition, the sorption capacity of fiber from measuring the amino end-group content and that calculated from Langmuir isotherm was compared. The results confirmed that the adsorption is not limited only to the sitting mechanism and there are the other sites involving in the adsorption. Studying the temperature effect on Dual-Model isotherm showed the total adsorption capacity of fiber is decreased by increasing the temperature. However the most part of total sorption was still followed as Langmuir isotherm. J

Conversion of agricultural wastes to valuable products is one of the sustainable method to prevent air pollution thet arises from biomass open burning. One of these new and valuable products are lignocellulosic aerogels, which due to their superior characteristics, such porous structure and large surface area can be used for removal of various pollutants such as dye. In this study, lignocellulosic aerogel obtained from rice straw were used to remove the Acid Orange 7 (AO7) from water and the effect of absorption process parameters on adsorption were investigated. The results demonstrated that the efficiency of adsorption greatly influenced by solution pH and temperature. For various concentrations of dye, the equilibrium was reached at 120 minutes. Isotherm data were well adapted to the Langmuir model and maximum adsorption capacity estimated from linear Langmuir was 52.1 mg/g that was approximately twice of the rice straw adsorption capacity. The kinetics results well interpreted by pseudo second order mode, indicating chemisorption as the rate-limiting step which correspond to the interactions between the active sites of aerogel surface and the functional groups of dyes.

Sorption hysteresis in soil constituents has important environmental implications such as pollutant transport and bioavailability. This research was carried out to study sorption reversibility of cadmium (Cd) on natural zeolite. Sorption isotherms were derived by sorption of Cd (П) from solutions containing different concentrations of Cd in the range of 1 to 10 mg L-1 using a 24h batch equilibration experiment. Desorption of Cd(II) was studied with the clay samples initially treated with the metal loadings of 50 and 100% maximum sorption capacity (SCmax) during the sorption study. Sorption isotherms of Cd were well described by the Freundlich and Coble-Korrigan models (R2=0.96). Desorption isotherms of Cd from zeolite showed little deviation from sorption data indicating reversible sorption. On the other hand, the results revealed no hysteresis. The average amount of 71.75 % of the initially sorbed Cd was desorbed from zeolite after five successive desorption steps. Release of such a relatively high proportion of sorbed Cd indicates that zeolite is an effective sorbent for the repeated purification of polluted water and wastewater.

This project studies the absorption and removal of copper cations from aqueous solutions by starch-poly (acry-lamide-co-acrylic acid) / graphene oxide hydrogel bio-nanocomposites. The bio-nanocomposite hydrogel was obtained from a radical polymerization of the starch biopolymer with vinyl acrylamide (Am) and acrylic acid (AA) monomers with N,N-methylenebisacrylamide (MBA) in the presence of graphene oxide nanosheets (GO). The bio-nanocomposites were investigated by XRD, FT-IR, FE-SEM, TEM and TGA techniques. The effect of pH on adsorption, effects of time on adsorption, the initial concentration of copper ions and effect of temperature on the adsorption process on copper ions were investigated. The results which obtained from the experiments on the removal and absorption of copper ions were shown the maximum adsorption at pH =5 / 5, the adsorption increased by increasing the time, the equilibrium adsorption process flowed by Langmuir isotherm model and according to thermodynamic parameters, the adsorption of Cu2+ on bio-nanocomposite hydrogels occurred endothermic process and spontaneously, respectively. Also, the amount of adsorption increases proportionally to the amount of GO. Additionally, because of the enthalpy of absorption between 20-80 (KJ / mol), as a result, the process of removal is an electrostatic process

Boron (B) is an important plant essential micronutrient whose availability is influenced by many soil factors. Adsorption–desorption processes play a major role in governing the solubility of boron in soil solution and، consequently، its availability to growing plants. To assess the effect of sodium adsorption ratio (SAR) on availability of B، adsorption of B was investigated in a sampled calcareous soils that had low levels of electrical conductivity. Boron adsorption experiments were carried out on the soil in batch systems to determine adsorption isotherms (amount of B adsorbed as a function of equilibrium solution B concentrations). To determine the quantity of adsorbed B، 5 g of soil were shaken for 12 h، in propylene 50 mL tubes، with 20 mL of B solution (0، 2، 5، 8، 10، 15، 20 mg L-1) (as boric acid) at ionic strengths of 0. 12 M (prepared by NaC1، CaC12. 2H2O، MgCl2. 6H2O) at five SAR levels (2، 5، 10، 15، 20). The reaction temperature was 25◦C. The suspension was centrifuged، filtered، and a sample was removed and B was determined by Azomethine-H spectrophotometric method (at a wavelength of 420 nm). Soil B adsorption was calculated by subtracting B in the solution after filtration from the added boron. Langmuir، Freundlich، linear Freundlich isotherms fitted well to the adsorbed data based on R2 and SEE. However، the fit of the Langmuir equation was closer to the experimental data. At different SAR values، the soil exhibited different adsorption behaviors. The effect of SAR on the boron adsorption was greater at high concentrations and the highest adsorption was at SAR 15، except for SAR 20 that had the lowest B adsorption. Effect of sodium adsorption ratio on adsorption of boron may be due to the dissociation of boric acid to borate anion and changes in the thickness of the diffuse double layer.

Organic hydrocarbons as a result of carcinogenesis and mutation caused many concerns. In this research, straw and chalk absorber was used as an organic adsorbent to remove oil pollution from wastewater. The adsorption experiments were performed discontinuously using oil-containing laboratory solutions. Optimum adsorption conditions were obtained by changing the factors affecting adsorption including pH, initial concentration of contaminant, contact time and adsorbent amount on adsorption at different levels, the oil absorption was determined by weighting method. Ultimately, the use of adsorbent for laboratory wastewater was studied. The highest absorbent efficiency at the time of equilibrium was observed for absorbing oil in 15 minutes a bout 28.85% absorbance, which did not have a significant difference with other contact times, which could be due to low contact time and the lowest value was observed with a significant difference of 3 minutes about 17.82% absorption, with the absorption rate being most significant in relation to the time of low, due to increased absorption time Increases. The highest rate of straw absorption was observed in pH = 7, which did not have a significant difference with other pH about36.95% absorption and the lowest percentage of adsorption was observed at pH = 9, which had no significant difference with other pHs (19.09% absorption; P

Water pollution with oil compounds is one of the most important environmental issues in oil-rich countries, as it can have adverse effects on human health and the environment. It is absolutely essential to use optimized and efficient methods for treatment of oil-containing wastes. There are several strategies to remove oil pollution and its derivatives. In this research, rice's peel adsorbent was used as an organic adsorbent to remove oil pollution from wastewater. Initially, the chemical composition of rice peel was determined with using FT-IR analysis, then adsorption tests were conducted discontinuously using laboratory solutions containing oil to determine optimum adsorption conditions by adjustment of effective factors such as pH, initial concentration, exposure time, and adsorbent amount, and the amount of oil adsorption was determined using weight method. Ultimately, the use of adsorbent for laboratory wastewater was studied. The highest adsorbent efficiency was observed for absorbing oil during 15 minutes, which had a significant difference with other contact time (79.77% absorption, P <0.05) and the lowest value by difference significance was observed in 3 minutes (65.93% absorption). The highest amount of adsorption by rice peeling was observed at pH = 5 and pH = 3, which did not show significant differences with other pHs (76.57% and 75.34%, respectively, P < 0.05) and the lowest adsorption was observed at pH = 9, which had no significant difference with other pH (58.93%, P <0.05). The effect of rice peel absorbent values in 1.5 g/l was significantly higher than other amount of adsorbents (84.1% absorption, P <0.05) and the lowest percentage of adsorption was significantly different from other values in 0.25 g / liter was observed (62.58%; 05.05 P). Isotherm fitting of surface adsorption showed that oil adsorption by rice peel follows the Freudlich model (R2 = 0.98). Therefore, it can be concluded that rice peel adsorbent has a high efficiency in adsorbing oil from wastewater and can be used in the treatment of industrial wastewater.

Aim and The importance of effective parameters on b iosorption of Cu and Mn ions from Sarcheshme Copper Mine Acid Mine Drainage (AMD) was investigated using regression analysis. Bacillus Thuringiensis was isolated from Sarcheshme AMD water and sorption parameters of that AMD water were investigated. Correlation between amount of biosorbent and amount of Cu removed (0. 99) was greater than the correlation between amount of biosorbent and Mn removed (0. 98) from wastewater. Furthermore، increasing pH increased Cu and Mn ions removal up to 19 and 9 times، respectively. It was also observed that increasing contact time raised the Cu and Mn uptake 4. 83 and 1. 5 times، respectively. Results showed that parameters like amount of biosorbent، pH، temperature and contact time have the most impact on amount of biosorption respectively and variation of effective parameters have more effects on Cu removal from wastewater.

This study examined the adsorption of lead (Pb) ions from aqueous solution onto shrimp shell. Several important parameters influencing the adsorption of Pb(II) ions such as initial pH, equilibrium time, and different initial concentration of Pb(II) ions were evaluated. The results indicated that the pseudo-second-order kinetic model could describe the kinetics of Pb adsorption by the adsorbent. With increasing Pb concentrations from 100 to 1000 mgL-1, the amount of Pb adsorbed by shrimp shell increased from 9 mg g-1 to 90.2 mg g-1. Increasing suspension pH from 4 to 7, enhanced adsorption of Pb. Further increase in pH from 7 to 10 resulted in decreasing of adsorption of the metal ion. The average adsorption of Pb by the adsorbent at pH 6 and 7 was more than 95 percent. The Sips and Freundlich models well described the adsorption of Pb isotherms data. Infrared spectrum analysis of adsorbent before and after adsorption of Pb showed that the N atoms of the amine functional groups played a major role in shrimp shell for adsorption of Pb.