Licorice residue and Pistachio-nut shell mixture: A promising precursor for activated carbon

T. Kaghazchi,N. Asasian Kolur,M. Soleimani 한국공업화학회 2010 Journal of Industrial and Engineering Chemistry Vol.16 No.3

As a continuation of previous research concerning preparation of activated carbon from agricultural byproducts,applying a mixture of two kinds of lignocellulosic by-products with complementary properties as the parent material is investigated. Two kinds of activated carbons are prepared by chemical activation of the parent mixture – including residues of licorice and pistachio-nut shells – with H3PO4and ZnCl2 solutions, separately. The produced activated carbons have the surface areas comparable to the commercial ones. The lower ash content, higher bulk density and surface area of mix-based activated carbons in comparison with licorice-based ones, and also the highest mercury adsorption capacity of the mix-based ones confirm that it would be possible to modify the properties of an activated carbon using several complementary raw materials. The comparison of mercury adsorption capacities among mixedbased and the commercial activated carbons reveals that mix-based ones are effective and economical adsorbents for industrial wastewater treatment. 2010 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.

Modification of activated carbon using a NOx-containing gaseous by-product for enhanced Hg(II) removal from aqueous phase

Tahereh Kaghazchi,Hadi ShamsiJazeyi 한국공업화학회 2011 Journal of Industrial and Engineering Chemistry Vol.17 No.3

In this study, activated carbon was treated using a gaseous by-product produced by the reaction of nitric acid and activated carbon. To determine the effectiveness of this treatment for enhancing the Hg(II)removal capacity of activated carbons, several batch experiments have been conducted for two different commercial activated carbons at different pH values, temperatures, and initial concentrations. In addition, Iodine number, BET surface area, total and micro-pore volume, as well as pHpzc amounts of treated and untreated samples were compared to determine the effects of this treatment on the porous structure and surface charge of activated carbons. After this modification, a decrease in porous characteristic and an increase in the surface acidity of activated carbons were observed. Hg(II) speciation for experimental conditions in this work showed that molecular species including HgCl2, HgClOH, and Hg(OH)2 are generally present in the solution. Additionally, thermodynamic calculations indicated that the Hg(II) removal using the modified activated carbons in this work is an endothermic process with increase in the entropy of the system. The positive entropy change was described by the chemisorption mechanisms during which some released species from the surface into the aqueous phase may increase the degree of freedom.

Water and mercaptan adsorption on 13X zeolite in natural gas purification process

Tahereh Kaghazchi,Babak Shirani,Masoud Beheshti 한국화학공학회 2010 Korean Journal of Chemical Engineering Vol.27 No.1

The aim of this work is to model the adsorption process used for mercaptan and water removal from natural gas. Three fixed beds containing Zeolite molecular sieve type 13X, are used in this plant. In this operation, two beds are in process for adsorption purposes and the other one is regenerated simultaneously. This system is also operated under isothermal condition. In modeling of this process, rate of adsorption is approximated by linear driving force (LDF)expression, and the extended Langmuir isotherm is used to describe adsorption equilibrium. The set of partial differential equations of dynamic model is solved by Crank-Nicolson method. The effect of equations of state is also studied and the best equation fitting the industrial data is selected. Also, concentration profile is presented versus bed length at various times. The influences of pressure, inlet concentration and bed height on the breakthrough time are also investigated.

Elimination of mercury by adsorption onto activated carbon prepared from the biomass material

Neda Asasian,Mansooreh Soleimani,Tahereh Kaghazchi 한국공업화학회 2012 Journal of Industrial and Engineering Chemistry Vol.18 No.1

Following the previous work (Kaghazchi et al., 2010 [11]), dealing with applying a combination of two kinds of agricultural wastes to produce a new adsorbent, this study is dedicated to investigate the details of mercury adsorption process from aquatic medium by this adsorbent. So the Mix-ZC activated carbon (the sample prepared by chemical activation of a mixture of pistachio-nut shells and licorice residues impregnated with zinc chloride) was selected for doing a series of batch adsorption experiments on it. Equilibrium isotherms, such as Freundlich, Langmuir, Dubinin–Redushkevich and Temkin have been tested. Kinetic studies based on Lagergren first-order, pseudo-second-order rate expressions and intraparticle diffusion studies have been done. The mechanisms of mercury adsorption onto this adsorbent under the operating conditions were also studied.

The investigation of the potential of activated hard shell of apricot stones as gold adsorbents

Mansooreh Soleimani,Tahereh Kaghazchi 한국공업화학회 2008 Journal of Industrial and Engineering Chemistry Vol.14 No.1

Activated carbon is the most widely used adsorbent for the recovery of metal ions from dilute solutions. In this work the potential of activatedcarbon produced from hard shell of Iranian apricot stones for the gold recovery from electro-plating wastewater was investigated. The effect ofparameters such as doseof activated carbon, particle size ofactivated carbon, pH and agitationspeed of mixingon thegoldadsorption was studied.The results showed that under the optimum operating conditions, more than 98% of gold was adsorbed onto activated carbon after only 3 h. Inaddition, the adsorbed gold could be eluted from this carbon by improved stripping method. The process involves contact of gold laden activatedcarbon with a strong base at ambient temperatures followed by elution with an aqueous solution containing an organic solvent. It was found thatactivatedcarbonproducedfromhardshellofapricotstoneshavehighpotentialtobeusedinsteadofimportedcommercialactivatedcarbonsingoldadsorption processes.# 2007 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.

Investigation of nitric acid treatment of activated carbon for enhanced aqueous mercury removal

Hadi ShamsiJazeyi,Tahereh Kaghazchi 한국공업화학회 2010 Journal of Industrial and Engineering Chemistry Vol.16 No.5

In the present work, Hg(II) adsorption of a commercial activated carbon with and without nitric acid treatment was compared in a batch system. Iodine adsorption test and nitrogen adsorption and desorption experiments were carried out to investigate the changes in porous characteristics during acid treatment. Although the results for iodine adsorption of two samples were approximately similar, the increase in porous characteristics during acid treatment was determined bymicropore volume and total pore volume of treated and untreated samples. To evaluate the effects of acid treatment on the surface functional groups, FTIR analysis for both types of activated carbons was performed, and showed oxidized surface for treated sample. Furthermore, composition of the gaseous by-product resulted from this treatment has been qualitatively analyzed using a FTIR device. Consequently, NO, NO2, N2O4, N2O, CO,and CO2 were detected. Kinetic and equilibriumadsorption studies were performed considering effective parameters, including contact time, initial pH, and initial concentration. It can be seen that nitric acid treatment of activated carbon has enhanced Hg(II) adsorption capacity. Moreover, kinetic studies showed faster adsorption rate for treated activated carbon through changes in external surface rather than internal. 2010 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.

A review on olefin/paraffin separation using reversible chemical complexation technology

Maryam Azhin,Mohammad Rahmani,Tahereh Kaghazchi 한국공업화학회 2008 Journal of Industrial and Engineering Chemistry Vol.14 No.5

In the present work, the facilitated transport membrane (FTMS) technology used in separation of olefins from paraffins is reviewed. Primary attentions are given to basic fundamentals, advantages and methods of facilitated transport membrane technology. The general mechanisms by which the facilitated transport proceeds under various conditions are described. The effects of different parameters on the degree of facilitated factor, permeance, and selectivity in the FTMs are thoroughly discussed. The performance of the membranes and its current application related with the polymer, solvent, and carrier structure developing during membrane preparation are also considered. A number of potential applications of the FTMs in a variety of modules can be added and optimized in a process design to achieve the desired separation are highlighted in this review. Finally, some reviews have been conducted for the modeling as well as the numerical solution to the governing system of equations.

Optimization of parameters for competitive adsorption of heavy metal ions (Pb+2, Ni+2, Cd+2) onto activated carbon

Mohammad Kavand,Mansooreh Soleimani,Tahereh Kaghazchi 한국화학공학회 2014 Korean Journal of Chemical Engineering Vol.31 No.4

This study investigates optimization of various competitive adsorption parameters for removal of Cd(II),Ni(II) and Pb(II) from aqueous solutions by commercial activated carbon (AC) using the Taguchi method. Adsorptionparameters such as initial metal concentration of each metal ion (C0, i), initial pH (pH0), adsorbent dosage (m) and contacttime (t) in batch technique were studied to observe their effects on the total adsorption capacity of metals onto activatedcarbon (qtot). The adsorbent dosage has been found to be the most significant parameter. Interactions between C0, Cd×C0, Ni, C0, Cd×C0, Pb and C0, Ni×C0, Pb have been considered for simultaneous metal ions adsorption. The optimum conditionfor adsorption of metal ions were obtained with C0, i=100 mg L−1, pH0=7, m=2 g L−1 and t=80min. Finally, experimentalresults showed that a multi-staged adsorptive treatment would be necessary to reach the minimal discharge standardsof metal ions in the effluent.

Receptor activator of nuclear factor kappa-B gene polymorphisms in Iranian periodontitis and peri-implantitis patients

Kadkhodazadeh, Mahdi,Baghani, Zahra,Ebadian, Ahmad Reza,Kaghazchi, Zahra,Amid, Reza Korean Academy of Periodontology 2014 Journal of Periodontal & Implant Science Vol.44 No.3

Purpose: Peri-implantitis and periodontitis are inflammatory and infectious diseases of implant and tooth-supporting tissues. Recently, the role of gene polymorphisms of immune response components in the relevant pathogenesis has been investigated. The present study was the first to evaluate the relationship between two known single nucleotide polymorphisms (SNPs) of the receptor activator of nuclear factor kappa-${\beta}$ (RANK) gene (rs3018362 and rs35211496) in chronic periodontitis and peri-implantitis patients in an Iranian population. Methods: Eighty-one periodontally healthy patients, 38 patients with peri-implantitis, and 74 patients with chronic periodontitis were enrolled in this study. DNA was extracted from blood arm vein samples by using Miller's salting out technique according to the manufacturer's instructions given in the extraction kit. The concentration of DNA samples was measured using a spectrophotometer. The genetic polymorphisms of the RANK gene were evaluated using a competitive allele specific polymerase chain reaction (KBioscience allele specific PCR) technique. Differences in the frequencies of genotypes and alleles in the diseased and healthy groups were analyzed using chi-squared statistical tests (P<0.05). Results: Analysis of rs35211496 revealed statistically significant differences in the expression of the TT, TC, and CC genotypes among the three groups (P=0.00). No statistically significant difference was detected in this respect between the control group and the chronic periodontitis group. The expression of the GG, GA, and AA genotypes and allele frequencies (rs3018362) showed no statistically significant difference among the three groups (P=0.21). Conclusions: The results of this study indicate that the CC genotype of the rs35211496 RANK gene polymorphism was significantly associated with peri-implantitis and may be considered a genetic determinant for peri-implantitis, but this needs to be confirmed by further studies in other populations.

Understanding on the structural and electrochemical performance of orthorhombic sodium manganese oxides

Choi, Ji Ung,Yoon, Chong Seung,Zhang, Qian,Kaghazchi, Payam,Jung, Young Hwa,Lee, Kug-Seung,Ahn, Do-Cheon,Sun, Yang-Kook,Myung, Seung-Taek The Royal Society of Chemistry 2019 Journal of materials chemistry. A, Materials for e Vol.7 No.1

<P>We investigate the orthorhombic Na0.67[NixMn1−x]O2 (<I>x</I> = 0 and 0.05) cathode materials that provide high capacity for prolonged cycles. X-ray absorption studies revealed that the redox activity of the Mn<SUP>3+/4+</SUP> and Ni<SUP>2+/3+</SUP> pairs is effective in suppressing the Jahn-Teller effect of Mn<SUP>3+</SUP> ions because of the network with Ni<SUP>2+</SUP> ions. This effect influenced the smooth voltage variations in the voltage profile for Na0.67[Ni0.05Mn0.95]O2, whereas several complicated voltage plateaus associated with the first-order phase transition were noticed in Na0.67MnO2. <I>Operando</I> synchrotron X-ray diffraction and transmission microscopy studies confirmed the simplicity of the phase transition for Na0.67[Ni0.05Mn0.95]O2 due to suppression of the Jahn-Teller effect of Mn<SUP>3+</SUP> in the oxide lattice. These findings, along with the capacity retention during prolonged cycling and the acceptable thermal properties, make high-capacity sodium-ion batteries feasible, inexpensive, and safe for energy storage application.</P>