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Acid Red 57 (AR57) has been successfully removed from aqueous solution by adsorption on our synthesized mesoporous carbon-coated monolith (MCCM). For the first time, a powerful artificial neural network (ANN) model has been developed to predict the removal efficiency of AR57 on MCCM. Three critical parameters in adsorption systems, that is, solution’s initial pH, initial dye concentration, and contact time were incorporated in the ANN model in order to optimize the observed adsorption process. Langmuir and Freundlich adsorption models were then fitted to the adsorption data to estimate the adsorption capacity. It was concluded that Langmuir isotherm was best-fitted to the data showing a maximum monolayer adsorption capacity of 1,162.7 mg/g. The pseudo-first-order and pseudo-second-order kinetic models were subsequently tested to evaluate the kinetics of the adsorption process. It was revealed that the adsorption kinetics could be better represented by the pseudo-second-order model. A comparison was finally drawn between ANN and pseudo-second-order kinetic models. Based on the error analyses and determination of coefficients, ANN was the more appropriate model to describe the studied adsorption process. [ABSTRACT FROM PUBLISHER]

Abstract: Mesoporous carbon coated monolith prepared from furfuryl alcohol by the dip-coating method was utilized as an adsorbent for adsorption of β-carotene from crude palm oil. The effect of temperature on the adsorption was investigated by batch adsorption experiments. The adsorption quantity increased with increasing temperature. The adsorption was performed using two different solvents, isopropyl alcohol and n-hexane. The maximum adsorption capacity of β-carotene was 62.118mg/g for isopropyl alcohol at 50°C. The experimental results were fitted using the Langmuir and Freundlich isotherms. The Langmuir described the adsorption process better. The negative values of Gibbs free energy change suggested that the adsorption was a spontaneous process. The positive values of heat of enthalpy and entropy change confirmed the endothermic nature of the adsorption. [ABSTRACT FROM AUTHOR]

Abstract: Arsenic contamination in water, especially groundwater, has been recognized as a major problem of catastrophic proportions. The toxicology and health hazard also has been reported for many years. Because of the recognition that arsenic at low concentrations in drinking water causes severe health effects, the technologies of arsenic removal that have become increasing important. The current regulation of drinking water standard is become more stringent and requires arsenic content to be reduced to a few parts per billion. There are several treatment methods capable of this level of performance ― membranes, coagulation, anion exchange, disposable iron media, softening etc. Treatment cost, operational complexity of the technology, skill required to operate the technology and disposal of arsenic bearing treatment residual are factors should be considered before treatment method selection. This paper aims to review briefly arsenic toxicology and hazards and also the previous and current available technologies that have been reported in arsenic removal. Residual generation and disposal after treatment will also be discussed. [Copyright &y& Elsevier]

Abstract: The rate of dye adsorption from aqueous effluents onto palm kernel shell (PKS) activated carbon has been studied experimentally using the batch adsorption method. The adsorption rates of methylene blue on PKS for systems of different initial dye concentrations are modeled using a film-pore-concentration dependent surface diffusion (FPCDSD) model. The FPCDSD model is sufficiently general and can be reduced easily to describe other simplified models. Using the FPCDSD model, only a single set of mass transfer parameters is required to describe the methylene blue/PKS system for different initial concentrations. A different set of mass transfer parameters are needed to obtain the best fitting if the pore diffusion is not included in the model. [Copyright &y& Elsevier]

Abstract: Carbon coated monolith (CCM) was chemically modified by treating with nitric acid. The acid modified carbon coated monolith (ACCM) was then characterized by using various techniques. Two folds increase in acidic sites was observed on ACCM compared to CCM. Surface studies showed mesoporous nature of ACCM. A decrease in ACCM surface area and an increase in pore volume observed after the modification. The ATR-FT-IR studies showed increase in carboxylic groups on ACCM confirming CCM oxidation by nitric acid. The pH studies showed optimum adsorption (88mg/g) at pH 6 which is very near to pHPZC of ACCM. Contact time studies showed equilibration time in between 4320 and 4560min for initial MO concentration range 0.05–0.6g/L. Comparatively 53% higher MO adsorption was observed on ACCM than CCM under similar experimental conditions. Freundlich model applicability confirms multilayer MO adsorption on ACCM surface. Pseudo-second-order kinetics model was fitted best to the experimental data revealing chemical nature of adsorption process. The adsorption process is endothermic and spontaneous in nature. Desorption studies showed optimum MO recovery (73%) when 1N NaOH was used as an eluent. [Copyright &y& Elsevier]

Abstract: The cordierite monolith was successfully modified to carbonaceous material termed as carbon coated monolith (CCM). Surface studies showed about 65% of the total pore volume falls in mesopore range with acidic functionality dominating over the surface. Batch adsorption experiments were carried out to study the applicability of CCM for the removal of methyl orange (MO) from aqueous solution. Different parameters such as effect of MO concentration, contact time, initial pH, regeneration and desorption potential of CCM were studied. Optimum adsorption of MO on CCM was observed at pH 6 (27.2mg/g). The increase in initial MO concentration from 50 to 500mg/L leads to increase in adsorption capacity from 15.99 to 88.5mg/g. The observed equilibration time ranged in between 5000 and 5800min. Linear and non-linear isotherm studies showed better applicability of Freundlich model. Kinetics studies showed better fitting for pseudo-second-order model. The Weber and Morris model showed multi-linearity indicating two or more steps were involved to describe the adsorption process. Desorption studies showed maximum recovery of MO when alkaline NaOH solution was used as an eluent. The regeneration studies showed decrease in adsorption capacity from 47.93 to 23.76mg/g after three cycles. [Copyright &y& Elsevier]