Low cost adsorbent are prepared from activated sugarcane bagasse (ASB), activated waste paper (AWP), and activated Delonix regia Fruit Pod (ADRF)which act as a useful adsorbent for the removal of methylene blue from aqueous phase. The study was carried out using batch experiments with synthetic wastewater having a methylene blue concentration. The effects of contact time were investigated and compared for all the three adsorbents. The adsorption process reached equilibrium within 120min of contact time almost for all adsorbent. Comparative study of contact time indicates that sugarcane bagasse adsorbed at faster rate and adsorbed the maximum. The Freundlich, Langmuir, models were used for mathematical description of the adsorption equilibrium, and it was found that the experimental data fitted very well to the Langmuir isotherm for all the three adsorbent. Batch adsorption studies, based on the assumption of a pseudo-first-order, pseudo-second-order, showed that the kinetic data followed closely a pseudo-second-order rather than a pseudo-first-order mechanism.
This book provides the usefulness of date palm as adsorbent in the removal of unwanted pollutants such as dyes, heavy metals, organic compounds and pesticides. Many studies on adsorption properties of various low cost adsorbent such as agricultural waste and activated carbon based on agricultural wastes have been reported in recent years. Studies have shown that date palm is the most promising adsorbents for removing pollutants from waste water.
Present study deals with the removal of Congo red through adsorption from its aqueous solution on Raphanus sativus peel. The basic purpose of this study is to evaluate low cost adsorbent for dye removal. Being carcinogen Congo red is hazardous and toxic. Batch wise removal were executed in order to estimate the effects of a various experimental parameters like Mesh size, adsorbent dose, contact time, temperature, agitation speed and pH. Adsorbent was treated with 0.1M HCl and 0.1M NaOH. Similar experimental parameters were performed for these acid and base treated adsorbents. Comparative study revealed that acid treated is the adsorbent. However, pH factor showed maximum percentage of adsorption in U.T.B. Langmuir and Freundlich Isothermal model were used to explain the equilibrium for these adsorption processes. Study revealed that adsorption followed Langmuir model for A.T.B and B.T.B whereas freundlich model for U.T.B. The adsorption capacity was 0.06, 0.24 and 0.12 mg/g for untreated, acid and base treated respectively. The maximum capacity observed for A.T.B in Langmuir isotherm. So, acid treated Raphanus Sativus peel are potential adsorbents for Congo red removal.
Removal of organic and inorganic pollutants from wastewater by adsorption on activated carbon and synthetic resins has been widely studied. Though activated carbon is an ideal adsorbent for organic matter due to its organophillic character, high cost of preparation and regeneration is a limiting factor for their large-scale use in wastewater treatment. This has prompted the use of many novel materials as adsorbents. The present work was aimed at developing a low cost adsorbent from the mature leaves of the Neem (Azadirachta indica)tree. The objectives were to convert dry, mature Neem leaves into a powder (Neem Leaf Powder, NLP), characterize the adsorbent (NLP) by spectroscopic and other methods, test the effectiveness of NLP as an adsorbent for removal of micro-pollutants such as dyes (methylene blue, Congo red, brilliant green) and metal ions (Cd(II), Cr(VI) and Pb(II)) from an aqueous medium, and determine the influence of various factors such as concentration, pH, temperature, and agitation time, etc., on adsorption. Both batch and column adsorption processes were applied with significant achievements.
In this present study, adsorption of Cr (VI) ions on tamarind tree bark adsorbent has been studied through using batch adsorption techniques. The main objectives of this study are to 1) investigate the chromium adsorption from aqueous solution by tamarind tree bark, 2) study the influence of pH, contact time, adsorbent dose, particle size and initial chromium concentration on adsorption process and 3) determine appropriate adsorption isotherm and kinetics parameters of Cr (VI) adsorption on tamarind tree bark. In this present study the parameter like pH, contact time, adsorbent dose and initial chromium concentration were determined with the help of synthetic chromium sample. Also with the help of electroplating industrial wastewater sample, the parameters adsorbent dose, contact time and particle size were determined.The results of this study show that higher Cr (VI) adsorption was observed at lower pH, and maximum Cr (VI) removal 97% obtained at pH value 1.0 with 30 minutes contact time, adsorbent dose 3.75g/l of particle size 150µ and 5mg/l initial Cr (VI) concentration.
Water pollution is a serious threat to mankind in the present scenario and, hence, many techniques are in use for water treatment. Out of them the adsorption is a commonly used method as it is simple, fast, and universal in nature. Typically, activated carbon is used as a perfect adsorbent for wastewater treatment but it is overpriced and requires regeneration. The regenerated carbon exhibits lower adsorption capacity with further management problem of the effluent obtained from its regeneration. These facts have grown interest in the search for solid waste based low cost alternatives of activated carbon that can be used for water pollutant removal. This book tells how (i) to develop low cost adsorbents from waste materials (ii) to remove toxic pollutants by using developed low cost adsorbents (iii) to optimize adsorption parameters for the maximum removal of pollutants by using developed low cost adsorbent through batch process (iv) to transfer batch adsorption conditions to the column studies; to evaluate the feasibility of the developed adsorption system in real samples (v) to ascertain adsorption mechanism for applying the developed adsorption system effectively & practically.
Synthesis, characterization and intercalation of Zeolite A from Nigerian Ahoko kaolin for adsorption studies of Methylene blue (MB)were studied. The Zeolite A was synthesized from Nigerian Ahoko kaolin (NAK) using hydrothermal technique and was intercalated by hexamethyltetraamine (HMTA). The synthesized zeolite A (SZA) and intercalated zeolite A (IZA) were characterized using X- Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Braunauer Emmet Teller (BET) and Fourier Transform Infrared spectroscopy (FT-IR) analyses.The XRD reveal zeolite A peaks including several peaks depicting presence of minerals like quartz, mica, calcium and iron.The surface area of SZA and IZA were found to be 21.11m2/g and 21.47m2/g, respectively based on BET analysis. The effects of initial concentration, adsorbent dosage, pH and temperature with contact time were studied for SZA and IZA to examine their performance as an adsorbent. The adsorption rates increased with increase pH,temperature, initial concentration and adsorbent dosage for both SZA & IZA. The intercalation also positively increases the adsorption capacity of the parent material.
Phosphorus (P) is growth limiting nutrient and deficient in most soils of the world. Research was conducted on five soil series of Pakistan differing in soil properties. Phosphorus adsorption isotherms were developed and fitted to Langmuir and Freundlich equations to describe P adsorption process. The study suggests that the oxides of iron and aluminum are the main adsorbent at low P concentration, normally applied in agricultural soils and soil CaCO3 play role at high P level. This book is recommended for soil science community working on P chemistry.
Removal of heavy metal ions from water and wastewater has became more important due rapid industrialization. However among all the conventional methods application of adsorption for heavy metal removal gained more importance. However application of activated carbon as adsorbent became more popular, however due to cost effectiveness its application been limited. Low-cost adsorbents from agricultural bio waste were observed as novel materials for metal removal. This book includes application of agro-biomass as adsorbent for metal removal. The book consists of brief introduction of water pollution and methods for removal of metal ions and adsorption mechanism. Also several empirical models have been adopted to analyze the equilibrium data. Kinetics and isotherm have been studied. This book is very useful for scientists, engineers and researcher who are working in the areas of adsorption and biosorption.
The eucalyptus lenceolata wood was collected and converted into carbon. The carbon was then characterized by BET surface area, scanning electron microscopy (SEM), FTIR and energy dispersive spectroscopy (EDS) techniques. Adsorption of some dyes (basic green 5 and Methylen blue) were studied on the treated and raw sample of carbon powder by kinetics adsorption at different adsorption temperatures. Linear models were used for analysis adsorption kinetics studies. From adsorption kinetic data the thermodynamic parameters were calculated for finding the adsorption mechanism. The results show that the adsorption process is spontaneous process. The negative value of entropy shows that the molecules on the surface of adsorbent take an oriented position on the adsorbent surface. All models were found best fit for the adsorption data.
Methylene Blue (MB) is one of the major contaminants found in water sources. Therefore, this study emphasizes the importance of the removal of this organic pollutant. Silica based metals incorporated catalysts were synthesized via sol-gel method and were characterized by several physico-chemical techiques such as FT-IR, XRD, Nitrogen Adsorption- Desorption, TGA, SEM-EDX, TEM, AAS, and Photoluminescence. The metals incorporated were titania, ceria and silver oxide. The presence of these metals were proven by the XRD, SEM-EDX and AAS analysis. The adsorption capability of Rice Husk Silica (RHS) increased when metal ions are incorporated. The photocatalytic capability of these metals incorporated RHS catalysts seemed to have rivaled that of commercially synthesized pure titania (99% anatase phase)powder which is currently being used for the photocatalysis study of organic pollutants.
Utilization of biological waste in treatment of industrial effluents is an emerging field of research. In present context of waste management, bio-adsorbent based techniques are well-known as an eco-friendly approach, for cleaning up various industrial effluents. The efficiency of water hyacinth, as low cost bio-adsorbent has been investigated for removal of lead ions from aqueous solution. Equilibrium behavior of this adsorbent was investigated by performing batch adsorption experiments to study the effect of the major parameters such as contact time, initial concentration of metal ion and adsorbent dose, etc. Response surface methodology was applied to predict the optimal condition of lead ion removal. The correlation of the operating variables and the response based on face centered central composite design are fitted to quadratic polynomial equation. The quadratic term of initial metal ion concentration showed significant influence on the extent of removal. This work showed the potential of the water hyacinth as bio-adsorbent for removal of lead ions from paint industry effluent.
During recent years, the adsorption process has also come on fore front as one of the major techniques for the removal of heavy metal toxic ions from polluted aqueous wastes. The process has been found to be useful due to its high efficiency, selectivity, low maintenance cost and ease of operation. Hydrous oxides of polyvalent metal ions have efficient capacity to take up cations, including heavy metal ions, and are superior to other adsorbent materials because of their leach resistance property and stability against high temperature and radiations. The ‘radiotracer technique’ has emerged as more sensitive than all other methods and has been used in the study of adsorption over a wide range of adsorptive concentrations (i.e., at micro down to tracer level) even on small surface areas.
This discussion offers a systematic approach to predict the adsorption characteristics of a pharmaceutical pollutant, ibuprofen through artificial neural network. The artificial neural network is inspired by biological nervous system. Artificial neural networks are being extensively used for predicting the rate of adsorption of an adsorbent in solid-liquid adsorption system. Adsorption is a versatile method for the treatment of waste water bearing various pollutants. In case of batch adsorption study, the most significant output of an adsorption process, the adsorption capacity can be predicted either by equilibrium study or kinetic study. But application of a new method for the prediction of ibuprofen adsorption is artificial neural network which bifurcates the conventional prediction methods. In the present investigation, the ibuprofen adsorption capacity of microwave assisted activated carbon was predicted through artificial neural network.
Mitigation of dyes from effluents of industries using dyes is a big problem as it affects not only BOD, COD but also decreases photosynthesis in aquatic plants as it obstucts penetration of sun light into the water.Till now no single technology and adsobent is known to meet desired results. In this study attempts have been made to prepare Steam Activated Pigmented rice Husk Carbon fron easily available, cheap agriculural waste. This book sheds light on optimization of parameters viz initial concentration of dye, adsorbent dose, temperature along with intra particle diffusion, thermodynamic study and kinetic study of adsorption. This book will be a significant tool for researchers and professionals who want to develope cost effective adsorbent to mitigate dyes, toxic compounds and heavy metals from the effluents also to optimize parameters.