Engineering Commons^™

Adsorption Of Iodine And Water On Silver-Exchanged Mordenite, Yue Nan

Dissertations - ALL

The reprocessing of used nuclear fuel to recover the fissile materials generates off gases including radioactive nuclides namely 3H (tritiated water, H3HO), 129I, 85Kr, 135Xe, and 14C. Due to its high quantity in off-gas streams and long half-life (1.59 million years), 129I removal from the off-gas streams is a significant objective of off-gas treatment.

129I retention by solid adsorbents was recognized a better strategy in comparison to liquid scrubbers due to the simplicity of system design and low cost. Among the studied adsorbents, reduced silver-exchanged mordenite (Ag0Z) was widely recognized as the state-of-art adsorbent for iodine removal. It has been …

The Control Of Water Contaminants Assisted By Natural Materials, Wen Zhao

USF Tampa Graduate Theses and Dissertations

Natural materials can be used to remove water contaminants by applying proper physical, chemical, and biological water treatment processes. This study involves using natural materials, as they are considered to be more environmentally benign and cost-effective than synthetic materials. This dissertation concentrates on monitoring five major water quality parameters—ammonia, fluoride, turbidity, pH, and fecal indicator bacteria (FIB) —in two major applications where clean water is needed. The focus is on meeting the water quality requirements for each contaminant. The overall objective of this study is to control the levels of ammonia in aquaculture wastewater, and adjust fluoride, turbidity, pH, and …

Investigation Of The Effect Of Supercritical Carbon Dioxide Extraction On The Adsorption Capacity Of Date Pits, Haliemeh Imad Sweidan

Chemical and Petroleum Engineering Theses

This thesis aims to develop and investigate an innovative use of date pits, a common and abundant agricultural waste in the UAE. It is suggested that date pits may be used to produce date pit oil, and the powder residue from this extraction process may be used as a low cost adsorbent for removal of lead from water. This thesis aims to investigate the effects of the parameters pressure, temperature, and particle size on the extraction yield when using supercritical carbon dioxide (SC-CO₂) to extract oil from date pit powder. This oil is a valuable component which has many applications …

Treatment Of Oil Sands Process-Affected Water Using Activated And Surface Modified Petroleum Coke For Organic Compounds Recovery, Hojatallah Seyedy Niasar

Electronic Thesis and Dissertation Repository

Each day large volumes of oil sands process-affected water (OSPW) are being produced during the extraction of bitumen in oil sands industry in northern Alberta. OSPW contains different polyaromatic hydrocarbons which not only are the major source of toxicity in OSPW, but also create operational problems such as corrosion of the equipment during bitumen recovery process. Therefore, these compounds need to be removed prior to the recycle of the OSPW. In this research, petroleum coke (PC) as an abundant, inexpensive adsorbent was selected as an adsorbent for recovery of chemicals from OSPW. The surface area and adsorption capacity of PC …

Bacterial Cellulose Nanocrystals: Production And Application, Isabela Reiniati

Electronic Thesis and Dissertation Repository

The aims of this study were to investigate the effect of culture conditions on the production of bacterial cellulose (BC) by Komagataeibacter xylinus (K. xylinus), to assess the feasibility of tailoring the surface properties of bacterial cellulose nanocrystals (BCNs) through the culture conditions, and to use the BCNs in an aqueous system for drug adsorption application. BC fibers production improved with increased agitation rates in a stirred tank bioreactor resulting in yields of 0.54 and 1.13 g of BC per litre at agitation rates of 500 rpm and 700 rpm, respectively. Separation and purification of bacterial cellulose were achieved …

Adsorption Of Ammonium (Nh4+) Ions Onto Various Vietnamese Biomass Residue-Derived Biochars (Wood, Rice Husk And Bamboo), Nguyen Van Hien, Eugenia Valsami-Jones, Nguyen Cong Vinh, Tong Thi Phu, Nguyen Thi Thanh Tam, Iseult Lynch

Biochar: Production, Characterization and Applications

This study evaluates adsorption of ammonium nitrogen (NH4+-N) ions onto various biochars produced from biomass residues in Vietnam as a function of their physicochemical characteristics. Three biochars, including wood biochar (WBC), rice husk biochar (RBC), and bamboo biochar (BBC), were produced under limited oxygen conditions using Top-Lid Updraft Drum technology at temperatures of 450-550oC. Physicochemical characterization (BET surface area, Cation exchange capacity (CEC), Scanning Electron Microscopy, Fourier Transform Infrared Spectroscopy) of the biochars was performed in order to link their porosity and surface functional groups with their NH4+-N capture capacities.

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Evaluating The Potential Of Biochar For Reducing Bioavailable Heavy Metal Fractions In Polluted Soil, Rosa I. Soria, Raisa Tjarinto, Stephen A. Rolfe, Steven F. Thornton

Biochar: Production, Characterization and Applications

Previous studies have proposed biochar as a natural adsorbent material with potential to be used in the remediation of polluted soils. Its application for adsorption of pollutants may reduce the bioavailability of harmful compounds in the soil media by limiting its chemical distribution and reducing the risk of uptake by organisms. Therefore, biochar has been suggested for the attenuation of heavy metals (HMs) in soil, minimizing the possibility of accumulation through the trophic chain (Figure ).

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Biochar For Pollutant Removal From Aqueous Solutions, Hamid Trimech, Anastasia Colomba, Franco Berruti, Raffaella Ocone

Biochar: Production, Characterization and Applications

Biochar can be utilised to transfer carbon dioxide from the atmosphere into soils. It can also be used for soil enhancement, due to its attitude to hold water and retain nutrients in soil by adsorbing NH4+ and PO43- ions. Due to its adsorbing capacity, biochar finds applications in removal of pollutants such as ammonia, mercury and organic compounds from waste water.

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Arsenic Removal From Drinking Water By Means Of Low Cost Biochars Derived From Miscanthus And Coconut Shell, Tommaso Marengo, Silvia Fiore, Cedric Briens, Franco Berruti

Biochar: Production, Characterization and Applications

Arsenic is a toxic metalloid highly diffused in groundwater because of natural and anthropogenic factors (mainly deriving from mining activities and pesticides). Inorganic arsenic compounds are classified by the International Agency for Research on Cancer (IARC) in Group I (proven carcinogen). Groundwater concentration of As may vary from 0.5 to 5000 μg/L taking into account more than 70 Countries around the world. The most polluted groundwater of the planet was identified in late 1990s in Bengal delta (Bangladesh and Indian region West Bengal).

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Pyrolytic Temperature Evaluation Of Macauba Biochar For Uranium Adsorption From Aqueous Solutions, Sabine Neusatz Guilhen, Nilce Ortiz, Denise Alves Fungaro, Ondrej Masek

Biochar: Production, Characterization and Applications

Macauba (Acrocomia aculeata) is a palm tree native to the tropical regions of America. In Brazil, it is prevalent in the savannah, known as “cerrado”. A valuable natural and renewable source of vegetable oil for food and cosmetic industries (nut oil) and for biodiesel (mesocarp oil), macauba has the potential to become the new “green gold” of Brazil, not only for its oil quality, but because it could solely be destined for commercial purposes, since it doesn’t compete with food market industry such as soybean and sugar cane. The dark stiff part that protects the nut, called “endocarp”, is generated …

Influence Of Adsorbed And Nonadsorbed Polymer Additives On The Viscosity Of Magnesium Oxide Suspensions, Lisa R. Murray, Jason E Bice, Emily G. Soltys, Christopher Perge, Sebastien Manneville, Kendra Erk

School of Materials Engineering Faculty Publications

Adsorbed polymer additives have been employed to reduce water content and improve cement workability through lowering viscosity, but the influence of over-dosage and the presence of nonadsorbed chains have yet to be fully understood. Model magnesium oxide (MgO) suspensions were used to investigate the potential processing effect of “free” chain concentration on cementitious mixtures. The rheological impact of the free chains was measured through incorporation of nonadsorbing poly(ethylene glycol) (PEG) to suspensions stabilized with an adsorbed comb-polymer superplasticizer. Analyses of the rheological data, that showed viscosity-increases and viscosity-reduction due to free PEG concentrations revealed a transition from depletion flocculation to …

Performance Characterization Of Coagulation Pretreatment For Two Industrial Effluents, Jing Wan

Electronic Thesis and Dissertation Repository

In this work, performances of coagulation and flocculation were tested for two different industrial effluents. Coagulation-Flocculation and activated carbon adsorption were applied for the remediation of oil sands process-affected water (OSPW), generated from oil sands operations in Alberta, Canada. OSPW is a complex mixture of suspended solids, various suspended and dissolved organic compounds. Alum and natural coagulant Opuntia ficus-indica (OFI) were used as the coagulants, and the process was optimized to improve the removal of turbidity and dissolved organic carbon (DOC). The maximum removal of 98% and 63% in turbidity and DOC from OSPW, respectively occurred at pH=6.32, with an …

The Fate Of Fecal Indicator Bacteria In Passive Nitrogen Reduction Systems, Michelle B. Henderson

USF Tampa Graduate Theses and Dissertations

The sustainability of water resources is an international and national concern. With increased human activity, water distribution on a global, regional, and local scale has been negatively impacted. Managing water resources also includes managing wastewater. A promising solution to the issues of water scarcity and distribution in the environment is the reuse of wastewater. Wastewater is produced from various sources (domestic, industrial, and commercial); however, if this water is able to be reused closer to the source of generation it could positively impact water distribution. In the United States, approximately 25% of domestic wastewater is treated in onsite wastewater treatment …

Study On The Dispersion Of Particles At A Fluid-Liquid Interface And Its Application In Hydrophilous Pollination, Naga Aditya Musunuri

Dissertations

This dissertation work describes the physics of particle adsorption and the spontaneous dispersion of powders that occurs when they come in contact with a fluid-liquid interface and its application in hydrophilous pollination of Ruppia Maritima, an aquatic plant. The dispersion of particles can occur so quickly that it appears explosive, especially for small particles on the surface of mobile liquids like water. PIV (Particle Image Velocimetry) measurements show that the adsorption of a spherical particle at the interface causes an axisymmetric streaming flow about the vertical line passing through the particle center. The fluid directly below the particle rises upward, …

Comprehensive Silica Removal With Ferric Compounds For Industrial Wastewater Reuse, Ehren D. Baca

Civil Engineering ETDs

Cooling towers, integrated circuit (IC) manufacture and reverse osmosis (RO) generate copious amounts of wastewater high in colloidal and reactive silica inhibiting on-site or synergistic reuse. Silica present in cooling water can reach solubility limits via evaporation and form impervious scale on heat transfer surfaces that decreases efficiency. When water is treated by RO operating at high rejection, silica forms difficult-to-remove scale on the membrane feed side in the form of glassy patches and communities of aggregate particles, inhibiting aspirations for zero liquid discharge. Current methods for silica scale mitigation include abundant dosing with chemical antiscalents or complex operating schemes. …

Influence Of Activated Carbon Surface Oxygen Functionality On Elemental Mercury Adsorption From Aqueous Solution, Emily K. Faulconer, David W. Mazyck

Publications

Mercury (Hg), though naturally occurring, is a toxic element. Exposure to various forms of mercury can be harmful for humans and ecosystems. Mercury-contaminated wastewater can be treated using activated carbon to adsorb the mercury, allowing for safe discharge. Wet chemical oxidation of activated carbon was performed to enhanced surface oxygen functionality, with the objective of enhancing aqueous ionic (Hg(II)) and elemental (Hg(0)) mercury adsorption. Characterization of the modified carbons included nitrogen adsorption-desorption, elemental analysis, point of zero charge, and total acidity titration. The concentration and identity of the modifying reagent influenced the characteristics of the carbons, including the surface oxygen …

Adsorption Processes For Co2 Capture: An Overview, Paul Webley, Ranjeet Singh, Penny Xiao

CO2 Summit III: Pathways to Carbon Capture, Utilization, and Storage Deployment

Adsorption processes for CO2 capture have gained significant attention in the last decade with hundreds of reports on new adsorbents and processes for capture and removal of carbon dioxide from a range of gas streams. To date, the only commercial examples are removal of trace carbon dioxide in gas streams such as LNG and ASU upstream molecular sieve units. There are no commercial examples of the use of adsorbents to capture carbon dioxide by adsorption processes and deliver a stream of high purity carbon dioxide for sequestration or further processing. In this study, we present the range of processing options …

Adsorption Of Salicylhydroxamic Acid On Selected Rare Earth Oxides And Carbonates, Greer Galt

Graduate Theses & Non-Theses

Adsorption behavior of the anionic collector salicylhydroxamic acid (SHA) on a selected group of rare earth oxides (REOs) and carbonates (RECs) was studied via experimental methods and modelling software. Synthetic oxide and carbonate powders of the rare earth elements cerium (Ce), praseodymium (Pr), europium (Eu), and terbium (Tb) were tested for this research. Studies were conducted at different pH levels to analyze the kinetics of collector adsorption onto the oxide and carbonate surfaces in attempts to optimize recovery parameters for commercial flotation processes using SHA. In addition, thermodynamic software StabCal was implemented to compare theoretical adsorption behavior of collectors SHA …

Sorption Of Benzene, Dichloroethane, Chloroform And Dichloromethane By Polyethylene Glycol, Polycaprolactone And Their Copolymers At 298.15 K Using A Quartz Crystal Microbalance, Abhijeet Radhakrishna Iyer

USF Tampa Graduate Theses and Dissertations

Quartz crystal microbalances (QCM) are acoustic wave sensor systems which are used majorly for vapor and liquid sensing. QCM come under the category of thickness shear mode (TSM) sensors. There are several methods to study organic vapor sensing; the QCM method is the one that offers the highest sensitivity and generates the most data. Solubilities of benzene, dichloroethane, chloroform and dichloromethane in polyethylene glycol (PEG), polycaprolactone (PCL), and several di-block PEG/PCL copolymers at 298.15 K are reported. There are literature data available for most of the solvents in the homopolymers PEG and PCL but no literature data is available for …

In-Situ Observation And Transport Modelling Of Arsenic In Gangetic Plain, India, Pankaj Kumar Gupta, Pranjay Joshi, Jahangeer

Daugherty Water for Food Global Institute: Faculty Publications

The focus of this study is to investigate the arsenic movement and impacts on the residual concentrations on groundwater pollution load. The Gangetic plain area in the Ballia, Uttar Pradesh is selected as study area, which is also reported to extreme arsenic pollution in soil-water system. A modelling approach is developed to assess the arsenic flux in partially saturated zone using data of soil texture, soil hydraulic properties and stratigraphy. Soil type, slope, and land-use cover is considered for estimating the transient flux at the top boundary from daily precipitation and evapotranspiration data of the study area. Solute transport in …

Activated Carbon Preparation And Modification For Adsorption, Yuhe Cao

Electronic Theses and Dissertations

Butanol is considered a promising, infrastructure-compatible biofuel. Butanol has a higher energy content than ethanol and can be used in conventional gas engines without modifications. Unfortunately, the fermentation pathway for butanol production is restricted by its toxicity to the microbial strains used in the process. Butanol is toxic to the microbes, and this can slow fermentation rates and reduce butanol yields. Gas stripping technology can efficiently remove butanol from the fermentation broth as it is produced, thereby decreasing its inhibitory effects. Traditional butanol separation heavily depends on the energy intensive distillation method. One of the main issues in acetone-butanol-ethanol fermentation …

Pure And Binary Adsorption Equilibrium Of Nitrogen And Oxygen In Lilsx Zeolite, Himabindu Gandra

ETD Archive

Chemical products are made by combination of processes that includes synthesis, separation and purification. Separation processes comprises a large portion in these industries and are considered to be critical as most of the applications in chemical industries involves mixtures. Traditional separation methods such as distillation, evaporation, drying etc., requires high energy. For example, air separation to produce nitrogen and oxygen was previously practiced by cryogenic distillation that involves high pressure units and large energy requirement. On other hand, adsorption processes utilize less energy resources and is unique among separation methods. The phase separation is achieved by the existence of a …

Evaluation Of Mass Transfer Rate In Column Of Small Lilsx Particles, Mihikumar S. Patel

ETD Archive

Air separation using zeolite based adsorption processes is a widely-studied topic. Proper process modeling is a key requirement to simulate the process. Conventional process modeling for air separation is designed for large scale adsorption processes using a long cycle time. However, advanced technology now permits to use of a short cycle time using small particles, which significantly reduces the size of the process.
Traditional process models were mostly developed for large particles (dp > 1.5 mm). Typically, it is safely assumed that intra particle diffusion controls the rate of the process while axial dispersion has a much smaller effect. This is …

Dft Study Of Adsorption Of Trimetallic Endohedral Fullerenes On Graphene, Nakul Nitin Karle

Open Access Theses & Dissertations

A density functional theory (DFT) study on the geometric and electronic structure of C60 and Sc3N@C80 along with their adsorption on pristine single layer graphene (SLG) is presented. C60 is found to adsorb in two nearly degenerate configurations: (i) with a pentagon facing the SLG, which is the most stable one, and (ii) with a hexagon facing the SLG in a face-to-face perfect alignment, rarely common in Ï?â??Ï? interactions, 0.06 eV higher in energy. The calculated binding energy of 0.76 eV, which includes dispersion effects, is in good agreement with previous theoretical and experimental reports. On the contrary, Sc3N@C80 adsorption …

Advanced Buffer Materials For Indoor Air Co₂ Control In Commercial Buildings, Pavithra Ethi Rajan

Masters Theses

"The following describes a novel passive approach to control the indoor CO₂ levels in enclosed spaces, primarily focusing on commercial buildings. Amine impregnated silica sorbents were identified as suitable candidates and synthesized; the amine loading ratio was varied to create a range of materials. These samples along with other commercial zeolite candidates have been tested over a range of CO₂ concentrations to determine the CO₂ adsorption capacity in laboratory systems and under simulated room conditions. The research work also focuses on the CO₂ desorption capacity of the candidate adsorbents. The desorption is allowed to occur gradually …

Equilibrium Moisture Content Of Kabuli, Chickpea, Black Sesame, And White Sesame Seeds, Paul R. Armstrong, Elizabeth B. Maghirang, Bhadriraju Subramanyam, Samuel G. Mcneill

Biosystems and Agricultural Engineering Faculty Publications

Sesame and chickpea are important crops in Ethiopia because both are major export crops that generate much revenue for both small farmers and the country as a whole. However, there is a lack of information about the fundamental equilibrium moisture content (EMC) relationships among these crops, which would help facilitate better monitoring and storage. Therefore, EMC adsorption and desorption prediction models based on temperature (T) and relative humidity (RH) were developed for the modified Chung-Pfost and modified Henderson models for Kabuli chickpea (KC), black sesame (BS), and white sesame (WS) seeds. The samples for conducting the adsorption and desorption tests …