Engineering Commons^™

Impact Of Granular Activated Carbon On In-Situ Reductive Dechlorination Of Chlorinated Solvents, Reagan Gregory

All Theses

Treatment of chlorinated solvent-contaminated aquifers with in-situ activated carbon offers a simple yet cost-effective treatment opportunity, yet the interactions between activated carbon and the chlorinated solvents and their daughter products are not well understood.

The objective of this research is to demonstrate the impacts of in situ activated carbon on complete reductive dechlorination of chlorinated solvents in contaminated aquifer material with mixed dehalogenating cultures. This research seeks to characterize the sorption of trichloroethene and its daughter products cis-dichloroethene, vinyl chloride, and ethene to granular activated carbon and how that sorption relates to the removal of trichloroethene from contaminated material in …

Carbon Injection To Support In-Situ Smouldering Remediation, Gillian Wilton

Electronic Thesis and Dissertation Repository

Per- and polyfluoroalkyl substances (PFAS) are a group of anthropogenic contaminants that are growing increasing concern due to their associated negative health affects. The properties of PFAS result in their persistence and stability which present challenges for remediation. Activated carbon is currently the most widely used method for PFAS treatment since carbon microparticle injection can be used for in-situ treatment; however, this method does not result in PFAS destruction. Thermal treatment is a promising post-treatment method that can be used with activated carbon as long as sufficient PFAS-destroying temperatures are achieved (> 900°C). A promising in-situ thermal treatment technology is …

Production Of Engineered Carbons From Secondary Waste Streams For Environmental Applications, Ghazaleh Chegini

Electronic Thesis and Dissertation Repository

Pyrolysis and activation were used in this thesis to produce biochar and activated carbon from industrial digestate and hydrochar materials. In the first part of thesis, digestate derived biochars were obtained by varying the pyrolysis heating rate (10, 80, 100, 200, >1000 °C·min^-1) and temperature (300 to 600 °C) to modify their soil-related characteristics (i.e., nutrient leachability, carbon stability, and heavy metal adsorptive capacity). The biochar produced at a temperature of 500 °C and heating rate of 10 °C·min^-1 was also activated under using CO₂ at 800 °C with different holding times (0.5-2 h). Results indicated …

Smouldering Combustion Treatment Of Soils And Granular Activated Carbon Contaminated With Per- And Polyfluoroalkyl Substances, Alexandra L. Duchesne

Electronic Thesis and Dissertation Repository

Per- and polyfluoroalkyl substances (PFAS) are emerging contaminants, ubiquitous in the environment, and are challenging to remediate. Self-sustaining Treatment for Active Remediation (STAR) destroys organic contaminants embedded in porous media using smouldering combustion. Self-sustaining smouldering conditions allow the reaction to propagate through the contaminated media without external energy. This study explored STAR as a remediation option for PFAS-impacted granular activated carbon (GAC) and PFAS-contaminated soil. Three smouldering mixtures were used (i) PFAS-spiked GAC and sand, (ii) PFAS-spiked soil and GAC, (iii) PFAS-contaminated field site soil and GAC. Smouldering temperatures were greater than 900˚C, destroying the GAC. Post-treatment PFAS concentrations of …

Evaluación Del Biochar Obtenido Por Pirólisis Del Retamo Espinoso Para Remover Cromo Del Agua, Katalina Yulieth Gómez Zuñiga, Nubia Rocío Quevedo Gamba

Ingeniería Ambiental y Sanitaria

Se discute en este trabajo la utilización del biochar obtenida a partir de la pirólisis de residuo orgánico de Ulex Europaeus, especie invasora de la región andina de Colombia con el objetivo de emplear el biochar en la remoción de cromo en una muestra de agua tomada de la Cuenca Alta del Rio Bogotá. Metodológicamente el proyecto fue desarrollado en dos fases. En la primera fase se obtuvo el biochar a partir de residuo proveniente de Ulex Europaeus; se llevó a cabo el proceso de pirólisis a temperaturas de 450 °, 550 °, 650 ° C y se determinaron las …

Design Of Efficient Carbon-Based Adsorbents For The Removal Of Organic And Inorganic Water Contaminants, Sayedeh Soroosh Mortazavian Dehkordi

UNLV Theses, Dissertations, Professional Papers, and Capstones

Granular activated carbon (AC) and biochar (BC) are two carbon-based adsorbents commonly used for water and wastewater treatment. However, these adsorbents have drawbacks that suppress their aqueous contaminants removal efficiency. Their major disadvantages are that AC has low selectivity and reusability potential, and BC has a hydrophobic nature.

The scope of this dissertation is to enhance the performance of commonly-used carbon-based adsorbents for the removal of organic and inorganic water contaminants and to understand the interactive mechanism of contaminants’ ions/molecules with adsorbents. Hexavalent chromium (Cr(VI)) and trichloroethylene (TCE) are two types of inorganic and organic water contaminants, respectively, which are …

Value Added Products From Lignin And Biomass Derivatives, Chen Li

Civil & Environmental Engineering Theses & Dissertations

Pyrolysis is one of the traditional lignin and biomass utilization methods. The liquid products bio-oil and solid products bio-char are the main value-added products from lignin pyrolysis. Due to the narrow application and low quality, using the pyrolysis method to produce bio-oil and bio-char cannot bring sufficient economic benefits. In this dissertation, two methods were investigated to improve the quality of lignin bio-products.

Instead of direct pyrolysis, chemical activation (pyrolysis) was introduced in this dissertation. Compared to bio-char, the lignin chemical activation product lignin-activated-carbon has better economic value. With the best activation conditions, the lignin-activated-carbon produced a surface area of …

Regeneration Potential Of Activated Petroleum Coke For Application In Oil Sands Process-Affected Water, Sreejon Das

Electronic Thesis and Dissertation Repository

Cost effective regeneration of spent adsorbent is crucial for large scale application of adsorption as a viable separation process. While adsorption studies are abundant in literature, systematic and comprehensive regeneration studies are seldom reported in open literature. A proprietary activated carbon from petroleum coke was used for the removal of model naphthenic acids (NAs) and organic compounds from oil sands process-affected water (OSPW). A systematic and comprehensive study was conducted to regenerate the adsorbents. Methanol with aqueous NaOH (pH adjusted to around 12) was applied to regenerate the spent commercially available granular activated carbon (GAC) and activated petroleum-coke (APC). Optimization …

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 …

Procedural Treatment Options To Address Intermittent Pentachlorophenol Effluent Exceedances At A Former Wood-Treatment Site In Butte, Montana, Travis Dunkle

Graduate Theses & Non-Theses

The Montana Pole and Treating Plant in Butte, Montana treated wood with preservatives, mainly pentachlorophenol (PCP), which had been dissolved in a carrier fluid. Accidents and careless handling spilled large quantities of the fluid on the site, contaminating the vadose zone and groundwater. This site has been undergoing remediation since it was added to the CERCLA National Priorities List in 1987. Pentachlorophenol and dioxin are the contaminants of concern. Remediation technologies have included soil removal and installation of two water recovery trenches that collect groundwater, which is then pumped through a granular activated carbon (GAC) water treatment system. There were …

Removal Of Perfluorooctanoic Acid From Water Using Primitive, Conventional And Novel Carbonaceous Sorbent Materials, Christopher K. Brown

Theses and Dissertations

Polyfluoroalkyl Substances (PFAS), like perfluorooctanoic acid, have been used for the last 50 years in a wide variety of industrial processes and consumer-based products, including polymer additives, lubricants, fire retardants and suppressants, pesticides, and surfactants (Buck et al. 2015). The Department of Defense (DoD) has used PFAS-based Aqueous Film Forming Foam (AFFF) at fire training facilities and aircraft hangars. AFFF has contaminated approximately 600 sites classified as fire training facilities with PFAS (Huang, 2013).

This study focused on testing the most likely carbonaceous adsorbent compounds to remediate PFAS-contaminated sites on Air Force installations. Batch tests were performed to determine the …

Cyclic Heating To Inhibit Bacterial Growth In Activated Carbon Point-Of-Use Treatment Devices, Irwin Silverstein, Irvine W. Wei

Irvine W. Wei

The effectiveness of using heat treatment on a cyclic basis as a means of inhibiting bacterial growth in activated carbon point-of-use treatment devices was examined. Heat treated and non-heat treated devices were compared in a controlled experiment with respect to parameters such as standard plate count, total organic carbon, total residual chlorine and head loss. The results of the study indicated that cyclic heat treatment can inhibit bacterial growth on the surface of granular activated carbon without compromising total organic carbon and total residual chlorine removal efficiencies or accelerating head loss. Microbiological testing verified that the control device had become …

Applications Of Activated Carbons Obtained From Lignocellulosic Materials For The Wastewater Treatment, Ma. Del Rosario Moreno-Virgen, Rigoberto Tovar-Gomez, Didilia I. Mendoza-Castillo, Adrian Bonilla-Petriciolet

Adrian Bonilla-Petriciolet

This chapter provides an overview of the application of activated carbons obtained from lignocellulosic precursors for wastewater treatment. Analysis and discussion are focused on the performance of different activated carbons obtained from several precursors and their advantages and capabilities for the removal of relevant toxic compounds and pollutants from water.

Lignocellulosic Precursors Used In The Synthesis Of Activated Carbon: Characterization Techniques And Applications In The Wastewater Treatment, Virginia Hernández-Montoya, Adrian Bonilla-Petriciolet

Adrian Bonilla-Petriciolet

The activated carbon is the universal adsorbent used in the removal of water pollutants such as dyes, heavy metals, fluoride and arsenic, among others. The commercial activated carbons are generally obtained from wood and coconut shell. However, in recent years, other lignocellulosic materials have been used as precursors in the synthesis of this adsorbent for specific applications. This book discusses and analyzes key aspects concerning to the preparation, characterization and application of activated carbons obtained from different lignocellulosic materials. Based on the fact that the activated carbon is used in a broad variety of treatment systems, this book will be …

The Effects Of Physical Factors On The Adsorption Of Synthetic Organic Compounds By Activated Carbons And Activated Carbon Fibers, Hatice Kose

All Theses

Activated carbons (ACs) and activated carbon fibers (ACFs) have been extensively used for the removal of synthetic organic compounds (SOCs) that have been found to be toxic, carcinogenic, mutagenic or teratogenic. Adsorption of these compounds on ACs and ACFs are controlled by both physical factors and chemical interactions, which depend on the characteristics of the adsorbent (surface area, pore size distribution (PSD), and surface chemistry), the nature of the adsorbate (molecular weight and size, functional groups, polarity, solubility), and the condition of the background solution (pH, temperature, presence of competitive solutes, ionic strength). Since there are several mechanisms that can …