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Ultrasound-Assisted Post-Pyrolysis Magnetization Of Microporous Biochar For Effective Removal Of Heavy Metals, Ronish Shrestha May 2020

Ultrasound-Assisted Post-Pyrolysis Magnetization Of Microporous Biochar For Effective Removal Of Heavy Metals, Ronish Shrestha

Honors Theses

Low cost and efficient adsorption of heavy metals from wastewater and thorough removal of adsorbent after water treatment have become the two essential needs for the commercial use of any adsorbent. Biochar (BC), the solid byproduct of pyrolysis with microporous carbonaceous structure, has been increasingly recognized as an efficient adsorbent for a vast number of pollutants. Magnetization, though eases the separation and reuse of BC, significantly reduces its adsorption capacity to a comparatively much higher extent. In this study, a hybrid post-pyrolysis magnetization was developed which sustained and even significantly increased the adsorption capacity of biochar. The process included i) …


Urea Functionalization Of Ultrasound-Treated Biochar: A Feasible Strategy For Enhancing Heavy Metal Adsorption Capacity, Baharak Sajjadi, James William Broome, Wei Yin Chen, Daniell L. Mattern, Nosa O. Egiebor, Nathan Hammer, Cameron L. Smith Mar 2019

Urea Functionalization Of Ultrasound-Treated Biochar: A Feasible Strategy For Enhancing Heavy Metal Adsorption Capacity, Baharak Sajjadi, James William Broome, Wei Yin Chen, Daniell L. Mattern, Nosa O. Egiebor, Nathan Hammer, Cameron L. Smith

Faculty and Student Publications

© 2018 Elsevier B.V. The main objective of a series of our researches is to develop a novel acoustic-based method for activation of biochar. This study investigates the capability of biochar in adsorbing Ni(II) as a hazardous contaminant and aims at enhancing its adsorption capacity by the addition of extra nitrogen and most probably phosphorous and oxygen containing sites using an ultrasono-chemical modification mechanism. To reach this objective, biochar physically modified by low-frequency ultrasound waves (USB) was chemically treated by phosphoric acid (H3PO4) and then functionalized by urea (CO(NH2)2). Cavitation induced by ultrasound waves exfoliates and breaks apart the regular …


Studies Related To Chemical Changes In Biochar. I. Polyacrylonitrile Internal Standard To Assess Chemical Changes In Graphene Oxide. Ii. Ultrasonic Effects On Polycyclic Aromatic Hydrocarbons As Models For Biochar, Kaci B. Crawford Jan 2019

Studies Related To Chemical Changes In Biochar. I. Polyacrylonitrile Internal Standard To Assess Chemical Changes In Graphene Oxide. Ii. Ultrasonic Effects On Polycyclic Aromatic Hydrocarbons As Models For Biochar, Kaci B. Crawford

Honors Theses

Biochar has become an increasing area of research due to its reactive edges from stacks of graphene clusters. One particular area of interest in biochar is because it is a potent soil amendment which reduces soil acidity and can reduce greenhouse gas emissions from plants. Also, chemically-modified biochar is being studied as a carbon storage method to potentially mitigate climate change. In order to understand the chemistry that takes place on biochar’s reactive edges during modification, a standard is essential. This research attempted to identify an internal standard that could be added to biochar samples to quantify chemical changes by …


Variables Governing The Initial Stages Of The Synergisms Of Ultrasonic Treatment Of Biochar In Water Saturated With Carbon Dioxide, Adedapo Reuben Adeniyi Jan 2018

Variables Governing The Initial Stages Of The Synergisms Of Ultrasonic Treatment Of Biochar In Water Saturated With Carbon Dioxide, Adedapo Reuben Adeniyi

Electronic Theses and Dissertations

This work investigates the initial stage of the synergistic processes of acoustic treatment of biochar in water saturated with CO2 (AIChE Journal, 2014;60:1054-1065). Treatments with switchgrass and miscanthus biochars have been conducted to examine the effects of acoustic intensity, biochar/H2O ratio, CO2 concentrations of the solution, and that in the headspace above the solution. The changes in biochars’ heating values, carbon and hydrogen contents, internal surface area, and pore size distribution have significant technological implications and are the focal points of this study. The miscanthus and switchgrass biochars were produced via pyrolysis process at 700 oC and 550 oC, respectively. …


The Effects Of Ultrasonic And Photochemical Pretreatment On Heating Value And Carbon Capturing Ability Of Fast Pyrolysis-Derived Biochars, Jordan Houry, Dong Joon Kim, Cary Roy Jan 2017

The Effects Of Ultrasonic And Photochemical Pretreatment On Heating Value And Carbon Capturing Ability Of Fast Pyrolysis-Derived Biochars, Jordan Houry, Dong Joon Kim, Cary Roy

Honors Theses

Slow pyrolysis biochar has been shown to be receptive to ultrasonic and photochemical pretreatment that raises the heating value, surface area, and carbon content of the samples. This experiment was designed to test the feasibility of substituting fast pyrolysis derived biochar in place of slow pyrolysis biochars in order to reduce production times. Furthermore, new biomasses (switchgrass, rice husk, and rice straw) were tested for their receptiveness to pretreatment methods. It was ultimately determined that fast pyrolysis biochars that were exposed to pretreatment increased their carbon content and surface area but did not experience a heating value increase to the …


Carbon Dioxide Capture With Amine Functionlized Graphene Oxide, Renee Zeleszki Jan 2015

Carbon Dioxide Capture With Amine Functionlized Graphene Oxide, Renee Zeleszki

Electronic Theses and Dissertations

Abstract: amine functionalized graphene oxide was used as sorbent in order to achieve carbon dioxide capture. In this study, micro size graphite flakes was prepared according to modified hummers method and "hummers' method with additional kmno4." Graphene oxide was then functionalized with ethylenediamine (eda). Different purification methods for graphene oxide were studied as well as different functionalization method times. Graphite oxide and functionalized graphene oxide has been analyzed with fourier transform infrared spectroscopy (ftir) for chemical structure. Thermal gravimetric analysis (tga) was used to test co2 capture capacity. Functionalized graphene oxide that has been purified with 30 washes via centrifuge …


Carbon Dioxide Capture By Functionalized Graphene Oxide Adsorbent, Sulihat Oreoluwa Aloba Jan 2015

Carbon Dioxide Capture By Functionalized Graphene Oxide Adsorbent, Sulihat Oreoluwa Aloba

Honors Theses

The accumulation of CO2 in the atmosphere is a major environmental hazard. As a result various methods for capturing CO2 was suggested. One of such methods included the development of carbon-based adsorbents due to their large surface area and low heat capacity for CO2 capture which was studied in this report. Graphene oxide (GO) was selected as the adsorbent for its potential benefit in CO2 capture. A modified hummers method was used for the synthesis of GO which showed the existence of the hydroxyl (3440 cm-1), epoxyl (1036 cm-1) and carboxyl (1720 cm-1) functional groups in its FTIR spectra. The …


Thermal And Photochemical Interaction Of Co2 With Biochar, Eneruvie Uyoyou Okinedo Jan 2012

Thermal And Photochemical Interaction Of Co2 With Biochar, Eneruvie Uyoyou Okinedo

Electronic Theses and Dissertations

With interest in the changes that may occur to the carbonaceous portion of biochar obtain through the pyrolysis of biomass, the simple interaction between CO2 and biochar with water or a mixture of water and ethanol as hydrogen donor resulted in three significant observations. These reactions were carried out thermally at 333K and photochemically by simulating energy from the with a xenon lamp. The photochemical reaction involving biochar, CO2 with water or a mixture of water and ethanol as hydrogen donor led to a decrease in oxygen content of the parent biochar material, as observed by an increase in the …


Co2 Adsorption On Solid Sorbents, Bingyu Li Jan 2011

Co2 Adsorption On Solid Sorbents, Bingyu Li

Electronic Theses and Dissertations

Sorbent-based CO2 capture technology is considered as one of the potential scientific techniques for mitigating greenhouse gas emission. Major advantages of sorbent based adsorption are its low regeneration energy coupled with the elimination of corrosion and equipment degradation characteristic of amine based solvent CO2 capture systems which are the preferred industrial methods. Different CO2 capture configurations, processes, and operational parameters for different sorbents were revieand summarized. Efficient industrial applications for CO2 capture require that solid sorbents possess an adsorption capacity between 1000-2000µmol/g or more together with a long-term regeneration capacity. Economical consideration necessitates that the cost of CO2 sequestration be …