Chemical Engineering Commons^™

Advanced Treatment Of Dyeing Wastewater For Reuse By Electrochemical Oxidation, Fei-Xiang Chen, Chu-Yin Yang, Ming-Ming Zhou, Jia-De Wang

Journal of Electrochemistry

In response to the characteristics of dye wastewater, the electrochemical oxidation of effluents from the biochemical process of dyeing wastewater was studied in the electrochemical reactor using PbO₂/Ti electrode as the anode and stainless steel plate as the cathode. The results revealed that the electrochemical oxidation could simultaneously remove the Chemical Oxygen Demand (COD), ammonia and chromaticity. At the residence time of 60 min and current density of 10 mA·cm^-2, the COD, ammonia, chromaticity, concentration of chloride ion and pH values could meet the water standards for “the reuse of urban recycling water-water quality standard for …

Voltage Reversal Behavior In Microbial-Anode Fuel Cells, En-Ren Zhang, Jun-Le Niu, Lei Liu, Guo-Wang Diao

Journal of Electrochemistry

Voltage reversal behavior was investigated in microbial-anode fuel cells (MFCs). Electricity-producing biofilms were developed on the surface of anodes in MFCs inoculated with mixed inoculum from activated sludge. MFC duplicates generally exhibited different performances with respect to the internal resistance, the voltage output and the discharging duration when operating in batch mode. Voltage reversal was observed to occur first in the MFC with lower performance when connecting MFCs in series. Analysis of electrode potentials indicated that the potentials of microbial anodes quickly shifted to more positive values when enhancing discharge current, resulting in voltage reversal in MFCs. Increasing temperature would …

Using Hydrolyzed Sludge Liquor As The Substrate Of Microbial Fuel Cell, Peng Liang, Chao Guo, Xia Huang

Journal of Electrochemistry

Hydrolyzed sludge liquor was used as the substrate of microbial fuel cell. When the thermal treatment time increased from 2 h to 96 h, pH varied little between 7.4 and 8.0. When the treatment time increased, the conductivity, COD and alkaline condition increased to 2.53 mS·cm^-1, 2520 mg·L^-1 and 800 mg·L^-1, respectively. Meanwhile, the power density increased to 25 W·m^-3. The COD removal increased firstly, then decreased, and finally reached the maximum of 47% at the hydrolyzed time of 6 h. The maximal coulombic efficiency was 71% when the treatment time was 4 …

Electrocatalytic Oxidation Degradation Kinetics Of Oxalic Acid In A Cylindrical Electrochemical Reactor With Ti/Iro2-Ta2O5 Anode, Jing Su, Hai-Bo Lin, Hong Xu, Wei-Min Huang, Ya-Peng He

Journal of Electrochemistry

The electrocatalytic oxidation degradation kinetics of oxalic acid in a cylindrical electrochemical reactor with Ti/IrO₂-Ta₂O₅  as an anode was studied. The relation between instantaneous current efficiency and organic concentration in bulk was established based on the two paths for direct electrochemical oxidations, and the theoretical model was verified by experiments. The experimental resultswere reasonably consistent with the established kinetic model. Furthermore, the competition between the two paths was explored with the modelparameter analysis.

Performance Of The Electro-Oxidation And Electro-Fenton Processes With A Bdd Anode For The Treatment Of Low Contents Of Pharmaceuticals In A Real Water Matrix, Sirs Ignasi, Antonio Garrido Jos, Brillas Enric

Journal of Electrochemistry

Here, we report the performance of electro-oxidation and electro-Fenton with a boron-doped diamond (BDD) anode for the treatment of single and multicomponent solutions containing small amounts of pharmaceutical residues (i.e., 1 mg·L^-1 paracetamol and/or 1 mg·L^-1 salicylic acid) spiked into a real water matrix at pH 3.0. Electro-oxidation was performed in a BDD/Pt cell, whereas electro-Fenton was carried out in a BDD/air-diffusion cell to electrogenerate H₂O₂ at the cathode, always operating at constant current density. It was found that the decay of both pharmaceuticals by electro-oxidation was more rapid in the real water matrix than …

Characterization Of Biomass Fuel Properties Based On Functional Groups, Richard B. Reid, Dr. Larry Baxter

Journal of Undergraduate Research

The search for sustainable energy sources and technologies is one of the world’s primary concerns in the 21st century. Biomass energy is projected to be an important component of a diverse and sustainable energy portfolio. In order to utilize this source effectively there must be accurate composition data and predictive correlations for material properties. Though the literature provides some empirical correlations of fuel properties such as heating value [Jenkins et al 1996], fundamental chemical and structural analyses have not been explicitly correlated with such properties. This project has sought to establish relationships between fuel properties and chemical functional group contributions …

A Multi-Physics Model For Solid Oxide Iron-Air Redox Flow Battery: Simulation Of Discharge Behavior At High Current Density, Meng Guo, Xuan Zhao, Ralph E. White, Kevin Huang

Faculty Publications

A rigorous physics-based mathematical model for a solid oxide iron-air redox flow battery system is presented in this paper. The modeled flow battery system combines a Fe-FeO redox couple as the energy storage unit and a regenerative solid oxide fuel cell as the electrical functioning unit in a 2D axial symmetric geometry. This model was developed from fundamental theories of reaction engineering in which basic transport phenomena and chemical/electrochemical kinetics are included. The model shows good agreement with the experimental data. Simulation results for the chemical, electrochemical and transport behavior of the battery are discussed.

Char Combustion And Late Burnout Reactivity, Rhett Brewer, Dr. William Hecker

Journal of Undergraduate Research

To study the effects of the carbon structure on coal reactivity during the late stages of combustion, it was necessary to be able to know what effect mineral content had on the reactivity. Two coals, dietz (high mineral content) and pitt 8 (low mineral content), were chosen for the experiment so that their behavior during the late stages of combustion could be compared.

Hydrothermal Stability Of The Davisil/Cab-O-Sil Silica Catalyst Carriers, Clint G. Guymon, Dr. Calvin H. Bartholomew

Journal of Undergraduate Research

The Fischer-Tropsch Synthesis (FTS) sustained Germany’s fuel needs during World War II as well as South Africa’s since the 1960’s.1 This catalytic technology is enthralling and left to the interested reader to reap in the deluge of information present in the literature. The principle reaction in FTS is a simple polymerization: nCO + 2nH2 ­ [-CH2-]n + nH2O, over a metal such as iron or cobalt. This paper focuses on the problem of hydrothermal stability of silicasupported cobalt FTS catalyst.

Bridging The Gap Between Simulation And Experiment With Multi-State Protein Folding, Jacob Lewis, Dr. Thomas Knotts

Journal of Undergraduate Research

Proteins are made up of extremely long chains of amino acids. Depending on it constituent amino acids, proteins fold in many 3-dimensional patterns to facilitate various biochemical processes such as catalyzing chemical reactions which allow us to live. How proteins fold is thought to be the “holy grail” of biochemistry research and, as of yet, no one has been able to predict exactly how a given sequence of amino acids will fold a priori. Protein folding has been probed in experiment and simulated on computers, but there are discrepancies between the two methods. Naturally, the experimental results are what computer …

Post-Translational Modification In Cell-Free Protein Synthesis, Anna Katz, Dr. Brad Bundy

Journal of Undergraduate Research

The purpose of this project was to examine the phenomenon of eukaryotic myristoylation in a prokaryotic cell-free environment. Basically the idea is that eukaryotic cells such as those within humans have a more robust system for synthesizing protein but it is cheaper, faster, and more easily controlled to synthesize protein in bacteria cells. The problem, then, with using bacteria is that it lacks the ability to perform such functions as post-translational modification; in other words, once the protein has been created through RNA transcription separate enzymes add functional groups to the protein. One such modification is myristoylation, which uses the …

High Temperature Water Gas Shift Catalyst Kinetic Evaluation, Rupak Bajagain, Dr. Morris Argyle

Journal of Undergraduate Research

The purpose of this project was to develop water gas shift catalysts that are more stable and active than the existing ones. Stable catalysts last longer and are more efficient, which is important to economics and to gain widespread application. Currently the demand for hydrogen as a fuel is low but in the future there is a high potential that hydrogen could be important in world energy. This project was performed by a group of undergraduate and graduate students from BYU. Most of the work in the project was performed by group members. The report focuses mainly on the tasks …

Peru Wind Turbine: Electrical, Devin Athey, Dr. Randy Lewis

Journal of Undergraduate Research

This project focused on the design of electrical components for a low-cost, low-speed wind turbine in Peru. The electrical components include the charge controller and the three-phase AC rectifier. These parts, if purchased from retailers, cost $100 and $30 USD respectively. The wind turbine was proposed for low-income residents of villages that are not located near power grids. The focus village was located on Lake Titicaca, Peru. Each family in this village has a monthly income of just under $30 USD. Their current source of electricity comes from solar panels that cost upwards of $1200 USD. In order for a …

Low Volume Dispensing With High Speed Dispensers, Sunny Agarwal

Graduate Dissertations and Theses

With the high pace of innovation in the semiconductor manufacturing industry, there has been an increasing demand for more energy efficient and environmental friendly products. This research relates to a complex process of fluid dispensing at low volumes on a printed circuit board. Currently, a more refined non-contact dispensing terminology named “Streaming” is widely used to stream out material at low volumes for various applications. The key solution is to frame a dispensing method that lends itself most closely to the requirements of a specific production process.

This study represents a detailed approach of dispensing low volumes of materials in …

Indium Diffusion Through High-K Dielectrics In High-K/Inp Stacks, H. Dong, W. Cabrera, R. Galatage, Santosh Kc, B. Brennan, X. Qin, S. Mcdonnell, D. Zhernokletov, C. Hinkle, K. Cho, Y. Chabal, R. Wallace

Faculty Publications

Evidence of indium diffusion through high-k dielectric (Al2O3 and HfO2) films grown on InP (100) by atomic layer deposition is observed by angle resolved X-ray photoelectron spectroscopy and low energy ion scattering spectroscopy. The analysis establishes that In-out diffusion occurs and results in the formation of a POx rich interface.High mobility III-V channel materials are contenders to replace Si in semiconductor devices like metal oxide semiconductor filed effect transistors (MOSFETs) for the sub 22 nm technology node.1 Extensive research is being carried out to determine the validity of these III-V materials for use as the channel, in a variety of …

The Effect Zeolite Addition In Natural Rubber Polypropylene Composite On Mechanical, Structure, And Thermal Characteristics, Nurdin Bukit, Erna Frida

Makara Journal of Technology

This study was conducted to determine the effect of zeolite as filler on mechanical properties, and thermal structure blends of natural rubber and polypropylene (NR/PP). In this study, NR/PP/PP-g-MA blends was filled uncalcined zeolite and calcined zeolite at different weight percent of the 2, 4, and 6%. Samples were characterized to determine the tensile strength, fracture elongation and Young's modulus. Structure of the samples was investigated using XRD method and thermal characteristics were analyzed using DTA/TGA technique. The results obtained for tensile strength showed a significant influence with the addition zeolite of the NR/PP blends at 2% by weight of …

The Plasma Electrolysis Phenomenon In A Two-Compartment Reactor For Chlor-Alkali Production, Nelson Saksono, Fakhrian Abqari, Setijo Bismo

Makara Journal of Technology

Chlor-alkali is one of the most important processes in the chemical industry. It produces chlorine and caustic soda, which become the main feedstock of daily products. The aim of this study is to report the phenomenon of plasma electrolysis and how it can be used in chlor-alkali production for more efficient energy consumption. When the plasma is formed, the current fluctuates and gradually declines. Plasma electrolysis begins with the process of electrolysis itself. Due to Joule heating, gas bubbles are formed and a sheath is made on both electrodes, resulting in the plasma field. Plasma electrolysis can be identified by …

Determining The Air Gap Length Of An Axial Flux Wound Rotor Synchronous Generator, Abdul Multi, Iwa Garniwa, Uno Bintang Sudibyo

Makara Journal of Technology

The air gap length of the designed axial flux wound rotor (AFWR) synchronous generator is determined properly according to the design parameters. One of the distinct advantages of an axial flux (AF) machine is its adjustable air gap. An AF generator’s performance might be controlled by adjusting its air gap. The designed generator has a smallscale capacity that has 1 kW, 380 V, and 50 Hz. The windings are laid into slots made from laminated core. The slots are carved in the face of the stator and rotors. The generator has a single-double-sided slotted wound stator sandwiched between twin rotors. …

Characteristics Of Vacuum Freeze Drying With Utilization Of Internal Cooling And Condenser Waste Heat For Sublimation, Muhammad Idrus Alhamid, Nasruddin Yusuf, Indra Teuku Meurah Mahlia, Engkos Ahmad Kosasih, Muhamad Yulianto, Rio Ricardi

Makara Journal of Technology

Vacuum freeze drying is an excellent drying method, but it is very energy-intensive because a relatively long drying time is required. This research investigates the utilization of condenser waste heat for sublimation as a way of accelerating the drying rate. In addition, it also investigates the effect of internal cooling combined with vacuum cooling in the pressure reduction process. Jelly fish tentacles were used as the specimen, with different configurations for condenser heat waste and internal cooling valve opening. The results show that heating with condenser heat waste can accelerate the drying rate up to 0.0035 kg/m2.s. In addition, pre-freezing …

A New Experimental Approach To Evaluate Plasma-Induced Damage In Microcantilever, Yuki Nishimori, Shinji Ueki, Masakazu Sugiyama, Seiji Samukawa, Gen Hashiguchi

Makara Journal of Technology

Plasma etching, during micro-fabrication processing is indispensable for fabricating MEMS structures. During the plasma processes, two major matters, charged ions and vacuum–ultraviolet (VUV) irradiation damage, take charge of reliability degradation. The charged ions induce unwanted sidewall etching, generally called as “notching”, which causes degradation in brittle strength. Furthermore, the VUV irradiation gives rise to crystal defects on the etching surface. To overcome the problem, neutral beam etching (NBE), which use neutral particles without the VUV irradiation, has been developed. In order to evaluate the effect of the NBE quantitatively, we measured the resonance property of a micro-cantilever before and after …