Angelo Earvin Sy Choi

De La Salle University | DLSU · Department of Chemical Engineering

In this study, ultrasound-assisted oxidative desulfurization of benzothiophene and dibenzothiophene using ferrate and a phase transfer agent was investigated. The effects of ferrate concentration (100–300 ppm), phase transfer agent (100–300 mg), ultrasonication time (10–30 min), and organic to aqueous phase ratio (10:30–30:10) on sulfur reduction w...

Dibenzothiophene sulfone (DBTO) adsorption utilizing clay material adsorbents such as activated clay, bentonite and kaolinite were investigated in this study. The properties of each adsorbent were characterized using Fourier transform infrared spectroscopy, scanning electron microscope, Brunauer, Emmett and Teller surface area analyzer and zeta pot...

Sludge is a by-product of wastewater treatment, and it has a high-water content. Sludge dewatering is typically performed to reduce its water content prior to its disposal. Dewatering is implemented by combining certain reagents with the sludge followed by a low- or high-pressure process to extract the water from the sludge thereby forming dry soli...

An electrocoagulation treatment is implemented to eliminate the potential waste hazards derived from excessive amounts of total dissolved solids (TDS) and total suspended solids (TSS) prior to its disposal. The overall objective is to concurrently maximize the removal of TDS and TSS of the wastewater and minimize the total energy cost in the electr...

Transition metal chalcogenides (TMCs) have been utilized as cost-effective alternatives for noble metal electrocatalysts, exhibiting comparable activity in the oxygen evolution reaction (OER). Nickel-cobalt selenide (NiCoSe) is a TMC exhibiting significant potential in reducing the overpotential of the oxygen evolution reaction (OER). A carbon-base...

Groundwater contamination is a global concern that has detrimental effect on public health and the environment. Sustainable groundwater treatment technologies such as adsorption require attaining a high removal efficiency at a minimal cost. This study investigated the adsorption of arsenate from groundwater utilizing chitosan-coated bentonite (CCB)...

Adhesives are significant for manufacturing competent, light, and sturdy goods in various industries. Adhesives are an important part of the modern manufacturing landscape because of their versatility, cost-effectiveness, and ability to enhance product performance. Formaldehyde and polymeric diphenylmethane diisocyanate (PMDI) are conventional adhe...

Alternative clean and renewable energy sources have been extensively sought in response to the expanding energy demand and decreasing fuel supplies. Biodiesel has been one of the alternate sources that has been consistently investigated. Accordingly, this study synthesized and characterized a pumice-supported LiOH catalyst further utilized in the t...

The rapid rise of industrialization prompts an increase in wastewater discharge, which worsens water pollution conditions worldwide. Although a naturally occurring metal in water, magnesium can cause environmental problems when discharged with concentrated amounts in exhaust brine and wastewater. Aside from its environmental impact, the recovery of...

Desulfurization technology plays an essential role in the removal of sulfur existing in raw fuel for an immediate aversion of the formation of acid rain and sulfate particulate matters that endanger the environment and public health. In this study, CeO2–WOx–TiO2 catalyst was synthesized by sol–gel method and applied in the oxidative desulfurization...

When sulfur is left in fuel, it has a tendency to be oxidized during combustion and cause problems to engines and harm when released into the atmosphere. One way to reduce sulfur content is by adsorptive desulfurization, which makes use of solid materials as adsorbents to adsorb sulfur from fuel selectively. This process is gaining interest from re...

The release of sulfur-containing compounds into the atmosphere has been a widespread environmental issue throughout the world. In producing fuel oils, oxidative desulfurization (ODS) has been a widely studied alternative method to hydrodesulfurization, as it requires lower operating parameters. Mixing-assisted oxidative desulfurization (MAOD) is a...

The production of green hydrogen can be sustainably achieved through electrolysis using energy from renewable sources. However, the high overpotential of the oxygen evolution reaction (OER) necessitates the development of a cost-effective, active, and stable electrocatalyst. This review explores the synthesis of nickelcobalt chalcogenide catalysts...

The presence of elevated levels of sulfur in diesel oil results in an increased sulfur content in the process stream, which poses significant risks to human health, animals, the environment, vehicles, and infrastructure. Sulfur is a major contributor to particulate matter (PM) and total PM emissions. The level of pollutants emitted is correlated to...

As the population grows, there is a need to address the continuous depletion of non-renewable energy sources and their negative effects on the environment. This led to a substantial assessment of possible innovations and raw materials to increase the volumetric productivity of alternative fuels to supply the energy needed worldwide. In addition to...

Water has always been one of the most significant utilities for humans because of its wide array of applications. The economic impact of the scarcity of supply to clean water for consumption in emergent nations like the Philippines, where a large proportion of the people suffer from water-related diseases due to scarcity of supply to clean water co...

In this research, a process system optimization in the ultrasound assisted oxidative desulfurization (UAOD) with the NaPW/H2O2 system was investigated to determine its sustainability to produce clean diesel. The UAOD process was used to identify the effect of sulfur conversion with ultrasound time (6 to 30 min), amplitude (20 to 60%), catalyst dosa...

Current biodiesel production remains unsustainable and costly due to the use of refined edible oils as feedstock. The use of non-edible oils such as Karanja oil would contribute to making biodiesel production economically competitive based on its availability and low cost. This study determines the optimal esterification conditions of Karanja oil f...

The torrefaction process was applied to the peanut shells to produce charcoal briquette using Cornick industry wastewater as a binder and a charcoal briquetting press. The results showed that the conversion of peanut shell to biochar was 30.1 wt.%. The density and heating values of the three treatments with charcoal to binder ratio of 80:20 (T1), 7...

A water poverty index (WPI) is a multi-criterion indicator that assesses water stress and scarcity that integrates the physical estimates of water availability with the socioeconomic drivers of poverty. However, the decision-making process can be a participatory, iterative process that is characterized by uncertainty due to ambiguity, impreciseness...

There are multiple types of energy technologies that are being developed to focus on the issue of energy security and sustainability. Among these different technologies, the fuel cell microgrid system is a suitable solution for isolated and island communities that suffer from energy poverty, especially in archipelagic countries like the Philippines...

In this research, a case study is presented for the electrocoagulation treatment of wastewater produced in a drilling oil site. The process variables of the electrolysis time and current density were investigated with the response parameters of total dissolved solids (TDS) and energy consumption. A process integration to identify the Pareto front i...

Energy storage can help in solving the problem of intermittency associated with renewable energy as well as provide a reliable and stable energy supply in the transition to a low carbon society. Energy storage technologies (EST) that are available in the market and in the process of development have their specific strengths and weaknesses. The sele...

Desulfurization technology is vital in the removal of sulfur compounds in diesel to attain clean fuels. In this research, the mixing assisted oxidative desulfurization (MAOD) in conjunction with a high shear mixer was used with the catalyst of the activated carbon supported phosphotungstic acid. This study discusses the desulfurization of a simulat...

Fossil-fuel derived oils in its raw form can be treated by oxidative desulfurization (ODS) to effectively remove sulfur compounds. The ODS technology undergoes an oxidation followed by the adsorption process. This research focuses on the integration of a process optimization on the latter part of the ODS. Specifically, the utilization of the activa...

Desulfurization technology is essential to remove sulfur content in diesel oil to achieve clean fuel products. In this study, oxidative desulfurization via ultrasonic bath equipment was utilized in conjunction with a synthesized activated carbon supported phosphotungstic acid (HPW-AC) catalyst. This research focuses on the extent of desulfurization...

Kapok fiber (Ceiba pentandra) belongs to a group of natural fibers that are mainly composed of cellulose, lignin, pectin, and small traces of inorganic compounds. These fibers are lightweight with hollow tubular structure that is easy to process and abundant in nature. Currently, kapok fibers are used in industry as filling material for beddings, u...

This research investigated the feasibility for the cobalt (Co²⁺) and copper (Cu²⁺) recovery from a synthetic wastewater by using the fluidized-bed homogeneous granulation (FBHG) process. Sodium carbonate was used as the precipitant in the operation under a continuous mode in standard atmospheric conditions. The tested parametric variables included...

This research utilized a real raw diesel oil to be subjected in an innovative desulfurization technique. The novelty of this study is in the use of screening analysis in the ultrasonication enhancement of sulfur oxidation in actual fuel. This addresses the research gap in literature that have yet to compare and completely analyze all factors in the...

Green and sustainable strategies aim for the development of manufacturing processes that maximize the use of resources, instigating the semiconductor industry to adopt zero-liquid discharge policies. Complexity and variations in semiconductor wastewater effluents open an opportunity for resource recovery. One such opportunity is the potential recov...

This case study covers the application of the fuzzy optimization in simultaneously satisfying various constraints that include the compliance of ammonia and nitrate concentrations with stringent environmental standards. Essential components in the multi-criteria decision-making analysis is in the utilization of the Box-Behnken design (BBD) response...

Oxalate is a common contaminant found in industrial wastewater particularly in bauxite refining industries. Crystallization in fluidized-bed processes have been established to be effective toward eliminating the problems associated to sludge disposal. In this study, the effects of oxalate removal in a simulated wastewater were investigated at varyi...

The era of industrialization has caused the drastic increase in atmospheric carbon dioxide concentrations that now require various remediation strategies such as CO2 capture and storage. In this study, calcium carbonate granulation is proposed as a new conversion route for CO2 trapped in water matrices into dense solids. Herein, we demonstrate the...

The removal of gaseous hydrochloric acid (HCl) in refineries and petrochemical plants is essential to prevent potential catalyst poisoning, equipment corrosion, and several associated public health and environmental hazards when the acid contaminates the hydrogen–hydrocarbon feedstock. In the present work, the effect of alkanes, alkenes, and liquid...

The granulation of calcium carbonate (CaCO3) exhibited high industrial demand due to its wider application and importance in cement, paper, glass and steel manufacturing. This paper investigated the granulation kinetics of CaCO3 through the fluidized-bed homogeneous granulation (FBHG) process during the homogenous nucleation stage. The CaOH solutio...

This research presents a case study on the remediation of a radioactive waste (uranium: U) utilizing a multi-objective fuzzy optimization in an electrocoagulation process for the iron-stainless steel and aluminum-stainless steel anode/cathode systems. The incorporation of the cumulative uncertainty of result, operational cost and energy consumption...

This research examined the solidification/stabilization process of using a cement binder with actual electroplating sludge. An extensive comparative analysis was done with the cement–sludge mixture before and after the application of cement additives (kaolinite clay, waste latex paint and calcium chloride). The characterization analysis using the F...

A composite silica–divinylbenzene (SiO2/DVB) adsorbent was prepared for the adsorption of ethanol from the ethanol–water mixture. Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, and a Brunauer, Emmett and Teller surface area analyzer were utilized for the characterization analysis of the adsorbents. Batch e...

Wastewater derived from screw producing manufacturing plants contains high zinc concentrations that needs to be treated prior to its discharge. Crystallization through the fluidized-bed reactor has been an effective technology for the removal of heavy metals. In this research, the removal of zinc from a simulated wastewater was investigated by a fl...

In this paper, the synthesis of a chitosan–montmorillonite nanocomposite material grafted with acrylic acid is presented based on its function in a case study analysis. Fuzzy optimization is used for a multi-criteria decision analysis to determine the best desirable swelling capacity (YQ) of the material synthesis at its lowest possible variable co...

In this study, oxidative-adsorptive desulfurization technology was applied to raw diesel containing 1480.4 ppm sulfur. For oxidative desulfurization, the oxidant and catalyst were hydrogen peroxide and phosphotungstic acid, respectively. Two types of continuously mixed reactors: (1) continuous stirred tank reactor (CSTR) and (2) in-line mixer were...

This paper investigates the potential valorization of waste foundry sand (WFS) and fly ash using geo-polymer concrete (GPC) technology, which can reduce the construction materials dependency on the depletion of natural resources. Ground granulated blast furnace slag (GGBFS), fine aggregate, coarse aggregate, fly ash, an alkaline solution and water...

This paper presents the development and evaluation of fuzzy multi-objective optimization for decision-making that includes the process optimization of anaerobic digestion (AD) process. The operating cost criteria which is a fundamental research gap in previous AD analysis was integrated for the case study in this research. In this study, the mixing...

In the assessment of the impacts on the environment of an incineration plant treating industrial waste, a life cycle assessment (LCA) was performed for an incineration plant. The impacts it had, directly or indirectly, were categorized as being toxic and non-toxic. From the three phases of this environmental infrastructure, i.e. industrial waste in...

Abstract Energy depletion and global climate change have stimulated the Korean government to strengthen energy saving and efficiency measures in all sectors. However, in industrial sector where huge energy is consumed, only small portions of the high-grade waste heat from industrial processes have been utilized by another process through industrial...

The adsorption of benzothiophene sulfone (BTO) from model fuel oil was investigated using three different clay mineral adsorbents. The adsorption characteristics of clay mineral adsorbents such as activated clay, bentonite and kaolinite were evaluated using Fourier transform infrared spectroscopy and Brunauer, Emmett and Teller surface area analyze...

Optimization studies of a novel and eco-friendly construction material, Thiomer, was investigated in the solidification/stabilization of automobile shredded residue (ASR) fly ash. A D-optimal mixture design was used to evaluate and optimize maximum compressive strength and heavy metals leaching by varying Thiomer (20-40wt%), ASR fly ash (30-50wt%)...

This study examines the function of Thiomer solidification as a novel environment friendly construction material and its immobilization capacity over heavy metals in the automotive shredder residue (ASR) bottom ash. The morphology of the mixture using a field emission-scanning electron microscopy consistently illustrated the effective bonding betwe...

There is a need for transportation fuel such as diesel oil to undergo a desulfurization process prior to its usage in order to comply with stringent environmental regulations. Predominant organic sulfur compounds present in fuel oils comprise benzothiophene (BT) and dibenzothiophene (DBT). High sulfur compound reduction is attainable through a desu...

Desulfurization of fossil fuel derived oil is needed in order to comply with environmental regulations. Dibenzothiophene and benzothiophene are among the predominant sulfur compound present in raw diesel oil. In this study, mixing-assisted oxidative desulfurization of dibenzothiophene and benzothiophene were carried out using polyoxometalate/H2O2 s...

Mixing-assisted oxidative desulfurization of benzothiophene (BT) and dibenzothiophene (DBT) was investigated using commercial ferrate(VI). The effect of operating parameters such as temperature (50–70°C), agitation speed (7,600–14,000 rpm), and mixing time (10–30 min) were examined in relation to sulfur reduction. Optimization experiments were carr...