Mehrab Mehrvar

Ryerson University · Department of Chemical Engineering

The presence of metals in hot springs has been associated with various adverse health effects. Although some elements are essential for humans, they are dangerous at high levels of exposure. There have been little studies on the presence of metals in hot springs in Colombia, therefore, laboratory tests were carried out over a period of six months (...

High-strength wastewaters from a variety of sources, including the food industry, domestic septage, and landfill leachate, are often hauled to municipal wastewater treatment plants (WWTPs) for co-treatment. Due to their high organic loadings, these wastewaters can cause process upsets in both a WWTP’s liquid and solids treatment trains and consume...

High-strength wastewaters from a variety of sources, including the food industry, domestic septage and landfill leachate, are often hauled to municipal wastewater treatment plants (WWTPs) for co-treatment. Due to their high organic loadings, these wastewaters can cause process upsets in both the WWTP’s liquid and solids treatment trains and consume...

Winery wastewater (WWW) handling strategies often include co-treatment at municipal wastewater treatment plants (WWTPs). Despite this, definitive information regarding oxidation kinetics and process and performance impacts due to co-treatment is lacking. A combined Michaelis–Menten–University of Cape Town kinetic model has been found to best descri...

The Paipa geothermal aquifer system, located in the axial zone of the eastern mountain range of Colombia is the municipality's tourism industry base. Sedimentary rocks characterize the geology of the region with some magmatic intrusions. This study presents a mathematical modelling approach of the system, considering information from secondary sour...

Extended Abstract There are many cities and countries around the world without enough freshwater, and its demand is growing while natural resources are limited. Some estimates show that nowadays four out of every hundred people suffer scarcity of drinking water [1] and the situation will get critical due to the effects of climate change. Drought ha...

Este artículo detalla las regulaciones en la calidad del agua en piscinas y agua potable en Alemania, Canadá y Colombia, con una comparación con la regulación existente y los estándares de calidad de las aguas termales. Canadá, Alemania y Colombia regulan que el agua potable debe estar libre de niveles inseguros de sustancias y patógenos, especific...

Various stages of oil production and processing in petroleum industry produce an enormous amount of oilfield produced water (PW). Discharge of this huge amount of PW has an adverse impact on the surrounding environment as it contains different types of toxic and complex organic and inorganic compounds. For a long time, conventional treatment method...

Classical molecular dynamics (MD) simulations were carried out to analyze the diffusion of saltwater in aquifers at a salinity of 3.5 wt%, and temperatures between 5 and 50°C. Porous systems were built from the quartz stable alpha phase to represent typical compositions and structures reported for aquifer surfaces. The SPC/E model was used to descr...

Despite many wineries being equipped with onsite wastewater treatment, winery wastewater (WWW) co-treatment at municipal wastewater treatment plants (WWTPs) remains a common practice in wine-making regions. The complex and highly variable nature of WWW can result in negative impacts on WWTP operations, highlighting a need for improved co-treatment...

A big challenge of non-enzymatic sensors is their lack of enough selectivity towards the analytes such as glucose, which must be addressed. In this study, a new system of arraying two different electrochemical sensors is designed to achieve glucose-selective and -sensitive non-enzymatic sweat-based sensors. Two kinds of sensors have been fabricated...

Salinity intrusion is a common contamination process that affects coastal aquifers. It has been widely studied and continues to attract research attention. Advances typically apply partial frameworks to analyze factors that contribute to salinity intrusion. Such frameworks frequently overlook their interaction and occasionally oversimplify the aqui...

Polyvinyl alcohol (PVA) is an emerging pollutant commonly found in industrial wastewater, owing to its extensive usage as an additive in the manufacturing industry. PVA’s popularity has made wastewater treatment technologies for PVA degradation a popular research topic in industrial wastewater treatment. Although many PVA degradation technologies a...

Hot springs have traditionally been a tourist attraction in many parts of the world, such as Japan, Canada, Taiwan among others. During the peak tourist season, it is usually discharged into streams without treatment, which can affect the quality of the receiving water, causing negative impacts to the aquatic ecosystems. Downstream ecological impac...

The performance of two continuous UV/H2O2 photoreactors in series under unsteady-state condition is studied. An input–output dynamic model is constructed to describe the degradation of water-soluble polyvinyl alcohol (PVA) in photoreactors. Identification techniques, AutoRegressive with eXogenous input (ARX) and AutoRegressive Moving Average with e...

Due to a relation between glucose in sweat and blood, there is an opportunity to monitor patients' glucose levels non-invasively through sweat. There is a high demand for developing highly selective and sensitive biosensors in order to sense biomarkers like glucose and, therefore, the diseases based on those biomarkers. However, enzymatic sensors a...

Chemical process sustainability has been gaining attention as a comprehensive framework for diagnosing, optimizing, and improving a chemical design. This work presents a comprehensive assessment involving techno-economic, sensitivity, and exergetic factors of two biorefinery configurations for butanol production. The methodology presented here comp...

Considering that functional magnetite (Fe3O4) nanoparticles with exceptional physicochemical properties can be highly applicable in different fields, scaling-up strategies are becoming important for their large-scale production. This study reports simulations of scaled-up production of citric acid-coated magnetite nanoparticles (Fe3O4-cit), aiming...

Considering that functional magnetite (Fe 3 O 4) nanoparticles with exceptional physicochemical properties can be highly applicable in different fields, scaling-up strategies are becoming important for their large-scale production. This study reports simulations of scaled-up production of citric acid-coated magnetite nanoparticles (Fe 3 O 4-cit), a...

The presence of a surface preferably attracting one component of a polymer mixture by the long-range van der Waals surface potential while the mixture undergoes phase separation by spinodal decomposition is called long-range surface-directed spinodal decomposition (SDSD). The morphology achieved under SDSD is an enrichment layer(s) close to the wal...

The Water Footprint (WF) concept allows the quantification of the impact of the production of a wide range of consumer products on local water resources. Each stage in the manufacturing and distribution process adds complexity and variability in the WF estimation. It is, therefore, critical to clearly define the scope of the footprint assessment an...

Doping a transition metal into photocatalysts enhances the photocatalytic activity drastically. In the first part of this study, Taguchi design of experiment is applied to evaluate and optimize the efficiency of the Fe2O3/TiO2 photocatalyst synthetized by thermal method assisted by UV radiation. The contribution percentages of Fe:TiO2 mass ratio, F...

The correct presentation of Table 3 is presented in this paper.

In advanced oxidation processes (AOPs) operating in continuous mode, the flow and therefore, the concentration of oxidants such as H2O2 in the mixing point of the influent must be controlled so that the oxidant residuals in the effluent are minimized while maximizing the organic degradation. Designing a controller to regulate the oxidant flow rate...

The conventional off‐critical polymerization‐induced phase separation (PIPS) of binary mixtures leads to the fabrication of droplet‐type structure. However, the presence of a surface preferably attracting one of the components while phase separation by spinodal decomposition is occurring can change the configuration of surface energy and result in...

Creating novel and innovative nanostructures is a challenge, aiming to discover nanomaterials with promising properties for environmental remediation. In this study, the physicochemical and adsorption properties of a heterogeneous nanostructure are evaluated for the rapid removal of heavy metal ions from aqueous solutions. Core-shell nanostructures...

Background and Aims Optimising the treatment and reuse of winery wastewater (WWW) can have positive environmental significance. Estimating the concentration of various organic compounds, nutrients, and metals via correlations with easily determined parameters could provide a rapid and cost‐effective method of characterising WWW and allow real‐time...

Abstract— The objective of this study is to discuss selected viruses including COVID-19 and their potential elimination processes in hot springs. Studies in Colombia are limited and this scientific discussion provides necessary information regarding these viruses. This includes studies both in Colombia and international levels on the following subj...

A hybrid scaffold of gelatin-glycosaminoglycan matrix and fibrin (FGG) has been synthesized to improve the mechanical properties, degradation time and cell response of fibrin-like scaffolds. The FGG scaffold was fabricated by optimizing some properties of fibrin-only gel and gelatin-glycosaminoglycan (GG) scaffolds. Mechanical analysis of optimized...

The incorporation of sustainability aspects into the design of chemical processes has been increasing since the last century. Hence, there are several proposed methodologies and indicators to assess chemical facilities through process analysis techniques. A comprehensive assessment involving economic, environmental, safety, and exergy parameters of...

An assessment of the rainfall station distribution in the mountainous area of the Regional Autonomous Corporation of Cundinamarca (CAR, for its acronym in Spanish), Colombia, was conducted by applying concepts from information entropy and artificial neural networks (ANNs). This study was divided into two phases: first, a classification of the meteo...

BACKGROUND Photochemical degradations of three commonly used artificial sweeteners, namely aspartame (ASP), acesulfame K (ACE), and sucralose (SUC), are studied in multicomponent aqueous systems, treated through UV/H2O2 process in a recirculating batch reactor. The biodegradation characteristics of the three sweeteners are also investigated in both...

We report a large-scale production of Fe3O4 nanoparticles using the traditional co-precipitation method of iron salts, in which citric acid was used in-situ as capping agent during the synthesis (Fe3O4-cit). WAR algorithm was used to evaluate eight impact categories, human toxicity by ingestion (HTPI), human toxicity by dermal exposure or inhalatio...

This study presents a novel synthesis model for the optimization of water treatment plants considering groundwater desalination and a hybrid arrangement of processing units. The method took into account superstructure optimization and definition of hierarchical levels for the water source, treatment units, and final use according to novel mathemati...

Reactive oxygen species ROS and redox agents are two features of cancer medium, which could be used through responsive drug delivery systems for cancer treatment. Furthermore, mesoporous silica nanoparticles (MSNs) have special characteristics to use them in ROS-responsive and redox-responsive carriers. To shed light on this issue, we propose two d...

The winemaking process produces a large volume of wastewater with highly variable characteristics. Methods in place to manage winery wastewater (WWW) vary, with some wineries treating their WWW on‐site, while others direct the WWW to municipal wastewater treatment plants (WWTPs). Despite the significant presence and growth of the wine industry in N...

In this study, the self-condensation polymerization of a tri-functional monomer in a monomer-solvent mixture and the phase separation of the system were simultaneously modeled and simulated. Nonlinear Cahn–Hilliard and Flory–Huggins free energy theories incorporated with the kinetics of the polymerization reaction were utilized to develop the model...

This study investigates atom transfer radical polymerization (ATRP) of methyl methacrylate (MMA) using activators generated by electron transfer (AGET) as the initiation technique in an emulsion well‐mixed 2L stirred tank reactor. The performance of the AGET ATRP of MMA is analyzed for five key independent variables, namely temperature, catalyst co...

Winery wastewater generated during vinification is often co-treated with the municipal wastewater at the biological sections of the municipal wastewater treatment plants prior to its discharge into the environment, and the grey water footprint associated with these discharges are often neglected from water footprint assessments of the wine-making p...

The aim of this study is to develop a novel photocatalyst doped by a noble metal onto two semiconductor oxides for the applications of photocatalytic wastewater treatment. An alternative preparation method of UV-assisted thermal synthesis is used to synthesize this photocatalyst. The two photocatalysts, Fe 2 O 3 and TiO 2 , were combined with diffe...

Four new stable nickel(II) complexes (1–4) with isothiosemicarbazone- and thiosemicarbazone-based ligands, namely, salicylidine S-propyl-isothiosemicarbazone hydroiodide (H2L¹.HI), 5-bromo-2-hydroxybenzaldehyde S-propyl-isothiosemicarbazone hydroiodide (H2L².HI), salicylidine-thiosemicarbazone (H2L³), and 5-bromo-2-hydroxybenzaldehyde thiosemicarba...

Titanium dioxide (TiO2) is an efficient photocatalyst for removing organics in photocatalytic wastewater treatment, but its low photoactivity limits its practical applications in a visible-light-driven chemical reaction. Many efforts have been made in the activation of the visible light absorption property on TiO2 photocatalyst. In this paper, a th...

Titanium dioxide (TiO2) photocatalysis is one of the most commonly studied advanced oxidation processes (AOPs) for the mineralization of deleterious and recalcitrant compounds present in wastewater as it is stable, inexpensive, and effective. Out of all, doping with metal and non-metals, and the heterojunction with another semiconductor were proven...

This study presents a photochemical kinetics model to describe the degradation of water-soluble PVA (Polyvinyl Alcohol) polymer in a UV/H2O2 batch reactor. Under the effect of UV light, the photolysis of hydrogen peroxide into hydroxyl radicals can generate a series of polymer scission reactions. For a better understanding and analysis of the UV/H2...

Methyl orange, a well-known detrimental azo dye, is treated by N-doped TiO2 photocatalyst synthe¬sized by the simple and effective annealing method. In this study, the effects of light intensity in terms of irradiance by the number of lamps, photon energy and radiation sources, the initial concentration of total organic carbon (TOC), and pH on the...

Current environmental initiatives and global demands for cleaner practices are driving the petroleum refining and petrochemical industries to consider greener methods for the treatment of their industrial wastewater. The photochemical degradation of benzene, toluene, ethylbenzene, and xylenes (BTEX) in petrochemical wastewater by UV/H2O2 and VUV/H2...

In this study, the treatment of mature landfill leachate is evaluated by oxidation with hydrogen peroxide (H2O2) combined with adsorption in a granular activated carbon (GAC) fixed bed column to determinate the increase in the biodegradability index, the reduction of chemical oxygen demand (COD) as well as the increase in the useful life of the GAC...

This study investigates the atom transfer radical emulsion polymerization of methyl methacrylate in a 2 L well-mixed stirred batch reactor using activators generated by electron transfer as the initiation technique. The polymerization was carried out with ethyl-2-bromoisobutyrate as the initiator, copper bromide with 4,4′-di-5-nonyl-2,2′-bipyridine...

The meat processing industry is one of the largest consumers of total freshwater used in the agricultural and livestock industry worldwide. Meat processing plants (MPPs) produce large amounts of slaughterhouse wastewater (SWW) because of the slaughtering process and cleaning of facilities. SWWs need significant treatment for a sustainable and safe...

A nitrogen-doped titanium dioxide composite photocatalyst (N–TiO2) with heterojunction structures is synthesized by three different approaches: a novel UV-assisted thermal synthesis, annealing, and microwave technique. Photocatalytic activities of synthesized photocatalysts are evaluated by the degradation of Methyl Orange under ultraviolet light t...

Advanced Oxidation Processes (AOPs) are promising methods to degrade almost all organics from wastewater. Heterogeneous photocatalysis is an established AOP and a multifactor process. In this study, methyl orange, an azo-dye, is treated by N-TiO2 photocatalyst. Four variables are examined in this study, including light intensity (1, 3, and 5 lamps)...

In this study, a three-factor, three-level Box-Behnken design with response surface methodology were used to maximize the TOC removal and minimize the H2O2 residual in the effluent of the combined UV-C/H2O2-VUV system for the treatment of an actual slaughterhouse wastewater (SWW) collected from one of the meat processing plants in Ontario, Canada....

This study aims to optimize the integration of biological and advanced oxidation processes for the treatment of an actual slaughterhouse wastewater while evaluating the operating costs. A sequence of an anaerobic baffled reactor, an aerobic activated sludge reactor, and a UV/H2O2 photoreactor is examined at the lab scale. Quadratic modeling and res...

A three-factor, three-level Box-Behnken design with response surface methodology and quadratic programming were used to maximize the TOC removal and minimize the H2O2 residual in the effluent of the combined UV-C/H2O2-VUV system for the treatment of an actual slaughterhouse wastewater. The multiple response approach was used to obtain desirability...

Biological and advanced oxidation processes are combined to treat an actual slaughterhouse wastewater (SWW) by a sequence of an anaerobic baffled reactor, an aerobic activated sludge reactor, and a UV/H2O2 photoreactor with recycle in continuous mode at laboratory scale. In the first part of this study, a quadratic modeling along with response surf...

Heterogeneous photocatalysis, an advanced oxidation process (AOP), has shown to be efficient for the degradation of refractory organics in aqueous solutions into simple compounds. Two issues that arise with the use of unmodified TiO2 are the fast recombination of electron/hole pairs and the lower effectiveness in the presence of visible irradiation...

Road traffic noise models are fundamental tools for designing and implementing appropriate prevention plans to minimize and control noise levels in urban areas. The objective of this study is to develop a traffic noise model to simulate the average equivalent sound pressure level at road intersections based on traffic flow and site characteristics,...

The characteristics of the slaughterhouse effluents and current wastewater treatment practices in the province of Ontario, Canada are analyzed. Meat processing plants are found to produce large amounts of wastewater due to the slaughtering process and cleaning of their facilities. Further-more, the composition of the wastewater varies according to...

Degradation and mineralization of aqueous methylene blue (MB) are investigated in a bench scale external loop airlift sonophotoreactor. A central composite design along with response surface methodology is employed to model and optimize the sonophotolytic process. A quadratic empirical expression between responses and independent variables (pH and...

The performance of batch and fed-batch photoreactors with that of continuous photoreactor for the treatment of aqueous polyvinyl alcohol (PVA) solutions is compared. Hydrogen peroxide feeding strategies, residence time, and [H2O2]/[PVA] mass ratio are examined for their impacts on the molecular weight distribution (MWD) of PVA and the total organic...