Department of Chemical Engineering

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    Source Apportionment of PM2.5 in Lahore: Chemical Mass Balance Modeling and Inter-Study variability Assessment
    (Library Information Services, COMSATS University Islamabad, Lahore Campus, 2025) Muhammad Nabeel Khan; CIIT/FA23-RNE-04/LHR; Dr. Wajih Ur Rehman; LHR TP 10010
    Elevated concentrations of fine particulate matter (PM₂.₅) pose a serious public health risk in Lahore due to their ability to penetrate deep into the respiratory system. This thesis applies the U.S. Environmental Protection Agency Chemical Mass Balance receptor model (CMB v8.2) to apportion PM₂.₅ sources using three independent, chemically speciated datasets from Lahore: a winter campaign (February 2019), a year-long monthly study (2019), and paired summer–winter measurements (2022). U.S. EPA source profiles for gasoline and diesel vehicles, biomass burning, coal combustion, road/soil dust, industrial emissions, and secondary Sulfate and Nitrate were employed. Model performance was evaluated using standard diagnostics (R², χ², percent mass explained, t-statistics, and residuals). The winter 2019 analysis showed good model performance (R² = 0.72, χ² = 3.8), with dominant contributions from petrol vehicles (101 µg·m⁻³) and biomass burning (81 µg·m⁻³), along with substantial secondary Nitrate and Sulfate. Monthly CMB runs for 2019 yielded R² values between 0.73 and 0.87, indicating stable performance across seasons. Diesel vehicle emissions peaked during late autumn and winter, while petrol vehicle contributions increased in warmer months. Coal and industrial combustion, together with secondary inorganic aerosols, contributed persistently throughout the year. Seasonal analysis of 2022 data showed PM₂.₅ increasing from approximately 130 µg·m⁻³ in summer to 303 µg·m⁻³ in winter, with acceptable mass closure and statistically significant source contributions. Across all datasets, combustion-related sources—vehicular emissions, biomass burning, and coal combustion—along with seasonally enhanced secondary inorganic aerosols were the dominant contributors to PM₂.₅ in Lahore, while dust sources were more influential during pre-monsoon periods. These results provide higher source resolution than previous PMF/PCA studies and support targeted mitigation strategies focused on vehicle emissions, combustion sources, and precursor gas control
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    Performance Analysis of Heat-Integrated LNG Regasification with Air Separation Units
    (Library Information Services, COMSATS University Islamabad, Lahore Campus, 2025) Muhammad Naeem Khalid; CIIT/FA23-RCH-005/LHR; Dr. Muhammad Haris Hamayun; LHR TP 10009
    Pakistan has a strong dependency on natural gas as an energy source to fulfil both the domestic and industrial requirements. Due to depletion of reserves of natural gas in Pakistan, this gas, in the form of liquefied natural gas (LNG), is imported, mainly from Qatar. However, there are several issues associated with this imported LNG. The LNG needs to be regasified before use in the existing infrastructure, the calorific value of imported LNG is higher than the design specifications, and the cold energy/exergy stored in LNG is wasted via the current method of regasification, mixing with the remaining reserves of natural gas. To overcome these issues, there is a need to integrate LNG regasification process with a process that can provide an inert, i.e., nitrogen to lower the calorific value of this LNG to meet the existing design specifications, to extract/use the cryogenic energy of LNG to lower the overall energy requirements, and eventually to regasified LNG for onward use by the users. Cryogenic air separation process appears to be the most suitable process for the integration with LNG regasification that can help in achieving the required objectives. Accordingly, this study aims to integrate the cryogenic air separation process and LNG regasification process, and the model is developed using Aspen HYSYS® V15. To the best of our knowledge, the developed process is examined using exergy, advanced exergy and exergoeconomic analyses, however, so far, optimization via evolutionary algorithm is not reported in literature. Therefore, this research gap is addressed in this study by employing teaching learning self-study-optimization algorithm. The base case model developed in Aspen HYSYS® V15 is integrated with MATLAB and the algorithm is applied to carry out rigorous optimization. The optimization results show an increase in the air processing capacity from 500 tons per hour (TPH) to 638.9 TPH with the maximum utilization of the cryogenic energy of LNG. The overall specific energy consumption is increased by 21.66% keeping the same energy consumption of air. Followed by the optimization, the process is then evaluated thermodynamically using the exergy analysis. The analysis demonstrated that the % exergy efficiency of the optimized process is 72.51% with an exergy destruction of 36.42 MW. The overall optimized process may help in providing a more feasible and sustainable design toward the practical implementation of this integrated configuration in context of Pakistan.
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    Bimetallic Nanoparticles on Eggshell-Derived CaO Catalyst for Efficient Biodiesel Production
    (Library Information Services, COMSATS University Islamabad, Lahore Campus, 2025) Ali Murad; CIIT/FA23-RCH-001/LHR; LHR TP 10008; Dr. Murid Hussain
    The transformation of agricultural waste into an effective catalyst will not only provide clean energy but also help to minimize waste disposal issues. In this study, leftover eggshell powder was calcined at 900 oC to make CaO powder, which is then incorporated with Ag and Cu nanoparticles synthesized through a green route by utilizing polyalthia lonfifolia plant extract. Four catalysts categorized as CaO, Ag/Cao, Cu/CaO, and Ag-Cu/CaO were prepared and utilized in the transesterification reaction separately. Rice bran oil was utilized to make FAMEs by employing these four catalysts separately. The prepared catalysts were characterized by XRD, FTIR, TGA, and SEM, while BET (for Ag-Cu/CaO only) was used to assess the catalysts’ crystalline shape, structural changes upon doping. The bimetallic doped heterogeneous nano-catalyst (Ag-Cu/CaO) provided a maximum biodiesel yield 99% at optimum reaction conditions (oil to methanol 1:9, reaction time 3hr, temperature 65 oC, catalyst loading 3 wt%). The single doped catalyst, such as Ag/CaO, provided 92% apparent biodiesel yield, Cu/CaO provided 93% yield at optimum conditions. The undoped CaO nano-catalyst offered a lower biodiesel yield of only 88% at optimum conditions. The biodiesel prepared by utilizing Ag-Cu/CaO nano-catalyst at optimum conditions was assessed by GC-MS for the confirmation of FAMEs preparation. In addition to this, biodiesel characteristics such as Cloud point, pour point, Flash point, and density were also investigated and compared with ASTM D6751 standards. The apparent biodiesel yield and parametric studies were utilized to evaluate the catalytic effectiveness of CaO, Ag/CaO, Cu/CaO catalysts in the transesterification reaction for biodiesel production.
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    Production of Hydrogen Rich Gas Through the Process of Steam Reforming: An Experimental and Simulation Study
    (Library Information Services, COMSATS University Islamabad, Lahore Campus., 2025-04-01) Muhammad Zain Feroz; CIIT/FA23-RNE-008/LHR; Dr. Um-e-Salma Amjad; LHR TP 9677
    The objective of this research is to produce Hydrogen, a clean source of energy, through the steam reforming process, from hydrocarbons as feedstock. It emphasizes the development of catalysts that are capable of addressing the challenges of stability and efficiency. This study focuses on the use of tools like DWSIM to determine the operating conditions for enriched hydrogen yield. The research involves catalyst synthesis through the combustion synthesis method to synthesize different catalysts. This method involves using a vaporizer and reactor setup at controlled temperature and pressure. Whereas, after the SR process, the gas composition of the product will be analyzed through the use of a gas analyzer. It will shed light on the efficiency of the process and trace impurities in the product gas. The research focuses on reducing the oxides of carbon in the final product for maximum hydrogen production and to comply with global carbon emission standards.
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    Conducting Polymer Coated Carbon Fiber Composites for Enhanced Strain Sensing Applications
    (Library Information Services, COMSATS University Islamabad, Lahore Campus., 2025-04-01) Fazila Khalil; CIIT/FA23-RNE-011/LHR; Dr. Imran Hassan; LHR TP 9809
    In modern applications, such as robotics, wearable, and healthcare, strain sensors are crucial as it is possible to accurately measure mechanical defects. The objective of this research was to improve strain sensing of carbon fiber (CF)-based materials by using surface modifications and conducting polymer (CP) coating. Sulfuric acid and nitric acid were used by the ratio of 3 to 1, to etched carbon fiber (e-CF) by making the surface rougher and having more functional groups to improve adhesion to the polymer. Composites consisted of CF coated with polyaniline (PANI) were synthesized through in-situ polymerization and then coated with Poly(3,4-Ethylenedioxythiophene): Polystyrene Sulfonate (PEDOT:PSS) to give composites based on conducting polymers. The structural, chemical and thermal characterization of the synthesized composites was done using X ray diffraction, Fourier-transform infrared spectroscopy, and thermogravimetric analysis. Electrical conductivity and strain-sensing capability were assessed during several forms of bending, including finger, wrist, and elbow motions. The sample with PEDOT:PSS coated on top of PANI coated e-CF showed the highest sensitivity, as well as superior thermal stability and electrical conductivity, compared to the other composites. This study demonstrates that changing the surface and coating with two different types of CP can significantly enhance the overall characteristics and performance of CF-based composites. These findings indicate a potential interest in employing CP coated CF composites as high performance strain sensors in healthcare, wearable electronics, robotics, and smart textiles as well.
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    Development of Functional Materials for Energy Harvesting Devices
    (Library Information Services, COMSATS University Islamabad, Lahore Campus., 2025-04-01) Mubashra Mushatq; CIIT/FA23-RNE-010/LHR; Dr. Maria Mustafa; LHR TP 9679
    The need for new materials with enhanced functionality, structural stability, and energy conversion efficiency has increased due to the growing need for renewable energy solutions. Functional energy materials because of their large surface area, adjustable porosity, find their versatility in various applications, such as sensors, energy storage, and energy harvesting devices. The thesis work will explore and optimize the importance of the development of advanced functional material on energy harvesting devices, i.e., triboelectric nanogenerator (TENGs) to address the increasing demands of efficient and sustainable renewable energy sources. The research lies in the synthesis of Zeolitic Imidazolate Framework-67 (ZIF-67), Polyvinylidene Fluoride (PVDF), and Sodium Niobate (NaNbO3) materials owing to their large surface area, controllable porosity, and sturdiness to facilitate energy conversion performance. Such materials were reduced to form thin films by careful manufacturing methods, e.g. electrohydrodynamic (EHD) spray deposition, drop casting, etc. and inserted within TENG devices with aluminum and copper electrodes to maximize charge transfer and surface functionality. To explore the materials structural, optical, and electrical properties, UV-Vis spectroscopy, FTIR, SEM, and I-V measurements were performed in order to achieve thorough characterization of the materials as they would be used in energy applications. Tests determined that performance of TENGs with these functional materials were much greater than those of a baseline as the NaNbO3 -PVDF system showed an outstanding power generation owing to its piezoelectric and ferroelectric characteristics. Nevertheless, compatibility issues of the material were found at ZIF-67/NaNbO3 composite, which supports the idea of making a strategic selection of material. These results suggest the opportunities of custom functional materials to instruct energy harvesting technologies, which can provide scalable and sustainable energy supply of flexible electronics, sensing and energy storage.
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    Fabrication and Performance Evaluation of Polyaniline-Based Composites within a Sandwich Structure Device for Flexible Electronics Application
    (Library Information Services, COMSATS University Islamabad, Lahore Campus., 2025-04-01) Sohail Ahmad; CIIT/FA23-RNE-009/LHR; Dr. Abrar Faisal; LHR TP 9678
    This study describes the manufacturing and characterization of polyaniline (PANI) based composites targeted at flexible electronics and their application in a sandwich style device architecture. The fundamental methodology was the production of conducting PANI and PANI-Bismuth Ferrite composite by a chemical oxidative in-situ polymerization technique. These synthesized powders were further processed into stable and processable conductive inks, N-Dimethylformamide (DMF) as the solvent, and polyethylene glycol (PEG) and sodium silicate being used as binders and stabilizers. In order to measure electrical performance, a flexible copper and aluminum substrate was electrolessly deposited with these inks to form a sandwich-structure device to be used as an active layer placed between conductive contacts. The FTIR results established the achievement of the production of PANI along with its composite with BiFeO3. A characteristic movement of functional groups meant that BiFeO3 and PANI interacted heavily on the composite structure. All three pure components as well as the final composite were characterized fully using current-voltage (I-V) characterization. The I-V analysis confirmed a non-linear, semiconducting type of PANI and amplified a discrete rectifying, diode like characteristic of the BiFeO3. More importantly, the PANI-BiFeO3 composite had a characteristic non-linear, asymmetric I-V curve, which is an indication of successful functional combination. This was supported more by optical analysis using UV-Vis spectroscopy and Tauc plots to get band gaps of PANI, BiFeO3, and a different one was a modified 2.83 eV in the composite.The combination of all results justifies the PANI-BiFeO3 composite as an ideal candidate in the development of workable and bendable electronic components and has laid a scale-dependent production path in addition to providing initial insights regarding the electro-optical behavior which will be useful in the design of flexible sensors, energy storage, and portable devices.
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    Developing A Novel Method for H2O2 Production via Integration of Photocatalysis and Underwater Friction
    (Library Information Services, COMSATS University Islamabad, Lahore Campus., 2025-04-01) Muhammad Yasir; CIIT/FA23-RNE-007/LHR; Dr. Fahad Rehman; LHR TP 9676
    Hydrogen peroxide (H2O2) is a commodity chemical, an environmentally friendly oxidant and difficult to synthesize commodity chemical, but its production in industry is restricted to a hazardous, energy-intensive, anthraquinone auto-oxidation (AO) process, which is economically feasible only when used inexpensively at large scales and is highly waste producing in terms of organic products. This semicentral model of production requires a transport of highly concentrated, and therefore dangerous, H2O2 solutions. This thesis proposes a new direction and a decentralized method towards the sustainable production of hydrogen peroxide through synergistic combination of photocatalysis and underwater mechanical energy, i.e. friction and sonication to tackle these economic, environmental and safety issues. The proposed methodology does not need the hazardous chemical inputs, and it is conducted in ambient conditions. The essence of the research work was in uniform study of a composite system in suspension (glass powder, or quartz, and polytetrafluoroethylene, or PTFE, particles in water), which undergoes both UV treatment and intense probe sonication. The synergetic mechanism assumed in the study is as follows: photocatalysis of the semiconductor material itself would transform to the electron-hole pair generation process, and mechanical energy addition would play several important roles (1) stimulating the process of charge separation and migration, including the triboelectric effect, and the piezoelectric effect on the surface of the material; (2) producing more radical precursors (or •OH) owing to sonolysis and acoustic cavitation; and (3) creating active surfaces and reducing mass transfer limitations occurring continually. To maximize the process a complete parametric study was made that would analyze the effects of various material concentrations, reaction time, temperature and the effect of sonication itself in a systematic manner. Conclusively, the results indicate that H2O2 was successfully produced, and a yield of sufficient increase was realized when sonication was added, which is the apparent validation of the proposed synergistic effect of improvement. The best conditions were found, and the process had shown a high degree of reproducibility, which proves the advantageousness of the practice. Successfully developed a novel, dual-energy ix system for sustainable H₂O₂ production, achieving a maximum yield of 5.48 mgh⁻¹cm⁻² under optimized conditions (120 min, 25g glass + PTFE, 22-26°C). The present work presents the main concept of a novel dual-energy target design that uses the forces of both light and mechanical energy as a source of chemical synthesis. The results mark a milestone in the establishment of green, on-site, and on-demand technologies of producing H2O2 and the potential applications that utilize this concept are monumental like water treatment and disinfection.
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    Synthesis and Characterization of MIL-101/PAN Membranes for Water Treatment
    (Library Information Services, COMSATS University Islamabad, Lahore Campus., 2025-04-01) Shafqat Ullah; CIIT/FA23-RNE-006/LHR; Dr. Mehwish Batool; LHR TP 9675
    The problem of water pollution and shortage is one of the most topical global issues in the 21st century, and the creation of its purification technology that becomes efficient and environmental saving is a prompt necessity. This study introduces the synthesis and characterization of metal-organic framework, mixed matrix membranes (MMMs) of MIL-101 and polyacrylonitrile (PAN) in a view of advanced water treatment. Composite membranes were prepared by incorporation of the MIL-101 and the PAN polymer matrix by phase inversion and electrospinning process. MIL-101 was found to be highly porous, with a high surface area, and chemical stable, and by incorporating the Nano and the PAN membranes could be tailored in order to absorb the energy of a wider range of energy. The FTIR, SEM, TGA, and contact angle techniques were adopted to study the membranes synthesized by characterizing their structural integrity, surface morphology, thermal stability, and hydrophilicity. MIL-101/PAN membranes performance was measured by water flux, rejection efficiency, and reusability to remove the heavy metals, dyes and salts. The findings demonstrated that the membrane permeability and pollutant rejection was hugely better after the addition of MIL-101 leading to an increase in porosity and active sites. The membranes also exhibited excellent possessive nature and strength after more than one passage of filtration process. This study validates the prospective of the MIL-101/PAN composite membranes system as a potentially effective, scalable and cost-efficient method of purifying water especially in the purification of industrial effluents and fresh brackish water.
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    Synthesis and Performance Investigation of Biowaste derived Biochar Pellets for Desulfurization of Biogas
    (Library Information Services, COMSATS University Islamabad, Lahore Campus., 2025-04-01) Rabia Mahmood; CIIT/FA23-RNE-005/LHR; Dr. Muhammad Aslam; LHR TP 9674
    Bio-waste, energy resources and climate change concerns coupled with the sustainability of the nexus of bio-waste, and energy have changed the perception from a waste to resource of energy. Renewable technologies, such as solar, wind, hydro, and biogas energy have proved alternative for fossil fuel energy. The problem attached with raw biogas is the presence of hydrogen sulfide (H2S), which does not only reduce energy potential, but also contributes in environmental pollution. H2S is highly corrosive and shows hazardous effects on human health. Therefore, it is essential to desulfurize the biogas. There are different physical, chemical and biological techniques to remove H2S gas from biogas such as adsorption, absorption, dry scrubbing, wet scrubbing, membrane filtration and bio tricking filters etc. Unlike complex physical, chemical or biological processes that may require high pressure, temperature, or specific operational conditions, biomass and biochar adsorption process is generally simple to implement and operate. The superior properties of biochar such as high surface area, porous structure and functional group make biochar an effective adsorbent in removal of H2S in biogas. BC pellets were fabricated for performance evaluation of sulfur removal from biogas. The pellets of biochar exhibited removal efficiency of H2S better than biomass pellets. The best adsorption of H2S was shown by the combination of biochar pellets of date seeds and banana peels. The results suggested that biochar pellets offer a promising, ecofriendly alternative to conventional desulfurization methods in small to medium scale biogas systems. The use of bio-waste-derived biochar for the removal of H2S in biogas from anaerobic digester can potentially turn waste material into a sustainable alternative to conventional adsorbents by using waste valorization concept to upgrade the bio methane. This study can potentially address the Sustainable Development Goals (SDGs) of United Nations.