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The TiO2/diatomite composites with excellent adsorption and photo-degradation performances were leveraged to investigate the influences of calcination temperature and operating factors on their properties. The results showed that the calcination temperature was closely bound up with the crystallization of TiO2 and the specific surface area of composite. The composite with calcination temperature of 550 °C exhibited enhanced photocatalytic owing to the high surface area and small TiO2 crystallite size. A series of dynamic degradation experiments were conducted to investigate the effect of various operating parameters on acetone and p-xylene adsorption/degradation performances of the composite. The results illustrated that when the relative humidity (0–70%), gas flow rate (1–4 L/min), and VOC concentration (10–40 ppm) were set as the low values, the high total organic carbon degradation rate could be acquired. The total organic carbon degradation rate reached to a high value when the composite dosage was 3.76 mg/cm2. With the increase of light intensity (0.48–1.33 mW/cm2), the total organic carbon degradation rate presented an upward trend and then kept stable. The absorbent photocatalyst hybrid TiO2/diatomite composite could be the promising VOC purification materials.

The rapid expansion of oil sands activities and massive energy requirements to extract and upgrade the bitumen have led to a need for more comprehensive understanding of their potential environmental impacts, particularly on air quality. There are many oil sands developments and natural sources (point, area and mobile) that generate significant emissions, including nitrogen (NO2) and sulphur oxides (SO2), carbon monoxide (CO), and particulate matter. These chemicals are known to affect human health and climate. Thus an environmental monitoring program that measures the ambient air quality is needed to understand air pollutant emissions, their chemical transformation in the atmosphere, long‐range transport and subsequent deposition to the local and regional environment. Several studies have been conducted to understand the impact of the oil sands projects on the air quality over Alberta using ground-based measurements. However, data from these measurements are limited in spatial coverage as they reflect local air quality and cannot provide information about the overall regional air quality. A complementary approach to ground-based measurements is satellite-based monitoring which can provide large spatial and vertical coverage and allow monitoring of local and regional air quality. The objective of this report is to review available remote sensing technologies for monitoring and understanding the tropospheric constituents in the atmosphere, and potential use for monitoring the air quality over the oil sands region. The report includes a summary of the basic principles of remote sensing using satellites for tropospheric composition measurements; a detailed description of the instruments and techniques used for atmospheric remote sensing from space; demonstration of the key findings and results of using satellite data for air quality application; a brief summary of future missions; and, a case study to demonstrate the use of satellite data to study the impact of oil sands and other sources on carbon monoxide levels over Alberta. The science of atmospheric remote sensing has dramatically evolved over the past two decades and proved to be capable of observing a wide range of chemical species (e.g., aerosols, tropospheric O3, tropospheric NO2, CO, HCHO, and SO2) at increasingly higher spatial and temporal resolution. The integrated use of ground-based and satellite data for air quality applications has proven to be of enormous benefit to our understanding of the global distribution, sources, and trends of air pollutants. Despite the significance of using satellites in characterizations of air quality, there is limited research on using satellite-based remote sensing technology over Alberta. As satellite-based techniques now provide an essential component of observational strategies on regional and global scales, it is recommended to integrate data from satellite, and ground-based measurements as well as chemical transport models for air quality monitoring. This report provides an in depth review of the developments in the atmospheric remote sensing area that may support air quality management, policy, and decision makers at the national, and regional level to take actions to control the exposure to air pollution.

The overall goal of this project is to better understand the advantages and limitations of air emission pollutant characterization and monitoring techniques from area sources. This will allow for the selection of current technologies that are most suitable for measuring fugitive emissions of air pollutants from oil sands tailings ponds. The project consists of the following tasks: Task 1: Review concentration measurement technologies for volatile organic compounds (VOCs) reduced sulphur compounds (including H2S), and CH4. Task 2: Review flux measurement technologies that are used or can be used to measure air pollutant emissions from oil sand tailing ponds. Task 1: Review concentration measurement technologies for volatile organic compounds (VOCs), reduced sulphur compounds, and CH4 Methodology A review was conducted to determine the available technologies for characterizing and measuring the flux of each of the three groups of pollutants (VOCs, reduced sulphur compounds, and CH4). The review of the technologies included the following: a short description of the technology and its operating principle; instrument sensitivity (detection limit); advantages and limitations of the technique (performance, versatility, reliability); and cost, whenever possible. Costs do not include the labour to collect samples or the costs involved in running the analyses at other laboratories, as these are variable. However, such costs should be weighed when considering the application of the different technologies. Sample collecting procedures are important as they may affect the accuracy and precision of the technologies; these techniques are generally standard and have not been focused on for this report. Technologies for VOC Characterization The technologies for VOC characterization were classified into conventional analytical technologies (based on laboratory and field techniques) and remote sensing monitoring technologies (based on field techniques). The following technologies have been reviewed and assessed: • Conventional Analytical Technologies o Flame Ionization Detection (FID) o Infrared (IR) Absorption Spectroscopy o Photo Ionization Detection (PID) o Gas Chromatography-Mass Spectrometry (GC-MS) o Proton-Transfer-Reaction Mass Spectrometry (PTR-MS) o Fourier Transform Infrared (FT-IR) Spectroscopy • Remote Sensing Monitoring Technologies o Open Path Fourier Transform Infrared (OP-FTIR) Spectroscopy o Differential Optical Absorption Spectroscopy (DOAS) o Tunable Diode Laser Absorption Spectroscopy (TDLAS) o Differential Absorption LIDAR (DIAL) o Solar Occultation Flux (SOF) Technologies for Reduced Sulphur Compound Characterization The technologies for reduced sulphur compound characterization were classified into conventional analytical technologies (based on laboratory techniques and field techniques) and remote sensing monitoring technologies (based on field techniques). The following technologies have been reviewed and assessed: • Conventional Analytical Technologies o Flame Photometric Detection (FPD) o Pulsed Flame Photometric Detection (PFPD) o Sulphur Chemiluminescence Detection (SCD) o Photo Ionization Detectors (PID) o Ultraviolet (UV) Spectrometric Detection • Remote Sensing Monitoring Technologies o Tunable Diode Laser Absorption Spectroscopy (TDLAS) o Image Multi-Spectral Sensing (IMSS) o Differential Absorption LIDAR (DIAL) o Open Path Fourier Transform Infrared (OP- FTIR) Spectroscopy Technologies for CH4 Characterization The technologies for CH4 characterization were classified into conventional analytical technologies (based on laboratory and field techniques) and remote sensing monitoring technologies (based on field techniques). The following technologies have been reviewed and assessed: • Conventional Analytical Technologies o Infrared (IR) Absorption o Mid-Infrared Polarization Spectroscopy o Photoacoustic Absorption Spectroscopy (PAS) o Solid State (SS) sensor o Wavelength Modulation Spectroscopy (WMS) • Remote Sensing Monitoring Technologies o Radial Plume Mapping (RPM) o Differential Optical Absorption Spectroscopy (DOAS) o Correlation Spectroscopy (CS) o Airborne Natural Gas Emission Lidar (ANGEL) Task 2: Review flux measurement technologies that are used or can be used to measure emissions from air pollutant emissions and greenhouse gases from oil sand tailing ponds. The technologies for measuring concentration fluxes of fugitive emissions within the atmosphere were also classified into conventional analytical techniques and remote sensing monitoring technologies (all based on field techniques). The following technologies have been reviewed and assessed: • Conventional Analytical Techniques o Chamber Methods o Eddy Covariance (EC) o Eddy Accumulation and Relaxed Eddy Accumulation o Flux Gradient Techniques o Mass Balance Techniques o Tracer Gas Method • Remote Sensing Monitoring Technologies o Solar Occultation Flux (SOF) o Nocturnal Boundary Layer Box Method o Radial Plume Mapping (RPM) The report concludes with recommendations for technologies to use for monitoring air emissions from oil sands tailings ponds based on the following factors: spatial coverage, quantification of the pollutants, determination of emission factor, characterization of VOC speciation, and frequency of monitoring. For a variety of reasons there may not be one technology that is best suited for emission measurements across the oil sands region, and it is important to understand the different advantages and limitations of the technologies when selecting an option and interpreting the resulting data.