Phenol and its compounds are highly toxic even in low concentration, and have become the subject of intense research during the last two decades. Effluents from industries such as oil refining, paper milling, olive oil extraction, wood processing, coal gasification and textiles and resin manufacturing and agro-industrial wastes discharge phenols at levels much higher than the toxic levels set for this compound. Advanced Oxidation Processes (AOPs) such as UV, UV-TiO2, UV-H2O2, O3 and UV-O3 have become popular in recent years as efficient treatment methods for recalcitrant compounds like phenol. The effect of microwave (MW) and combined MW-UV treatment on degradation of phenol was studied in aqueous solution in the presence and absence of TiO2 under controlled temperature conditions. It was found that the efficiency of MW and MW-UV processes for the degradation of phenol was less than 10% after 120 minutes of treatment. However, the efficiencies of MW-TiO2 (hydrothermal) and MW-TiO2 (sol-gel) were slightly more than those of the above processes at 12 to 15% after 120 minutes, which might be due to adsorption of the phenol on the surface of TiO2 particles. It also was observed that MW-UV-TiO2 was superior to any other process studied for the degradation of phenol. At natural pH, the degradation efficiency of MW-UV-TiO2 (HT) on 1500 ppm of phenol in water was 23%, and for MW-UV-TiO2 (SG) it was 20%. Hence, it can be concluded that the catalyst (TiO2) prepared by the hydrothermal (HT) method had better catalytic activity than TiO2 prepared by the sol-gel (SG) method, which might be due to its structural and optical characteristics. Of the two developed reactors which are MW and a combined MW-UV reactor, MW-UV combined with TiO2 could be used for most successful degradation of phenol.

Microwave dielectric resonators (DRs) are being widely used in microwave telecommunication devices owing to their excellent characteristics of suitable dielectric constant, good temperature stability, and low dielectric loss. In this study, the crystalline phase and the microwave dielectric properties of the (1-x)Al2O3 - xTiO2 (x=0.08, 0.12, 0.16) compositions with 2wt%, 4wt%, 6wt%, and 8wt% MgO-CaO-Al2O3-SiO2 (MCAS) glass addition have been investigated. By combining the material Al2O3 with negative temperature coefficient of the resonant frequency (£nf = -55 ppm/¢J) and the material TiO2 with positive £nf value (£nf = +450 ppm/¢J), it is desired to produce the ceramics with £nf ~0 ppm/¢J. The MCAS is used as liquid-phase sintering aid to lower down the sintering temperature. In the MCAS-doped (1-x)Al2O3 - xTiO2 system, the Al2TiO5 phase starts to appear at about 1250¢J, and then the crystalline intensity of Al2TiO5 phase increases with the increase of sintering temperatures and MCAS glass content, until the temperatures that TiO2 is consumed. As the sintering temperature increases, the maximum dielectric constants and Q¡Ñf values can be obtained at 1250¢J, and the £nf values shift from positive to negative. The optimum £nf value of ¡V0.6 ppm/¢J exists in the 88mol%Al2O3 - 12mol%TiO2 composition with 2wt% MCAS addition and sintering temperature of 1300¢J. The MCAS content, TiO2 content, and sintering temperature will result in the variation of microwave dielectric properties. In this study, MCAS-doped (1-x)Al2O3 - xTiO2 system exhibits the microwave dielectric properties of¡G £`r=7~9.5, Q¡Ñf=6500~11000, and £nf = -60 to +40ppm/¢J. By adjusting the MCAS content, TiO2 content, and sintering temperatures, ceramics with good microwave properties can be obtained in the MCAS-doped (1-x)Al2O3 - xTiO2 system.

Efficient oil production and refining processes require the precise measurement of water content in oil (i.e., water-cut) which is extracted out of a production well as a byproduct. Traditional water-cut (WC) laboratory measurements are precise, but are incapable of providing real-time information, while recently reported in-line WC sensors (both in research and industry) are usually incapable of sensing the full WC range (0 – 100 %), are bulky, expensive and non-scalable for the variety of pipe sizes used in the oil industry. This work presents a novel implementation of a planar microwave T-resonator for fully non-intrusive in situ WC sensing over the full range of operation, i.e., 0 – 100 %. As opposed to non-planar resonators, the choice of a planar resonator has enabled its direct implementation on the pipe surface using low cost fabrication methods. WC sensors make use of series resonance introduced by a λ/4 open shunt stub placed in the middle of a microstrip line. The detection mechanism is based on the measurement of the T-resonator’s resonance frequency, which varies with the relative percentage of oil and water (due to the difference in their dielectric properties). In order to implement the planar T-resonator based sensor on the curved surface of the pipe, a novel approach of utilizing two ground planes is proposed in this work. The innovative use of dual ground planes makes this sensor scalable to a wide range of pipe sizes present in the oil industry. The design and optimization of this sensor was performed in an electromagnetic Finite Element Method (FEM) solver, i.e., High Frequency Structural Simulator (HFSS) and the dielectric properties of oil, water and their emulsions of different WCs used in the simulation model were measured using a SPEAG-dielectric assessment kit (DAK-12). The simulation results were validated through characterization of fabricated prototypes. Initial rapid prototyping was completed using copper tape, after which a novel reusable 3D-printed mask based fabrication was also successfully implemented, which would resemble screen printing if it were to be implemented in 3D. In order to verify the design’s applicability for the actual scenario of oil wells, where an oil/water mixture is flowing through the pipes, a basic flow loop was constructed in the IMPACT laboratory at KAUST. The dynamic measurements in the flow loop showed that the WC sensor design is also equally applicable for flowing mixtures. The proposed design is capable of sensing the WC with a fine resolution due to its wide sensing range, in the 80 – 190 MHz frequency band. The experimental results for these low cost and conformal WC sensors are promising, and further characterization and optimization of these sensors according to oil field conditions will enable their widespread use in the oil industry.