Rate coefficients are reported for the gas-phase reaction of the hydroxyl radical (OH) with 1,1-dichloroethylene (k₁) and trans-1,2-dichloroethylene (k₂) over an extended temperature range at 740 ± 10 Torr in a He bath gas. Absolute rate measurements were obtained using a laser photolysis/laser-induced fluorescence (LP/LIF) technique under slow flow conditions. Rate measurements for k₁ exhibited complex behavior with negative temperature dependence at temperatures below 640 K, a rapid falloff in rate between 650 and 700 K, and positive temperature dependence from 700 to 750 K. The simple Arrhenius equation adequately describes the data below 640 K and above 700 K and is given (in units of cm³ molecule^-1 s^-1) by k₁(291−640 K) = (1.81 ± 0.36) × 10^-12 exp(511 ± 71)/T and k₁(700−750 K) = 3.13 × 10^-10 exp(−5176/T). Rate measurements for k₂ also exhibited complex behavior with a near-zero or slightly negative temperature dependence below 500 K and a near-zero or slightly positive temperature dependence above 500 K. The modified Arrhenius equation adequately describes all of the data and is given (in units of cm³ molecule^-1 s^-1) by k₂(293−720 K) = (9.75 ± 1.14) × 10^-18 T^{1.73± 0.05} exp(727 ± 46)/T. Error limits are 2σ values. The room-temperature values for k₁ and k₂ are within ±2σ of previous data using different techniques. The rate measurements were modeled using QRRK theory. OH addition to the unsubstituted carbon followed by adduct stabilization describes the low-temperature measurements for k₁. Analysis of equilibration in this system yields a C−O bond dissociation enthalpy of 32.8 ± 1.5 kcal mol^-1 at 298 K, a value confirmed by ab initio calculations. OH addition followed by Cl elimination described the experimental data for k₂. Ab initio based transition state calculations for the H atom abstraction channel indicated that this mechanism is consistent with the rate measurements for k₁ above 700 K. The H abstraction channel for k₂ could not be observed because of the presence of a more rapid Cl elimination channel at elevated temperatures. H abstraction is predicted to be the dominant reaction channel for both k₁ and k₂ at flame temperatures.

In this work, the performance of selected ionic liquid-water mixtures was investigated for an acetone cooling application in a process plant using a double pipe heat exchanger. Cooling media such as river water and ionic liquid-water mixtures were compared, specifically water-saturated quaternary phosphonium-based carboxylate ionic liquids were considered in this work. Ionic liquids generally have high thermal stability, resist degradation, and provide higher temperatures at low vapor pressures and for these reasons, ionic liquids can be a good substitute for conventional heat transfer fluids. At each condition, the performance of the ionic liquid mixture was compared with that of water. For the designated cooling application, the performance of water was much better than the ionic liquid mixtures.

An Environmental Management System (EMS) is critical for oil and gas companies to reduce their pollution activities. However, only a few organizations have adopted such a system. This study evaluates the environmental outcomes of the oil and gas industries, focusing on a comparison between organizations that have adopted EMS and those that have not. The analysis carried out highlighted significant differences in Environmental Performance (EP), Employee Satisfaction (ES), Operational Improvement (OI), occupational Health and Safety (HS), and Competitive Advantage (CA) between organizations which have adopted EMS and those that have not. Data collected from oil and gas organizations in Saudi Arabia revealed that EMS adoption significantly enhances the EP, OI, and HS metrics while contributing to reduced carbon emissions and improved resource management. However, organizations that have not adopted EMS showed higher ES, indicating possible issues in EMS implementation strategies. The findings stress the essential role of EMS in achieving the United Nations Sustainable Development Goals (SDGs), especially in fostering responsible production, clean energy, and climate action. These insights offer valuable guidance for policymakers and industry leaders aiming to align industrial practices with sustainability goals.

Biodiesel production is rapidly moving towards the mainstream as an alternative source of energy. Algae oil is one of the viable feed stocks among others to produce Biodiesel. However the difficulties in efficient biodiesel production from algae lie not in the extraction of the oil, but in finding an algal strain with a high lipid content and fast growth rate. This paper presents an experimental work performed to study the production of biodiesel from local algae strains in Al-Hassa territory of the eastern province in Saudi Arabia which was found to contain high lipid contents and show rapid growth. The collected results predict that those types of desert algae are promising and are considered to be a potential feedstock for biofuels.