Polypropylene (PP) is a commodity material that has been increasingly used in different industries in the past two decades due to its versatile properties when enhanced with additives. Homo polypropylene, in general, has weak mechanical properties and limited chemical resistance; thus, using a different type of fillers to adjust such properties to fit the required applications opened a large market for this commodity. Understanding the interface constituent between the polymer matrix and the added filler and the nucleation behavior is a key to fine control of the enhancement of PP properties. In this study, PP was incorporated with nano calcium carbonate (CaCO3) at 2 and 5 wt% in the presence of maleic anhydride (MAH) to overcome the weak interface due to low polymer polarity. The mix was compounded in a twin screws extruder at a temperature range of 180–200 °C ; then, the prepared samples were left to dry for 24 h at 25 °C. Nuclear Magnetic Resonance (NMR) was used to study the interface adhesion of the nanofiller and the curved revealed that at 2% of nano CaCO3 PP structure remained the same and the nano experienced good adhesion to the polymer matrix. The mechanical impact resistance results showed a real enhancement to the polymer matrix of the nanocomposite by 37%. Moreover, DSC results showed a faster crystallinity rate due to the nanofiller acting as a nucleating agent and rheology tests indicated that low content of nano additive (2%) has better processability behavior, with suitable viscosity complex values at high frequencies.

Selected apparent kinetic parameters such as rate constants and activation energies of the hydrodemetallation (HDM) and hydrodesulfurization (HDS) reactions were assessed for two Kuwaiti Residual oils using two types of commercial atmospheric residual desulfurization (ARDS) catalysts. The feeds investigated in the study were 360 °C+ cuts of Kuwait Export crude (KEC) and Kuwait Ratawi/Burgan crude (KHC). The catalysts used in the study were two different catalysts of a complete ARDS catalyst system (Cat-B) consisting of five different catalysts. Cat-BA is an HDM catalyst used in the front reactor of an industrial ARDS process to remove possible contaminants present in the feed, such as metals, sulfur, nitrogen, and to reduce the feed asphaltene content to lowest levels possible. Cat-BC is an HDS catalyst, usually employed in the middle reactors, mainly to reduce the feed sulfur content to the desired levels. Testing was performed using a bench scale unit that was equipped with three fixed-bed reactors working under trickle flow mode. The findings showed that KEC-AR is generally more reactive than KHC-AR, in terms of metals and sulfur removal over both catalysts. However, KHC-AR showed higher reactivity for sulfur removal over Cat-BA, although KHC-AR contains higher levels of sulfur and asphaltenes, in comparison to KEC-AR.

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A simple procedure is developed to determine the apparent rate constants, reaction orders, and activation energies of various hydrotreating reactions, such as the hydrodesulfurization (HDS), hydrodemetalation (HDM), hydrodenitrogenation (HDN), and asphaltene cracking (HDAsph) of hydrotreating catalysts loaded in multiple-reactor fixed bed units. The procedure is derived from the basic kinetic and engineering principles. The only required input parameters are the sulfur, vanadium, nickel, nitrogen, and asphaltenes contents in the feedstock and products, reaction temperatures, and liquid hourly space velocity (LHSV). These parameters are normally available from laboratories performing the kinetic studies. Since there is no correlation coefficient in the developed kinetic expression, the apparent reaction rate constant and activation energy for various hydrotreating reactions can be determined directly once the optimum value of the reaction order has been identified. To demonstrate how the procedure works, it has been applied to calculate the kinetic values published in the open literature. Excellent agreements are obtained. The procedure is further verified with kinetic parameters from experiments undertaken in our pilot plants. In some cases, kinetic values which were unable to be determined in our pervious studies can now be obtained. The overall absolute average deviation (AAD) is less than 10%.