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The article discusses the applicability of ZSM-5 additives on fluid catalytic cracking (FCC) units and propane dehydrogenation (PDH) units and in the balancing between matrix and zeolites and rare earth.

The article discusses the use of ZSM-5, a chemical belonging to zeolite family, at high concentrations to maximise propylene from the fluid catalytic cracking (FCC) unit to accommodate the need for increasing propylene demand. Topics discussed include Hydrogen transfer in the FCC, role of ZSM-5 on Liquified Petroleum Gas (LPG) yield and gasoline composition, and effects of ZSM-5 and base catalyst on gasoline composition.

The article offers information on the construction of new fluid catalytic cracking (FCC) units in growth regions including Asia and the Middle East as petrochemical FCC units to produce propylene from heavy residual feedstocks. It mentions that the demand for petrochemicals is increasing in Asia due to a shortfall in mixed xylenes and propylene production. It also mentions that propylene is a key chemical for plastics such as polypropylene, acrylonitrile and propylene oxide derivatives.

A two-step molten salt synthesis process was utilized to fabricate Sr3Ti2O7and SrTiO3.High aspect ratio SrTiO3seed crystals were developed by optimizing processing conditions such as temperature, salt-to-oxide ratio, and flux type in a systematic fashion. Sr3Ti2O7seeds were synthesized at temperatures ranging from 1050–1350°C, using salt-to-oxide ratios of 3:1, 1:1, and 1:3, and various salt types, including NaCl, KCl, and a 1:1 combination of NaCl and KCl. Sr3Ti2O7seeds synthesized at 1250°C with a 1:1 salt-to-oxide ratio in 100% NaCl salt resulted in a majority of higher aspect ratio platelets and elongated platelets as opposed to lower aspect ratio cubic-like and tetragonal-like morphologies. The seeds were 10–40 μm in length with aspect ratios of highly elongated platelets as high as 25:1. A second MSS step was used to synthesize SrTiO3seeds of the proper composition by TiO2addition to the Sr3Ti2O7seeds and heat treatment at 1100°C. These studies showed that highly anisotropic SrTiO3seeds could be produced at 1250°C using a 1:1 salt-to-oxide ratio in 100% NaCl flux. XRD studies of the resulting SrTiO3seeds revealed that the increase in aspect ratio for these particular seeds also resulted in the enhancement of (200) peaks, which are of major interest for texturing of PMN-PT.A two-step molten salt synthesis process was utilized to fabricate Sr3Ti2O7and SrTiO3.High aspect ratio SrTiO3seed crystals were developed by optimizing processing conditions such as temperature, salt-to-oxide ratio, and flux type in a systematic fashion. Sr3Ti2O7seeds were synthesized at temperatures ranging from 1050–1350°C, using salt-to-oxide ratios of 3:1, 1:1, and 1:3, and various salt types, including NaCl, KCl, and a 1:1 combination of NaCl and KCl. Sr3Ti2O7seeds synthesized at 1250°C with a 1:1 salt-to-oxide ratio in 100% NaCl salt resulted in a majority of higher aspect ratio platelets and elongated platelets as opposed to lower aspect ratio cubic-like and tetragonal-like morphologies. The seeds were 10–40 μm in length with aspect ratios of highly elongated platelets as high as 25:1. A second MSS step was used to synthesize SrTiO3seeds of the proper composition by TiO2addition to the Sr3Ti2O7seeds and heat treatment at 1100°C. These studies showed that highly anisotropic SrTiO3seeds could be produced at 1250°C using a 1:1 salt-to-oxide ratio in 100% NaCl flux. XRD studies of the resulting SrTiO3seeds revealed that the increase in aspect ratio for these particular seeds also resulted in the enhancement of (200) peaks, which are of major interest for texturing of PMN-PT.

A melt extraction technique has been used to produce fine fibers from three eutectic compositions in the systems of ZrO2‐Al2O3(ZA), ZrO2‐Al2O3‐SiO2(ZAS), and ZrO2‐Al2O3‐TiO2(ZAT). The liquid surface tension of these ceramics was measured by a new method and estimated to be in the range of 400‐567 mJ/m2at similar ∼2400°C. The wetting between Mo (the extraction wheel material) and liquid ceramics was found to be poor during transient wetting; however, fiber extraction was achieved due to the shear action induced by the wheel rotation. The difficulties in the extraction of ZA fibers at speeds of <1.5 m/s, and also the formation of air pockets on these fibers, are attributed to the poor wetting of the Mo wheel by the liquid ZA. In a wide range of wheel velocities, extracted fibers exhibited alternating sections of uniform diameter and Rayleigh waves, both being the largest for ZAS fibers at any speed. The Rayleigh wave dimensions varied considerably with speed whereas the dimensions of the uniform region of the fibers remained unchanged over the wide range of extraction speeds examined. The fiber dimensions are controlled by both surface tension and viscosity of the molten ceramics at the extraction temperature.

The article reports on bench-scale experiments that demonstrate the link between using additives in fluid catalytic cracking (FCC) and increased yields in petrochemicals. Topics discussed include the importance of using additives to optimize the fluid catalytic cracking process in addressing shortages of propylene, the renaissance being experienced by U.S.-based chemical companies, and two modes of FCC unit operations that can improve propylene yields.