Supercritical (sc) CO2 is by far the most commonly used supercritical fluid. Reasons for this are that it is inexpensive, non-toxic, has low critical constants (Tc = 304.20 K, Pc = 72.8 bar) and is environmentally benign. The major problem encountered when using sc CO2 is the low solubility of polar solutes. Hydrofluorocarbon (HFC) solvents such as difluoromethane (HFC 32) and 1,1,1,2-terafluor...

This paper describes results of a multiobjective comparative assessment of several established and emerging technologies for extraction of a natural antimalarial substance, artemisinin. Extractions by hexane, supercritical carbon dioxide, hydrofluorocarbon HFC-134a, ionic liquids, and ethanol were considered. Hexane extraction is an established technology and appears to be the most cost-effecti...

More than one year has passed since refrigerant for refrigerator was changed from CFC12 to HFC134a. Long term reliability of refrigerator in HFC134a refrigerant system is mainly dependent on lubrication of moving parts of compressor and clogging of capillary tube. To maintain better practical reliability in components in compressor such as refrigeration lubricant,metallic materials and motor in...

This article provides a theoretical energy performance and carbon footprint analysis of the hydrofluoroolefin HFO-1234ze(E) mixture R-515B as low global warming potential (GWP) refrigerants to replace hydrofluorocarbon HFC-134a in different heat pump applications. The reference configuration is single-stage cycle with an internal exchanger (IHX). In this way, impact IHX on medium moderately hig...

It is proven that fluorinated gases (F-gases) have a vast impact on climate change due to their high global warming potential. Hence, it imperative search for new molecules replace them in current applications, as well technologies capture, recover, and recycle F-gases avoid emissions the atmosphere. One of attractive this purpose absorb ionic liquids (FILs), given solubilization power. However...

The solubility of HFC 134a and HFC 152a in polystyrene melt was measured up to 800 psi at 150 C and 190 C. A magnetic suspension balance was used to experimentally measure the apparent solubility. The Simha-Somcynsky (SS) equation of state (EOS) was applied in the multi-components system to estimate the swollen volume. Consequently, the buoyancy compensation can be obtained to determine the sol...

Chlorofluorocarbons (CFCs) are stable in the atmosphere and may reach the stratosphere. They are cleaved by UV-radiation in the stratosphere to yield chlorine radicals, which are thought to interfere with the catalytic cycle of ozone formation and destruction and deplete stratospheric ozone concentrations. Due to potential adverse health effects of ozone depletion, chlorofluorocarbon replacemen...

Hydrofluoroalkane-134a (HFA) beclomethasone dipropionate (BDP) was formulated in a metered-dose inhaler (MDI) to deliver a particle size of 1.1 microm compared with 35 microns for currently marketed chlorofluorocarbon (CFC)-BDP products. Two phase I single-dose human deposition studies were conducted using technetium 99m-radiolabelled BDP in a press-and-breathe actuator without an add-on spacer...

Abstract Resistive Plate Chambers (RPC) are gasesous detectors employed at CERN LHC experiments thanks to their trigger performance, timing capabilities and contained production costs. High Pressure Laminate RPCs operated with a three-component gas mixture, made of 90–95% C $$_2$$ 2 </...