ROLE OF FLOW IMPROVERS ON THE WAX DEPOSITION OF BOMBAY HIGH CRUDE OIL DURING PIPELINE FLOW

Wax deposition behaviour of Bombay High crude oil before and after treatment with flow improvers has been studied under flowing conditions in a horizontal pipe and the effect of time, cold surface temperature. rate of cooling, flow rate and diluent on deposition have been determined. It is observed that the time to obtain equilibrIUm wax deposition and the quantity of deposits are much less in additive treated crude oil compared to untreated crude oil under identical conditions

Thermal degradation processes in polysulfide copolymers investigated by direct pyrolysis mass spectrometry and flash pyrolysis-gas chromatography/mass spectrometry

This is the first report on the analysis of random block polysulfide copolymers containing different amounts of repeating units in the copolymer backbone, which has been studied by direct pyrolysis mass spectrometry (DPMS) and by pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). The homopolymers such as poly(ethylene sulfide) (PES), poly(styrene sulfide) (PSS), and two random copolymers, viz., poly(ethylene sulfide(x)-co-styrene sulfide(y)) [copolymer I (x = y = 0.5) and copolymer II (x = 0.74, y = 0.26)] were investigated by both DPMS and Py-GC/MS (except copolymer II) techniques. In the case of copolymer I, the thermal degradation products of SE1, SE2, S-2, and S2E (S = styrene sulfide, E = ethylene sulfide) were detected in DPMS, whereas the formation of SE1 and SE2 were observed by Py-GC/MS technique. However, for copolymer II, SE3 was also found along with SE1, SE2, S-2, and S2E in DPMS. The formation of additional product (SE3) observed in copolymer II could be due to an increase in the block length formed during copolymerization. Further, a comparative study on thermal degradation of PES, poly(ethylene disulfide) (PEDS), and poly(ethylene tetrasulfide) (PETS) were investigated by Py-GC/MS. The pyrolysis products detected by both DPMS and Py-GC/MS indicates that the thermal decomposition of these polymers yield cyclic sulfides through an intramolecular exchange or by backbiting processes. The linear products with thiol and vinyl groups were also observed by Py-GC/MS along with the cyclic products via carbon hydrogen transfer reaction

Influence of waxes on the flow properties of Bombay high crude

Waxes present in crude oil are considered to be responsible for its poor flow properties. Bombay high crude is very waxy and has a pour point of + 30 °C. The influence of nature and concentration of waxes on some of the flow properties, namely pour point, plastic viscosity and yield stress, of dewaxed Bombay high crude have been determined. The hard wax components present in the crude do not appear to significantly influence the low temperature rheology of the crude oil, but do contribute to sludge formation

Role of choline formate ionic liquid in the polymerization of vinyl and methacrylic monomers

Polymerizations of vinyl and methacrylate monomers (2-hydroxyethyl methacrylate, styrene, and methyl methacrylate) were carried out in a choline formate ionic liquid at room temperature without the addition of peroxide-based initiators. Choline formate acted as both an initiator and a solvent and produced high-molecular-weight polymers. Gel permeation chromatography and electron paramagnetic resonance measurements indicated that the polymerizations predominantly occurred by a free-radical mechanism. This method of polymerization provides an alternate route to eliminate the use of toxic initiators and solvents