Precipitation and deposition of paraffin wax in pipelines and tubing are critical complications in the development of crude oil in oil and gas industry. Most new information on paraffin wax is dispersed in literature or exists in crania of experts like tacit knowledge. This review paper aims at disseminate the information; bridge some knowledge-gaps by giving a comprehensive review of chemistry of paraffin wax precipitation and deposition; causes and mechanisms as well as detection. It also discusses general effects of paraffin wax deposition and management, including types of remediation measures. Additionally, it sums up a conclusion and proffer valuable recommendations.

Organics and trace metals of the resin fraction of Nigerian crude oil were analysed in order to characterise the fossil fuel. The crude oil samples were deasphaltened by n-pentane, while maltene fraction was fractionated into its components (saturates, aromatics and resin) using column chromatography. The organic compounds and elemental concentrations of the resin fraction were investigated using Fourier Transform Infrared Spectroscopy and Inductively Coupled Plasma Optical Emission Spectrometry respectively. The infrared spectra showed characteristic bands containing polar functional groups expected confirming that the resin was purely eluted. The elemental concentrations were found to be high compared to other fractions and was confirmed by their T-test values. Zinc had the highest mean concentration of 32.13 ± 35.66 mg/kg, while Mn had the least (1.14 ± 0.17 mg/kg). Results indicated that processing of the crude oil resin may cause catalyst poisoning/fouling, corrosion of equipment/pipelines. Therefore, adequate consideration of these trace metals must be taken before processing.

Studies of organics and trace metals of the resin fraction of Nigerian bitumen were carried out with an opinion to establish the environmental consequences of the fossil fuel and as well as characterize them. Bitumen samples were extracted from oil sands via Soxhlet extraction procedure using toluene as the extracting solvent. The bitumen samples were deasphaltened to obtain maltene by dissolving the samples in n-pentane (1:40). Column chromatography was used to fractionate the maltene into its components (saturates, aromatics, and resin) using silica gel as adsorbent and dissimilar solvents of varying polarity (n-hexane for saturates, toluene for aromatics, and methanol for resins). The organic compounds of the resin fraction were examined using Fourier Transform Infrared Spectrophometry (FTIR) and the elemental concentrations were determined using Inductively Coupled Plasma Optical Emission Spectrophotometry (ICP-OES). The infrared spectra of all the resin samples presented distinctive bands including expected polar functional groups which confirmed that the resin was cleanly eluted from the bitumen samples. The concentrations of the analyzed trace metals in the resin fraction were found to be high compared to other fractions and this was confirmed by their T-test values. Fe had the highest average concentration of 34.81 ± 14.37 mg/kg and a range of 19.35–47.48 mg/kg, while Mn had the least mean concentration of 0.94 ± 0.71 mg/kg and a range of 0.35–1.88 mg/kg. The result of cross-plot analysis revealed that resin fraction has strong and positive inter elemental correlation with the NSO and asphaltene fraction of the same bitumen samples. The overall results indicated that processing of the bitumen and/or its resin may cause catalyst poisoning and fouling, corrosion of equipment and pipelines, and particulate emissions into the environment and therefore adequate demetalisation of the fossil fuel must be done before processing.