Oil plays an indispensable role in the ever-increasing global energy economy. Over the past 20 years, oil demand has steadily increased from 60 to 84 million barrels per day. 1 With the explosive expansion of consumption and industry in emerging countries like China and India in the early years of the 21st century, the global average annual growth rate of demand for crude oil has grown to 3.4%. 2 The reduction in conventional oil and gas resources has led to the promotion, development, and utilization of unconventional resources, particularly heavy oil and oil sands. Heavy oil accounts for half of the world's crude oil reserves, and Canada has the world's largest heavy oil and bituminous production, with approximately 1 trillion and 700 billion barrels of heavy oil and asphalt, respectively. 3,4 Crude oil from reservoirs usually consists of a series of hydrocarbons, such as olefins, naphthenic hydrocarbons, aromatic compounds, phenols, carboxylic acids, and some impurities (such as water, sediments, and a small amount of