The Great Transformation of Energy: The Foresight and Innovation of Academician ZHAO Dongyuan
How did time begin?
The Big Bang theory suggests that approximately 13.8 billion years ago, our current universe emerged from a singularity with infinite density, infinite temperature, and infinitesimal volume. The renowned physicist Stephen Hawking once put forward a bold idea: time and space were born simultaneously at the moment of the Big Bang. Before the Big Bang, the concept of time did not exist.
According to the Big Bang theory, the origin of humanity and the origin of the universe share the same starting point. The world before this was a void. At this starting point of the Big Bang, an infinite amount of energy began to expand. In the first few microseconds, the temperature of the universe soared to trillions of degrees. At this time, the universe resembled a searing "particle soup" filled with elementary particles such as quarks, gluons, and leptons. These particles were constantly created and annihilated under extremely high energy. During this stage, matter and energy were transformed into each other, and the entire universe was in a dynamic equilibrium where pure energy and matter intertwined. Shortly after the Big Bang, during the inflationary period, quantum fluctuations were amplified, becoming the origin of the formation of the universe's structure. After several evolutionary processes, approximately 10 seconds later, stable atomic nuclei of hydrogen and helium, the chemical elements we are familiar with, finally formed.
When we look back at the origin of the universe, at that moment known as the Big Bang, it seems that all energy and matter suddenly emerged from nothingness and then constructed the real - world we all live in today. Therefore, the world we live in is essentially an energy - based world. In fact, energy and resources are so crucial to modern society that they can almost be regarded as the driving force and source of contemporary civilization, the material foundation for human activities, and an important pillar for the economic development of modern society.
The Trilemma of New Energy - Still Dependent on Primary Energy in the Long Run
Classified by their basic forms, energy can be divided into primary energy and secondary energy. Primary energy refers to natural energy, which exists ready - made in nature. Secondary energy refers to energy products converted from primary energy, such as electricity, gas, steam, and various petroleum products. Primary energy can be further divided into renewable energy (such as hydropower, wind energy, and bioenergy) and non - renewable energy (such as coal, petroleum, natural gas, and oil shale). The mainstream energy sources we currently use are mainly non - renewable primary energy sources, such as petroleum, natural gas, and coal. They are all related to carbon and are called carbon - based energy.
By carefully observing the global distribution of the three major energy sources, we must recognize that currently, over 80% of energy still depends on the three giants of carbon - based fossil fuels: coal, petroleum, and natural gas. We are and will remain dependent on primary energy for a long time. Therefore, from the general trend of energy consumption, carbon - based energy remains the mainstream in the face of renewable energy.
Of course, the proportion of renewable energy is currently on the rise, with 45% of the growth coming from China. However, to be realistic, its development still faces many challenges. Currently, the efficient and clean use of primary energy is an inevitable path. The whole world is promoting the structural optimization among various primary energy sources. In particular, the fields of chemical engineering and materials development we are engaged in are important supports for the efficient and clean use of primary energy.
In today's large energy - consumption market, petroleum has long maintained its position as the mainstream energy source. As of the end of 2020, the world's proven oil reserves were 173.2 billion barrels. According to the reserve - to - production ratio in 2020, the world's petroleum can sustain the current production and consumption for over 50 years. Is there a possibility of an oil energy crisis in the future? I have doubts about this statement because new large - scale oil fields have been continuously discovered around the world in recent years. Once, Saudi Arabia had the largest oil reserves in the world, but in 2001, Venezuela's total oil reserves exceeded those of Saudi Arabia. Since the early 20th century, large - scale oil fields have been successively discovered in Alberta, Canada, and Iran. Currently, although the world's energy consumption is highly dependent on petroleum, there is no shortage in the future. In my opinion, the so - called energy crisis does not hold water.
Building a green and low - carbon energy system led by fossil fuels is the fundamental requirement for global sustainable development and the material foundation for a community with a shared future for mankind. From the general trend of energy, the energy consumption demand is increasing, but at a slower rate. The proportion of natural gas and renewable energy is increasing, and carbon emissions are continuously decreasing. In terms of energy source selection, each country has its own focus: in North America, the United States focuses on unconventional natural gas/oil; in Europe, the emphasis is on renewable energy. Germany has shut down its nuclear power plants and focuses on the development of wind and solar energy, while France mainly relies on nuclear power; in South America, Brazil takes bioenergy as its development direction. Regarding carbon dioxide, which has been widely criticized, 80% of carbon dioxide emissions come from energy. Taking coal as an example, burning one ton of coal produces 3.7 tons of carbon dioxide. However, we also need to realize that crops cannot survive without carbon dioxide. A good harvest in agriculture requires carbon dioxide, and plants need to carry out photosynthesis to produce the glucose and proteins we need. Whether carbon dioxide is the main cause of the "greenhouse effect" is also debatable. Carbon dioxide is the most abundant greenhouse gas, accounting for approximately 0.03% of the total atmospheric volume. However, other types of gases can also cause the greenhouse effect, and some of them have a stronger greenhouse effect than carbon dioxide. For example, each molecule of methane absorbs more than 20 times the heat of carbon dioxide, and nitrous oxide (N₂O) is even higher, 270 times that of carbon dioxide. A new analysis of industrial methane emissions published by the International Energy Agency (IEA) found that the concentration of methane in the atmosphere has almost tripled since the pre - industrial era - much more than the increase in carbon dioxide, the most important gas.
As for the energy situation in China, it can be said that there are both long - term concerns (shortage of energy resources and serious environmental pollution) and immediate worries (insufficient energy supply and low energy efficiency). China is the world's largest energy consumer. In 2023, China's external dependence on petroleum reached 77% - 27% above the red line, and its external dependence on natural gas was 44%. At the same time, China's energy structure needs improvement. Coal remains the main fuel, accounting for 56% of energy consumption in 2022. China's per - capita energy resource possession is also relatively low.
This high degree of external dependence makes China's energy supply severely affected and restricted by geopolitical risks. Many oil - exporting countries generally face the problem of unstable political situations, which may disrupt China's overseas oil and gas supply.
In addition, 70% of China's imported crude oil has to pass through the Malacca Strait, known as the "energy choke - point". Geopolitical disputes may lead to the scramble for control of this sea area, thus threatening China's oil and gas imports. The outbreak of the Russia - Ukraine conflict in 2022 triggered a sharp rise in international natural gas prices, which also had a huge impact on China's energy supply security. It can be said that geopolitical factors have become a weak point in China's energy security. This requires us to have a sense of crisis and maintain a bottom - line mindset.
At the same time, achieving the dual - carbon goal in China is a tough battle. To achieve the goal of carbon neutrality, the economic and social conditions need to reach a certain level. Developed economies generally achieved carbon peaking when their per - capita GDP was between $20,000 and $25,000. Currently, China's per - capita GDP is only $10,000, and energy consumption is still on the rise. There is no time to repeat the process of developed countries where "per - capita energy consumption first increases rapidly, then remains saturated for a long time, and finally gradually decreases". We cannot follow the old path of de - industrialization in the West. The dual - carbon goal is currently forcing an energy and industrial technology revolution.
In addition, although the new renewable energy is developing rapidly, it is still in its "infancy" and cannot shoulder the future energy burden in the short term. We all know that new energy currently faces a "trilemma": it cannot simultaneously meet the three requirements of stable supply, environmental friendliness, and low cost. Debbie Niemeier, a professor of civil and environmental engineering at the University of California, Davis, once pointed out that at the current research and development speed, it is estimated that 90 years after the depletion of global oil resources, alternative technologies will mature. Therefore, it is undeniable that while renewable energy is developing rapidly, fossil fuels will remain the main energy supply in China for a long time. Therefore, how to achieve the efficient and clean use of fossil fuels is also the focus of the future energy technology revolution.
Taking petroleum as an example, we need to make full use of crude oil through technological progress. From the production of clean oil products to the efficient use of heavy oil, innovation in chemical processes will be the key. At the same time, in terms of coal utilization, we also need to vigorously promote high - efficiency combustion, high - efficiency power generation, and poly - generation technologies such as the integrated gasification combined cycle power generation system (IGCC), and cooperate with carbon dioxide capture and underground storage to minimize emissions.
The Energy Revolution Depends on New Materials Technology - The Power of Chemists
In the global energy landscape, a shocking figure lies quietly in the statistical report: unconventional oil resources such as heavy oil, extra - heavy oil, and oil sands account for 70% of the world's total crude oil reserves! These "heavy" resources are like sleeping giants, containing huge amounts of energy, but have long been neglected due to the great difficulty in extraction and conversion. At the same time, in the process of conventional oil refining, a large amount of heavy oil and residue are produced as "by - products", and their efficient utilization has always been a difficult problem for the petrochemical industry.
Let's start with a set of data to understand the severity of the problem. Crude oil can be divided into four grades according to its boiling range: light crude oil (boiling point less than 200°C), medium - crude oil (boiling point less than 350°C), heavy crude oil (boiling point greater than 350°C), and residue (boiling point greater than 500°C). In China's crude oil structure, the average content of residue is as high as 47.8%, and in some crude oils, the residue content even reaches 65.8%. What does this mean? China's annual crude oil consumption reaches 700 million tons, and its external dependence is as high as 77%. Calculated according to the average ratio of 47.8%, China produces more than 300 million tons of residue every year, but the clean utilization capacity is only 49 million tons, with a utilization rate of less than 20%. In other words, more than 80% of heavy resources cannot be effectively utilized, and most of them can only be used at a lower level, such as for paving asphalt. This is undoubtedly a huge waste of resources. Facing this reality, we chemists and materials scientists did not choose to avoid it. Instead, we delved into the microscopic world at the molecular scale and used our wisdom to "create pores" in the invisible dimension, finding a path for the light conversion of these heavy resources.
To understand how chemists solve this problem, we need to review the development history of catalyst technology. This is an evolutionary history of constantly breaking through scale limitations. In the 1960s, the application of Y - type zeolite (pore size about 0.8 nanometers) opened the era of catalytic cracking; in the 1970s, ZSM - 5 molecular sieve (pore size about 0.5 nanometers) achieved a breakthrough in shape - selective catalysis; in the 1980s, TS - 1 molecular sieve (pore size about 0.6 nanometers) brought a green "zero - emission" process. These technological advancements brought leap - forward economic benefits, but also exposed a key problem: the pore size of traditional microporous molecular sieves is too small. When dealing with large molecules in heavy oil and residue, it is as difficult as trying to get an elephant through a needle's eye. In the 1990s, the emergence of mesoporous molecular sieves we pioneered changed all this. Mesoporous materials with a pore size between 2 - 50 nanometers provide enough "space" for large molecules. This is not just a simple increase in size but a fundamental change in the catalytic concept.
I label myself as a "pore creator". I have a professional habit. When I see others synthesize a new compound, I always instinctively wonder: Can I create pores on it? It's like using a chisel to create pores in the invisible microscopic world. These "pores" are not natural but "grown" through chemical reactions, with a diameter between micropores (less than 2 nanometers) and macropores (greater than 50 nanometers). The surface area of a small stone is only a few square centimeters, but when one gram of mesoporous material is spread out, its surface area can reach hundreds or even thousands of square meters, large enough to play football on.
The uniqueness of mesoporous materials lies not only in their large specific surface area but also in their adjustable pore size and excellent pore connectivity. By adjusting the structural properties of the materials, a customized reaction environment can be provided for molecules of different sizes, greatly increasing the contact opportunities between active sites and reactants. On the basis of mesoporous materials, we further developed a core - shell nanostructure. This design organically integrates the different functions of multiple components, like a miniature chemical plant.
The core - shell structure has four unique advantages: first, it enables the integration of multiple functions, allowing different reactions to occur in different regions of the same particle; second, it maximizes the activity of the shell layer, saving precious metal raw materials; third, it has a strong interfacial synergistic effect; finally, it has a rich variety of structures, and complex morphologies such as hollow structures and yolk structures can be designed.
In the application of heavy oil catalytic cracking, this design shows amazing wisdom: heavy oil is first decomposed into smaller fragments under the action of the outer shell material with a large pore size and weak acidity. Then, these fragments enter the inner layer material with a small pore size and strong acidity, and are further cracked into small - molecule olefins and alkanes, ultimately producing high - quality clean fuel.
After ten years of unremitting efforts, we successfully created a hierarchical - pore core - shell micro - mesoporous catalyst (named the FC series by Sinopec). The FC - 38 molecular sieve has achieved kiloton - scale production, which marks a huge leap from gram - scale preparation in the laboratory to ton - scale production in industry. In the 560,000 - ton/year hydrocracking unit of Qilu Petrochemical, compared with the traditional UOP catalyst, the yield of middle distillates of this new catalyst increased by 1.5%. Behind this seemingly small increase lies huge economic value. If this technology is promoted nationwide, it can increase the production of aviation kerosene and diesel by 1.5 million tons per year. Calculated at a price of 6,000 yuan per ton, this alone can create 9 billion yuan in direct economic value.
In terms of residue treatment, we also developed a more advanced ebullated - bed technology. This technology achieved the large - scale preparation of micro - spherical ebullated - bed catalyst carriers