Into Unscientific Chapter 206

  Chapter 206 Old Su Shows His Power (6.2K)

   After deciding to overcome the barrier of transition metal catalysis first, Xu Yun and others quickly put on a set of standard lab coats.

  Students who have passed high school chemistry should know it.

  According to the periodic law of elements, people tend to look for catalysts in the area of ​​transition metals.

  For example, the catalyst for the synthesis of ammonia is an iron catalyst.

  Vanadium pentoxide is a catalyst for the synthesis of sulfuric acid and nitric acid.

  Alkenes and hydrogen addition mostly use Raney nickel and so on.

  Why do these transition elements and compounds often play the role of "moon old"?

  Here, let me explain a concept to you in human terms:

   Feedback π key.

  When a transition metal atom, that is, a coordination bond is formed between the central atom and the ligand.

  The coordinating atom will provide a lone pair of electrons to fill the empty orbital provided by the central atom.

   Thus forming a σ bond in the form of a coordination bond.

sometimes.

   Some electrons of the central atom may also fill in the empty orbitals of the ligand molecule.

   This is the feedback π bond.

   And in the process.

  The antibonding orbitals π2py* and π2pz* of the ligand molecules are empty.

   When it is used as a ligand.

  It can not only provide the lone pair of electrons to coordinate out, but also provide π antibonding empty orbitals to coordinate the electrons in.

  As long as the central atom and the ligand have lone pairs of electrons and empty orbitals, the prerequisites for coming and going are met.

   Coupled with the appropriate symmetry of the two, the feedback π bond is formed.

   See here.

  Smart students should understand.

   That's right!

  If the ligand molecule forms a feedback π bond with a certain transition metal atom, then its originally empty π antibonding orbital is filled with electrons.

  The bond order is negatively correlated with the number of electrons in the antibonding orbital.

  The more electrons are filled in the antibonding orbital, the smaller the bond level and the weaker the bond.

  N≡N, which was originally very strong, was weakened by the feedback bond, indicating that its chemical activity was greatly enhanced.

   In other words.

  If you want the ligand molecules to react again, it will be easier to proceed.

   This is the principle of transition element catalysis.

   Very simple and easy to understand.

  Xu Yun and his team used ruthenium as a transition metal in their laboratory, a metal with very stable properties and strong corrosion resistance.

   There is also a very special case of this thing:

   Its content in the earth's crust is only one part per billion, making it one of the rarest metals.

   But it is very cheap, and it is the cheapest metal among the platinum group metals.

   But cheap is cheap.

  Because its crystal structure is a hexagonal unit cell.

  It can only be used in the laboratory during the production of imidacloprid, and cannot be successfully used in industrial production.

   "So in the candidate scheme given, we append three metals, lanthanum, scandium, and gallium, and let Nutrien make the adaptation."

  Inside the laboratory.

  Xu Yun is introducing the relevant situation to Yu Yuanyong:

   "In the end, Nutrien gave a reply that lanthanum metal is also a type of transition metal catalyst with the highest comprehensive energy efficiency, and the actual operation effect after receiving the goods is also fully in line with expectations."

   "Of course, and because of this, their equipment quotation is also much higher than expected."

  In front of him, Yu Yuanyong nodded clearly.

   Among the three metals, lanthanum, scandium, and gallium, scandium is the most expensive.

  According to the current price.

  The price of one kilogram of 99.9% scandium is about 32,000 yuan.

   Next is gallium.

  The price per kilogram is 2805.

   Lanthanum is the cheapest.

  One ton is only more than 27,000 yuan, which is cheaper than the above two. I went to grandma's house.

at the same time.

  Gallium is also a choice with the best catalytic effect.

  However, it is the opposite of price and effect.

  The difficulty of mass production of the three metals in industrial production lines increases in turn.

  Equipment requirements are naturally the same.

  Think here.

  Yu Yuanyong picked up a report from the table beside him and turned to a certain page.

   Then he introduced to everyone:

   "Dr. Xu, to tell you the truth, we are currently stuck at the molecular sieve level of the catalyst."

  “Our team tried many methods, but unfortunately failed in the end.”

   "Don't talk about lanthanum, we haven't even made a breakthrough in scandium."

   “Because no matter the metal, the coordinating framework heteroatoms must be highly isolated in molecular sieves.”

"For example, the neighbors in Ti-O-Si are mainly Si-O-Si. On the other hand, Ti mainly exists in a four-coordinated manner. We must complete the atomic defect site reaction inside the container, but this is thermodynamically unfavorable. "

   Heard this.

  Lin Zhenhua on the side suddenly interrupted him and asked:

   "Xiao Yu, how did Nutrien complete this step? Can you learn from their thinking?"

  Yu Yuanyong shook his head, pointed to the computer at the other end and said:

   "Nutrien uses a chemical grafting patent, the whole link is connected by joints, and any point cannot be changed."

   "If it is a complete copy, not to mention the difficulty of the process, the patent protection will be difficult."

  “They can include FOERDT632 in the Wassenaar Agreement, but Dr. Xu and the others cannot copy the patent, otherwise it will be like handing the knife to others.”

  Lin Zhenhua opened his mouth when he heard the words, as if he wanted to say something.

   But in the end, there was still no sound, and it turned into a sigh.

  As Yu Yuanyong said.

  Huadun Biotechnology is not a small private workshop. Every step of Xu Yun and the others will be stared at with a magnifying glass, looking for your sore feet all the time.

  Once the production capacity of "One Mantis Killer" is improved.

   At that time, someone will inevitably instigate Nutrien to initiate a patent review and request to verify whether patent infringement is involved.

   Scoundrel?

   Of course rogue.

  The embargoed equipment on that end is not allowed to be imitated on this end, which is the extreme double standard.

  Is it legal?

  The answer is also yes.

  Even if Huadun Biotechnology has the support of HKUST and even the Academy of Sciences behind it, it will not help.

  Once this kind of thing happens, what awaits them is bound to be extremely severe punishment and crazy attacks from public opinion.

  So Nutrien and the people behind it will not be afraid of Huadun Biotechnology to replicate this chemical grafting process, maybe they would like you to do so.

   Then Xu Yun thought about it and came up with a new idea:

   "Director Yu, what do you think about using ion beam implantation?"

  Yu Yuanyong blinked:

   "Ion beam implantation?"

  Students who were ions in their previous lives should know this.

  The so-called ion beam implantation method.

   refers to the method of accelerating the metal ions generated by ionization in an electric field to form a high-speed ion beam and hitting the specified substrate.

  Due to the high speed of the ion beam, it can be implanted into the surface layer and lattice of the substrate, so as to achieve a regular effect.

  However, it is different from the chemical grafting method.

  Ion beam implantation is mostly used in the fields of physics and material science, especially in semiconductor surface modification and doping.

   Rarely used in catalyst preparation.

  Seeing that Yu Yuanyong was a little confused, Xu Yun patiently explained:

   "You think, the metal ions in the ion beam are all positively charged and will repel each other and separate."

   "So the metal ions injected into the matrix will basically remain in a highly isolated state."

   "Let's add a chemical intermediate to it, such as catechol or something. In this way, won't a Y-type molecular sieve come out?"

  Yu Yuanyong's eyes widened as he listened, and his mouth opened involuntarily, with a stunned expression.

   A few seconds passed.

  He suddenly made a fist with his right hand, and knocked heavily on the palm of his left hand:

   "That's right, we can completely force out the cations in the antibonding orbitals by introducing the same metal ions. Oh, look at my head, why can't I think of this layer?"

  Xu Yun laughed and said nothing when he heard the words.

  Ion beam implantation method.

   This is the last paper he published in his last life before leaving the field of scientific research, which involved the defect site reaction transition effect of vanadium metal, and involved molecular sieves.

  doi is. Keke, I can't say it, if I say it, I will lose my online name.

all in all.

  The last paper before leaving the circle is like your first love, and you may never forget it in this life.

  So after learning that Yu Yuanyong and the others were stuck on the molecular sieve, Xu Yun immediately thought of this idea.

  With Xu Yun's point, the next thing is very simple.

  The detection method of transition metal catalysis can be determined by using ultraviolet Raman spectroscopy in addition to the final product.

   Especially in terms of molecular sieves.

  Raman peak accuracy is even a little higher.

   So fast.

  Yu Yuanyong prepared for the detection link of Raman spectroscopy.

   Half an hour later.

  Yu Yuanyong's team finished preparations and officially started testing.

  Ten minutes after the start of detection.

   Transition metal heteroatoms begin to enter the molecular sieve framework.

at the same time.

  In the ultraviolet-visible absorption spectrum, the charge transfer transition absorption between the pπ of the skeleton oxygen atom and the dπ of the skeleton transition metal atom immediately appeared.

   Another twenty minutes passed.

   A report appeared on the equipment table in front of Yu Yuanyong.

   "The absorption peak is in the ultraviolet region of 200-350nm, and the center of the charge transfer transition absorption band is at 220nm"

  Yu Yuanyong excerpted several pieces of information, and started calculations at the same time as Xu Yun.

five minutes later.

  Xu Yun and Yu Yuanyong raised their heads one after another.

   Lin Zhenhua on the side noticed.

  At this moment, the expressions of both of them are a little dignified, not as happy as expected.

  Then the two looked at each other, only to hear Xu Yun say:

   "Director Yu, how many orders of magnitude has the Raman signal amplified?"

  Yu Yuanyong frowned, and reported a number:

   "Five weights, how about you?"

  Xu Yun raised the counting paper in his hand towards him:

   "It's also five, five characters won't work."

  Yu Yuanyong's brows suddenly became deeper, and he looked at the report again, and said with a puzzled expression:

   "Strange, the center of the charge transfer transition absorption band is around 220nm, and the nearest ultraviolet laser near this absorption band is 244nm, the data must be correct."

   "According to the resonance Raman principle, when the energy of the excitation light source is close to the electronic absorption band, resonance must occur between the electronic state and the vibrational state."

   "The intensity of the Raman signal of the vibration mode related to this resonance conforms to the transition formula, so the magnitude of the four-coordination should be 6 to 7."

  Xu Yun also picked up the report, trembling like a doctor looking at a CT scan, and began to examine it carefully.

   A few minutes passed.

  Xu Yun's expression froze suddenly, and he pointed to a certain column and said to Yu Yuanyong:

   "Director Yu, look here, why is there such a strong Raman peak at the position of 530?"

   After a while.

  Yu Yuanyong and Xu Yun thought of something at the same time, and said in unison:

   "Selective excitation?"

  Selective excitation.

   refers to a situation where the feedback of the statement is lower than expected within a certain range.

   It may be man-made, or it may be spontaneously generated due to lack of energy during the reaction.

   It's like a gas stove in our life.

  Sometimes you turn on a low heat because this dish must be stewed with low heat.

  You can always turn up the firepower if necessary.

   But sometimes you turn down the heat because the pipe is really flat.

  Xu Yun and the others encountered the latter situation, or an enhanced version of the latter:

  The gas pipe in your house is out of gas, and at the same time, the gas company also sends the gas that should have been sent to your house to your neighbor's house, causing an overflow.

  Looking at the frowning two people who looked like writers who had subscribed in the background, Lin Zhenhua couldn't help saying:

   "Xiao Yu, Xiao Xu, my major is in industry, and I don't quite understand the concept of selective excitation. Anyway, can we solve it?"

  Xu Yun pondered for a moment when he heard the words, and said:

   "I'm afraid it's very difficult. We use scandium, which is the least difficult, and the ion beam chooses iron, which has non-selective oxidation properties."

   “Then there is selective excitation, probably because of some impulsive features in the interaction phase.”

   "For example, iron ions and chemical intermediates produced some band feedback, which delayed the reaction that should have occurred in the third minute to the fifth minute."

   "Of course, this is just a metaphor. In short, it is difficult to solve this kind of problem in a short time."

   "Our only choice at present is to bite the bullet and adopt this method for production. After all, although the wave band is different from the straight line, there are still some products."

   "Just in this way, our production cost and efficiency will be affected."

  Lin Zhenhua frowned:

"I see."

   Then Xu Yun pondered for a moment, and was about to say something nice to comfort Lin Zhenhua.

   As a result, the words did not come out.

  Old Su on the side suddenly tugged his sleeve lightly.

  Xu Yun stopped talking and turned his head.

  I found that Old Su gave himself a wink of 'talk to the side'.

  Xu Yun thought for a while, pretended to be very casual and patted Lao Su on the shoulder, pointed to the water dispenser not far away and said:

   "Xiao Su, come with me to pour a few glasses of water for everyone. After doing this experiment for so long, anyone who doesn't drink water will have to do it."

  Old Su immediately understood:

   "Okay, senior."

   After walking to the water dispenser.

  Xu Yun glanced around, lowered his voice and asked Old Su:

"What's wrong?"

  Old Su first put a disposable cup into the water outlet, pressed the switch, and said to Xu Yun:

   "Xiao Xu, I don't know much about the specific concepts you are talking about, but the so-called chemical intermediates reminded me of one thing. I don't know if it inspires you."

   "So let me just talk, and you can listen to it as you like."

   "It would be best if you can help. If you make a mistake, just ignore it."

  Xu Yun put a plastic cup filled with water aside, and replied:

   "Mr. Su, but it doesn't matter."

  Old Su nodded, pondered for a moment, and said:

   "When you were assembling the telescope that day, you mentioned one thing, and the old man has never forgotten it."

   "At that time, your general meaning was that the telescope needed a paraboloid as an intermediary carrier to reflect the object image, but the industrial level of the Song Dynasty was limited, and the spherical mirror that met your requirements could not be processed."

   "So then you took a different approach and used rotating mercury to achieve the parabolic effect."

   "In my mind, since the so-called chemical intermediate is also intended to play a relay effect, maybe its principle has no intersection with the mercury paraboloid, but the two may have some similarities in nature."

   "Since this is the case, the old man wants to ask a question."

   "Is it possible to bypass the current situation and try to use a liquid to make this intermediate, and use the special properties of the liquid to avoid the occurrence of selective excitation?"

   Heard this.

  Xu Yun was taken aback for a moment.

   Immediately, the pupils shrank suddenly!

   What Lao Su said is a classic operation he compared in the copy of the Northern Song Dynasty:

  At that time, there was no knife-edge instrument and interferometer in the copy, so Xu Yun could not grind out an accurate spherical lens.

  So he cleverly used rotating mercury to realize the paraboloid, and achieved the same effect through the RC-like structure.

   Although this operation has no intersection with catechol.

   But as Lao Su said.

  The two are actually somewhat similar in nature.

  One reflects light, the other feeds back the band.

   all play the effect of a relay.

  So if you can expand through this idea, replace catechol with some other special liquids.

  At the same time, through the centrifugal force of the liquid, the wave band where the solid matter exists is fed back to the balance.

   seems

   Really feasible?

   This chapter came out with the overnight **** code. At 6:30, my uncle came to take my place and go to bed. I'm not sure if there will be tonight.

   If there is an update tonight, this chapter will be counted as an update for returning the lord, if not it will be counted as today's normal update, depending on when I wake up.

  (end of this chapter)

Chapter end