What is Catalytic Hydrogenation
Catalytic Hydrogenation (Catalytic Hydrogenation) is a reaction in which, in the presence of a metal catalyst, the H-H bond in the hydrogen is cleaved and the active hydrogen atoms are adsorbed on the surface of the metal catalyst. Unsaturated reactants (e.g. olefins) are adsorbed on the catalyst vacancies through π-bonds, and then the active hydrogen atoms gradually migrate to the reactant molecules, where an addition reaction occurs, resulting in saturated products (e.g. alkanes). Catalytic hydrogenation process is a crucial technology in petroleum refining and chemical production, which is mainly used to remove sulfur, nitrogen, oxygen-containing compounds and metal impurities, to improve the storage performance and corrosiveness and combustibility of oils, and to realize the conversion of heavy oils to light oils, and can be used for a variety of oil products. The development of this process technology stems from the growth of the petrochemical industry’s demand for high-efficiency, high-purity, clean fuels, but it is not only used in the petroleum industry, and in recent years it has also been widely used in a number of fields such as food, medicine, new energy, environmental protection and so on, for example, carbon dioxide hydrogenation to make the new and clean aviation fuels.

Filtration Recovery Catalyst Difficulties
Precious metals (palladium, platinum, ruthenium, rhodium, cesium, etc.) are often used as catalysts for hydrogenation reactions. The global refining industry produces 120,000 tons of waste catalysts per year, of which China accounts for about 50,000 tons/year [2]. Due to the high cost of catalyst itself, in order to improve the production efficiency often in the reaction will use high metal loading catalyst or increase the amount of catalyst, resulting in a large number of discarded catalysts become hazardous waste pollutants, the subsequent treatment process is complex, so a large number of catalysts filtration recycling has become a petrochemical as well as new energy materials production in an urgent solution to the problem, the specific difficulties are as follows: – High-speed stirring in the reaction makes the The catalyst is abraded to ultra-fine particles by high-speed stirring in the reaction, which is difficult to be recovered 100% by traditional filtration methods; – Catalyst powder (e.g. Raney nickel, palladium carbon, etc.) is prone to spontaneous combustion when leaked in the air; – Filter cartridge clogging needs to be replaced regularly, which affects the continuous production due to frequent stoppages of production; – It is difficult to adapt to the specific extreme working conditions of the filter bags and ceramic membranes.

Shinkai Filtration’s catalyst recovery technology
Nanjing Shinkai Filtration has designed and manufactured a new type of catalyst filtration and separation system by learning from the advanced separation and filtration experience of excellent petrochemical companies at home and abroad, and through the independent production of metal filter elements. The catalyst is separated from the reaction solution in time by filtration from the outside to the inside or from the inside to the outside, which ensures that the catalyst particles are completely intercepted, improves the purity of the product liquid, reduces the amount of catalyst loss, saves the production cost, and improves the economic benefits, and the system has the following advantages:

• 100% catalyst interception and recovery, the pore size and distribution of the filtration media are strictly controlled, and the absolute filtration precision can be adjusted; – Totally enclosed space design and automated control, reducing the risk of workers’ operation and environmental protection pressure;
• The metal membrane is easy to regenerate through backblowing/backwashing, and the element is not easy to scrape and wear, with a life span of up to ten years;
• Impact-resistant, high alternating load metal membrane with stable shape;
• A wide range of filtration media to suit acid, alkali, high temperature and high pressure applications, including 304L, 316L, monel, inconel, hastelloy, nickel metal and titanium and its alloys;
• Batch processing and continuous filtration and separation of catalysts are possible, realizing a variety of processes in chemical production;
• The catalyst can be set repeatedly, avoiding deactivation during catalyst cleaning;
• Compliance with PED, ASME, IBR, EAC and other standards.

For example, our Raney nickel catalyst filter adopts the principle of staggered flow filtration, which can completely separate and filter particles of 0.45 ~ 100μm, and the solid content of the concentrate can reach 20%, and the catalyst recovery rate reaches 100%. The catalyst filters produced by Shinkai have been used in hundreds of sets in domestic API, dye intermediates, petroleum hydrogenation, pesticides, spices, hydrogen peroxide, caprolactam, etc., which have perfectly solved the problem of liquid-solid separation, and created great economic benefits for customers.