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I. Industries where copper-based catalysts are mainly used Copper-based catalysts are widely applied in the hydrogenation of CO and CO2 to produce methane, selective hydrogenation in low-temperature shift reactions, as well as in various industrial reactions such as oxidation and dehydrogenation. 1. Dehydrogenation mechanism of Cu-based catalysts (1) The dehydrogenation reaction mechanism of catalysts can vary depending on the type of reactants and the catalyst used, and sometimes it changes as well depending on the reaction conditions. There are two types of catalytic dehydrogenation mechanisms for Cu-based catalysts: 1. The radical mechanism, in which hydrogen atoms are removed from the reactants through homolytic cleavage. The catalyst is required to possess unpaired active centers, as well as strong bonding capabilities and sufficient exposure in order to come into contact with and interact with the hydrogen atoms on C-H bonds. Dehydrogenation catalysts that meet the requirements of this mechanism can be metals such as Ni and Cu, or metal oxides, sulfides, etc. (2) In the ionic mechanism, the reactant molecule is first acted upon by the metal ion M on the catalyst, resulting in the removal of H (C-H bond cleavage), and then another H is removed to form an unsaturated bond. The reacting molecules need to be easily polarized in order to produce C8+H8; the catalyst also requires metal ions with strong polarization capabilities to remove H+, along with O2- ions carrying a negative charge to accept the H+. Therefore, this type of mechanism is similar to acid-base catalysis. 2. Applications in methanol dehydration reactions: In recent years, with the continuous development of the methanol industry, the development of downstream products from methanol and its conversion into other organic chemical products has attracted the attention of researchers around the world. Methanol dehydration can produce methyl alcohol and methyl formate, or it can also break down into carbon monoxide and hydrogen. II. Industries where nickel-based catalysts are primarily used III. Recovery and removal of wastewater containing heavy metal ions. In many industrial processes, such as those involving copper- and nickel-based catalysts, large amounts of wastewater containing copper and nickel ions are generated. If such wastewater is discharged into water bodies, it can severely affect water quality and cause environmental pollution; when the copper concentration in water reaches 0.01 mg/L, it has a significant inhibitory effect on the natural purification capacity of the water ； Above 3.0 mg/L, an unpleasant odor will be produced ； If it exceeds 15 mg/L, it cannot be drunk. Heavy metal elements exist in water in combined or ionic forms and are difficult to biodegrade. Common treatment methods for such industrial wastewater include chemical precipitation, electrolysis, chemical displacement, adsorption, ion exchange, and biological treatment techniques. However, when it comes to solvent purification, ion exchange is the most suitable method among these options; it allows for the removal of excess copper and nickel from the solution while ensuring the purity of the product, without generating sludge containing heavy metals or causing solvent loss. The ion exchange method is highly effective in removing copper, especially from wastewater with low concentrations. The ion chelation method involves directly adding heavy metal chelators to wastewater, so that these chelators capture metal ions and thereby form chelates. The chelates formed by this method are highly stable, the sludge settles rapidly, and the capture efficiency is not affected by the coexistence of alkali metals and alkaline earth metals, nor by changes in pH value. When treating wastewater containing complexed copper using ion exchange resins, Cu-EDTA and free EDTA can be concentrated and recovered, resulting in a copper ion concentration in the purified water of less than 0.1 mg/L. The ion exchange process is simple, the equipment required is not complex, it offers excellent results for the selective extraction of metal ions, and the resin can be regenerated. Therefore, when removing low-concentration ions from wastewater, the ion exchange method is the most effective and cost-saving approach. IV. Examples of the application of Tulsimer®CH-90Na resin. Some examples of the use of ion exchange resins to remove heavy metal ions such as copper and nickel are as follows: 1. A chemical enterprise in Chongqing (in the purification of 1,4-butyne diol); 2. Another chemical enterprise in Henan (also in the purification of 1,4-butyne diol). Below are the comparison test results between domestic resins and CH-90Na, along with a summary of those results. The figure above shows the adsorption isotherms of Resin 1# and Resin 2# measured at room temperature; Resin 2# was measured multiple times because its performance was significantly better than that of the domestic Resin 1# we had anticipated. The results of multiple measurements are consistent (the three non-black curves); the behavior of resin 2# fully conforms to the Langmuir adsorption isotherm equation used to describe chemisorption with saturation, whereas resin 1# shows a certain depression in the low-concentration region. The results of the adsorption isotherms show that, at the same equilibrium concentration (concentration of liquid copper ions), the adsorption capacity of resin 2# is much higher than that of resin 1#. For example, at 20 mg/L, the adsorption capacity of resin 1# is 1.5 mg/g, whereas that of resin 2# is 6 mg/g, which is four times that of resin 1#. The depressed adsorption isotherm of resin 1# also indicates that it is not suitable for the treatment of low-concentration copper ions. To simulate the actual dynamic adsorption process, we determined penetration curves. The experiment was conducted at room temperature, with the flow rate controlled at 2 BV/h, which is similar to the operating conditions in actual production. The experimental results also demonstrated the superiority of imported resin 2#. Using the absence of copper ions as the evaluation criterion, resin 1# showed penetration after 5 BV, while the penetration volume of resin 2# reached 40 BV. Therefore, considering operational cycles and waste liquid among other factors, choosing resin 2# as the adsorbent offers advantages such as a longer operating cycle, less waste liquid, and a higher concentration.