67results about How to "Conducive to follow-up reactions" patented technology

The invention discloses a preparation method for cadmium telluride. The preparation method sequentially comprises the following steps: qualified tellurium powder and cadmium powder are taken according to the molar ratio of 1:1 and then subjected to homogeneous mixing, the mixed raw materials subjected to homogenizing are loaded into a graphite boat, and the graphite boat is placed into a synthesis furnace for first synthesis; the material obtained after first synthesis is taken out of the graphite boat and crushed; the crushed material is loaded into the graphite boat, and the graphite boat is placed into the synthesis furnace for second synthesis; screening and ball milling are performed, wherein in the processes of the first synthesis and the second synthesis, multistage temperature rising and temperature dropping are performed under the protection of nitrogen and hydrogen. According to the invention, homogeneous treatment is performed on the tellurium powder and cadmium powder firstly so as to enable the two raw materials to be mixed fully and uniformly, meanwhile, the defect that the cadmium powder is easy to oxidize is overcome, the two raw materials can be synthesized preliminarily under relatively low temperature, purity of a synthesized product is improved, and the utilization ratios of raw materials are increased; synthesis is performed for two times, so that the raw materials react fully, thereby improving the purity and yield of the product finally.

The invention discloses a biochemical landfill leachate treatment process, which comprises: adjusting the pH value of landfill leachate with an ammonia nitrogen concentration of more than 2000 mg / L and B / C of less than 0.2 to 8-9, and filtering; precipitating the filtered landfill leachate in a coagulation pool; carrying out electrolysis treatment on the effluent of the coagulation pool for 20-30min in an electrolysis tank with a voltage of 3-5 V by using a titanium alloy electrode and a composite electrolyte, wherein the composite electrolyte comprises sodium hydroxide and hydrochloric acidfor adjusting the pH value of the effluent of the coagulation pool to 6-9, sodium chloride for adjusting the TDS value of the effluent of the coagulation pool to more than or equal to 6000 mg / L, and sodium hypochlorite for adjusting the redox potential of the effluent of the coagulation pool to more than -300 mV; and sequentially carrying out catalytic ozone oxidation treatment and biochemical treatment on the effluent of the electrolysis tank. According to the present invention, with the process, by adjusting the TDS value and the redox potential, the direct oxidation effect and the indirectoxidation effect in the electrolysis reaction are optimally balanced so as to obtain the optimal ammonia nitrogen and COD removal effect at low energy consumption.

The invention relates to the technical field of preparation of new fluorine-containing materials, particularly to an environmentally friendly preparation method of fluorine-containing acrylate. The environmentally friendly preparation method comprises: carrying out a reaction on short-chain perfluoroiodoalkane and ethylene, separating, and purifying to obtain perfluoroalkylethyl iodide; carrying out hydrolysis on the perfluoroalkylethyl iodide, separating, and purifying to obtain perfluoroalkylethanol; and carrying out a reaction on the perfluoroalkylethanol and acrylic acid, separating, and purifying to obtain the product. According to the present invention, the perfluorooctyl-free product is synthesized, the potential risk of PFOA production cannot exist, and the obtained product is theenvironmentally friendly product, and meets the national industrial policy; the preparation method is simple, and is suitable for industrial production; and the reaction conversion rate is high, and the purity of the intermediate product is high, such that the subsequent reaction is easily performed, the yield is easily increased, and the cost is reduced.