45results about How to "Synthetic process conditions are mild" patented technology

The invention discloses a Pd nanocomposite catalyst for catalyzing the decomposition of formic acid to produce hydrogen and a preparation method thereof, belonging to the field of hydrogen storage materials. The catalyst is prepared by loading ultra-small Pd nano-clusters on the surface of a composite support composed of an inorganic support and amino-modified graphene oxide. The preparation method comprises: compounding graphene oxide and inorganic nanomaterials under the action of chemical bonds by stirring for a long time, and then modifying the outer surface of graphene oxide with amino groups, then adding a Pd salt solution, and reducing the graphene oxide by sodium borohydride. The dispersed Pd nanoclusters are stabilized on the surface of the carrier, and the obtained Pd nanocomposite catalyst can be used to efficiently catalyze the decomposition of formic acid to produce hydrogen. The synthesis process of the present invention has mild conditions, and has very high activity in catalyzing the decomposition of formic acid to produce hydrogen under mild conditions. After the catalysis is completed, it is easy to separate from the system and can be recycled. And fuel cells and other fields have broad application prospects.

The invention discloses a method for preparing a concrete water reducer with styrene sulfonate as monomers, and belongs to the field of water reducers. The method includes the steps that firstly, styrene sulfonate and unsaturated carboxylic acid monomers are subjected to free radical copolymerization to obtain a polycarboxylic acid-styrene sulfonate main chain, and then benzene sulfonate on the main chain is modified into phenylsulfonyl halide groups; then, an oxidation-reduction initiating system is formed by high-valence cerate and alcohol to initiate polymerization of unsaturated cationic quaternary ammonium monomers to obtain a hydroxyl-terminated cationic long chain; then, the polycarboxylic acid main chain containing the phenylsulfonyl halide groups, the hydroxyl-terminated cationic long chain and a polyethylene glycol compound are subjected to sulfonylation to obtain the concrete water reducer. According to the method, based on the molecular structure design principle, by modifying styrene sulfonate into phenylsulfonyl halide and carrying out sulfonylation on grafted cationic side chains and polyethylene glycol side chains, the novel concrete water reducer containing a double-side-chain structure is successfully synthesized; the reaction process is mild, easy to control, capable of saving energy and efficient, and the concrete water reducer shows multiple excellent effects of water reduction for slump loss resistance, clay resistance and the like.

The invention provides a method for preparing a nitrogen-doped carbon material catalyst, comprising the following steps: A, adding a nitrogen-containing compound and a carbon material into ethanol respectively, and stirring for 5-20 hours at a temperature range of 0-70°C; B. 1. Separating the liquid obtained in step A into solid-liquid, and drying the separated solid; C. Grinding the dried solid obtained in step B, and calcining it under an inert atmosphere to obtain a nitrogen-doped carbon material catalyst. The catalyst described in the invention can efficiently and selectively catalyze the hydrogenation of aromatic compounds under mild conditions, reduce the amount of metal used, reduce the cost of the catalyst, improve catalyst activity, stability and hydrogenation selectivity, and also have good electrocatalytic performance .

The invention discloses a making method of 2, 3-dihydroxy butyl inner hemiacetal derivative with optical activity as chiral intermediate, which comprises the following steps: preparing tartrate ester (3); making tartrate ester (4) protected by alkyl or benzyl or silicon as R1; making 1, 4-butanediol (5); making 2,3-dihydroxy dihydroxy butyl inner hemiacetal derivative (1) under mild synthesizing technique and easy operation with high receiving rate. The invention improves the optical purity of the product, which is a convenient, economic and high-effective product.

The invention relates to a method for preparing pH-responsive comb-structure polycarboxylic acid through terminal group functionalization. According to the method, with a pH-responsive monomer, unsaturated halogenated hydrocarbon, a small carboxylic acid momonomer and the like as raw materials, a polycarboxylate material is prepared through self-polymerization first, then substitution and then copolymerization; namely, with the pH-responsive monomer as a reactant, a terminal group-functionalized pH-responsive polymer chain is produced through the self-polymerization under the actions of an initiator and a terminal group functionalizing agent, then a substitution reaction is performed on the terminal group-functionalized pH-responsive polymer chain and the unsaturated halogenated hydrocarbon to obtain a pH-responsive macromonomer, and finally a copolymerization reaction is performed on the pH-responsive macromonomer and the small carboxylic acid momonomer under the action of the initiator to obtain a comb-structure polymer which uses polycarboxylic acid as a main chain and has a side chain with a pH-responsive function. By the method, the process is high-efficiency and energy-saving, the conversion rate of a product is high, the functional modification of the polycarboxylic acid is successfully achieved through introduction of the pH-responsive polymer side chain by a terminal group functionalization method, an excellent characteristic of inhibiting shrinkage of cement mortar is shown, and the market competitiveness and the application prospect are very good.