| LANZHOU INSTITUTE OF CHEMICAL PHYSICS, CHINESE ACADEMY OF SCIENCES Patent applications |
| Patent application number | Title | Published |
| 20110313202 | METHOD FOR PREPARING POLYOXYMETHYLENE DIMETHYL ETHERS BY ACETALATION REACTION OF FORMALDEHYDE WITH METHANOL - It is disclosed a method for preparing polyoxymethylene dimethyl ethers by continuous polymerization and acetalation reactions. The method may include two steps: performing a polymerization reaction of an aqueous formaldehyde solution under catalysis of an ionic liquid IL I to obtain a mixed aqueous solution of trioxymethylene and formaldehyde; and an acetalation reaction of the mixed aqueous solution of trioxymethylene and formaldehyde with methanol is performed under catalysis of an ionic liquid IL II to prepare polyoxymethylene dimethyl ethers. The method may use an aqueous formaldehyde solution as a starting material to prepare polyoxymethylene dimethyl ethers by continuous polymerization and acetalation reactions, achieving a high use ratio of formaldehyde. A film evaporator is used in the invention, realizing a rapid separation and recycling of the light components, with a high separation efficiency. The separation of the catalyst is simple, thereby realizing recycling of the catalyst. | 12-22-2011 |
| 20110288343 | METHOD FOR SYNTHESIZING POLYOXYMETHYLENE DIMETHYL ETHERS CATALYZED BY AN IONIC LIQUID - It is related to a method for preparing polyoxymethylene dimethyl ethers by a continuous acetalation reaction of trioxymethylene and methanol or methylal catalyzed by an ionic liquid. The processing apparatus used in the method includes a reaction zone, a separation zone, a catalyst regeneration zone and a product dehydration zone. A manner of circulating tubular reaction is used, resulting in a high external heat exchange efficiency, a simple structure of design and a low investment. A film evaporator is used, realizing a rapid separation and recycling of the light component, with a high separation efficiency. The separation of the catalyst solution from the crude product is simple, thereby realizing the regeneration and recycling of the catalyst. | 11-24-2011 |
| 20110021810 | METHOD FOR PREPARING ISOCYANATES BY LIQUID-PHASE THERMAL CRACKING - The present invention discloses a method for preparing isocyanates by liquid-phase catalytic thermal cracking. In this method, in a reaction-rectification thermal cracking reactor, using a catalyst composition comprising a superfine powder metal oxide catalyst and an ionic liquid, an alkyl or aryl dialkylurethane, or multialkylurethane being a reactant is liquid-phase thermal cracked for a reaction time of 0.5-3 h under a reaction temperature of 160-220° C. and an absolute pressure of 1000-8000 Pa so as to prepare the corresponding isocyanate. The invention has the characteristics of low thermal cracking temperature, high yield of target products, relatively simple reaction apparatus and good universality for substrates (the yields of HDI, MDI, TDI, HMDI, NDI and IPDI or the like are all >85%) and the like. | 01-27-2011 |
| 20100056830 | METHOD FOR SYNTHESIZING POLYOXYMETHYLENE DIMETHYL ETHERS BY IONIC LIQUID CATALYSIS - The present invention discloses a method for synthesizing polyoxymethylene dimethyl ethers by ionic liquid catalysis. The method comprises synthesizing polyoxymethylene dimethyl ethers by using a functional acidic ionic liquid as catalyst and using methylal and trioxymethylene as reactant under a relative mild reaction condition. The invention has advantages of high catalyst activity and reaction conversion, simple reaction process, high operationability and controllability, as well as good product distribution and high raw material utilization ratio. | 03-04-2010 |
| 20090036715 | METHOD FOR PREPARING POLYMETHOXYMETHYLAL - This invention describes a method for preparing polymethoxymethylal. By this method, polymethoxymethylal is prepared by a catalytic reaction using methanol and trioxymethylene as reactants and using an ionic liquid as catalyst under a relatively moderate reaction condition. The catalyst of this invention has a high catalytic activity and a high conversion; the reaction process is simple, easy to be operated and has a strong controllability; the distribution of the products after reaction is superior and the utilization ratio of the raw materials is high. | 02-05-2009 |
| 20080293954 | Process For Synthesizing Trioxymethylene Using Ionic Liquid - The present invention relates to a process for synthesizing trioxymethylene, wherein an aqueous solution of formaldehyde is used as the reactant; and an acidic ionic liquid in an amount of from 0.01 to 10 wt % is used as a catalyst. | 11-27-2008 |