摘要:
An olefin polymerization process comprises gas-phase polymerization of at least one olefin monomer in more than one polymerization zones in one or more polymerization reactors using a high activity catalyst injected in the front end of the reactor to give solid polymer particles. According to the process of the invention, different hydrogen to olefin ratios are applied to the reactor leading to the production of very different molecular weights and therefore broadening the molecular weight distribution of the polymer produced.
摘要:
A method for providing improved estimates of properties of a chemical manufacturing process is disclosed. The method regesses process variables with scores or other gains obtained from the mathematical transformation of data obtained from an on-line analyzer. Chemical manufacturing processes using the method also are disclosed.
摘要:
This invention involves a process for achieving more energetic fuels by ug high density fullerenes and fullerene derivatives, mixed with liquid hydrocarbon or hydrocarbon derivative fuels. The advantages of the these materials are that they constitute a form of high density carbon which will evaporate or sublime quite easily by comparison to particles of carbon. The fullerenes, or derivatives of fullerenes, exist as molecules which are relatively volatile. These materials are generally solids and therefore easily compounded into hydrocarbon fuels slurries. The derivatives can be tailored for high solubility in hydrocarbon solvents. In addition, the fullerenes can be modified easily to adjust the oxidization susceptibility so that the residence time in the combustion zone can be shortened even further.
摘要:
A solid propellant composition comprising an organic polymer fuel binder, an inorganic perchlorate oxidizer salt, and 1,1"-carbonyl-bis-ferrocene which functions as a stable solid combustion modifier.
摘要:
A method for providing improved estimates of properties of a chemical manufacturing process is disclosed. The method employs a process model that includes, or is modified by, scores or other gains obtained from the mathematical transformation of data obtained from an on-line analyzer. Chemical manufacturing processes using the method also are disclosed.
摘要:
A storage stable polyester polyol mixture is prepared by digesting polyalkylene terephthalate, particularly polyethylene terephthalate, with a digesting medium comprising a polycarboxylic acid component-containing polyol, wherein the polycarboxylic acid component has ring units with two ##STR1## groups on adjacent or alternate ring positions, the ring unit content of the polycarboxylic acid component being sufficient for improved storage stability of the digestion product. The polyester polyol mixture is useful in the preparation of cellular foam materials, particularly polyisocyanurate and polyurethane foams.
摘要:
A method for improving the combustion efficiency, i.e. increasing the burning rate, of propellant, flare, and other pyrotechnic compositions is disclosed which comprises using at least some ammonium perchlorate oxidizer coated with aluminum metal in place of a mere mixture of aluminum and ammonium perchlorate. The resultant compositions have increased burning rate in comparison to mere mixtures of ammonium perchlorate and aluminum.
摘要:
An olefin polymerization process comprises gas-phase polymerization of at least one olefin monomer in more than one polymerization zones in one or more polymerization reactors using a high activity catalyst injected in the front end of the reactor to give solid polymer particles. According to the process of the invention, different hydrogen to olefin ratios are controlled and applied to the reactor leading to the production of very different molecular weights and therefore broadening the molecular weight distribution of the polymer produced.
摘要:
The application discloses a system for controlling a chemical manufacturing process having at least one piece of process limiting equipment in addition to a reactor. The system employs one or more multivariable predictive optimizer controllers for optimizing control of the chemical reactor and production limiting equipment located upstream or downstream of the reactor, to provide integrated process control of the reactor and the production limiting equipment.