Abstract: Apparatus and a method are disclosed for transferring acid catalyst from a transport vehicle where liquid acid is carried under a relatively low vapor pressure level to a process vessel in an alkylation process where liquid acid is contained at a higher pressure level, while minimizing the loss of acid vapor to the environment. The acid transfer is accomplished without venting the process vessel by employing a relatively small volume pressure lock chamber between the transport vessel and the storage vessel. In a preferred embodiment the small volume pressure lock chamber also serves as a storage vessel for make-up acid which is added to the alkylation process as required.

Abstract: The molecular weight of solid polymers, particularly polyolefins, is modified by addition of organic peroxides (or other free radical generators), which is admixed in a first reaction zone. The polymer is then melted followed by addition of additives such as antioxidants and light stabilizers, which are admixed in a second reaction zone where intense and rapid mixing occurs, such as within the barrel of an extruder. The separate admixture of primary and secondary additives provides improved color and odor characteristics for the polymer compared to concurrent admixture of all the additives.

Abstract: In a continuous adsorption process using dual towers for separation of a multi-component feed with one tower active and the other on regeneration, automatic switching of the tower feed based on loading of a hydrogen fluoride (HF) component in the active tower is achieved by inferring HF loading based on concentration measurement of acid soluble oil (ASO). An optimum switching point, which switches tower feed near full HF capacity of the active tower but before HF breakthrough occurs, is based on calculating a second derivative for a concentration vs. time curve of ASO in the active bed effluent.

Abstract: In an endothermic steam active catalytic process employing a fixed catalyst bed in a fuel fired reactor for the dehydrogenation of alkanes to alkenes, wherein a reaction temperature above about 500.degree. C. (932.degree. F.) is maintained for commercially feasible conversions, and wherein catalyst activity declines during a production period, apparatus for control of a process temperature so as to compensate for catalyst activity decline includes a temperature sensor mounted in the reaction effluent stream in combination with a temperature controller which automatically adjusts the quantity of fuel supplied to the fired reactor.

Abstract: The presence of an undesirable quantity of noncondensible gases in a refrigeration unit is inferred as a function of both the vapor pressure and temperature at a selected point in the refrigeration unit where the noncondensible gases tend to gather. Purging of these noncondensible gases, which contaminate the refrigerant, is responsive to a comparison in a programmable controller of the actual vapor pressure measured at the selected point, and the known pressure of uncontaminated refrigerant at the temperature existing at the selected point. On detecting a difference between these pressures that is greater than a desired value, the controller calculates a control output signal needed to purge a volume of contaminated vapor from the unit that is effective for reducing the difference between the measured pressure of contaminated refrigerant and the known pressure of uncontaminated refrigerant to a desired value.

Abstract: In a fractional distillation process which performs a binary or limited multicomponent separation, and in which it is desired to maintain composition set points for dual product streams, a computer is programmed for applying model based control. Multivariable, noninteracting control of the distillation process is achieved by utilizing a nonlinear model, which calculates process vapor and distillate flow rates required to maintain product set points. The model, which applies tray-to-tray calculation essentially derived from a McCabe-Thiele analysis, is periodically updated by adjusting tray efficiency based on steady state composition measurements to keep the model in pace with changing process conditions.

Abstract: Catalyst life in desulfurization of distillate hydrocarbon streams is predicted with the aid of a computer simulation which embodies an analytical kinetic model of a hydrodesulfurization reaction and a semi-empirical model for catalyst deactivation. The simulation specifies the decline of catalyst activity with time and a current reaction temperature required to maintain the initial catalyst activity. The useful life of the catalyst is considered to be the time required for catalyst activity in the simulated reaction to decline sufficiently from its initial level so that a predefined maximum reaction temperature is reached while maintaining a desired level of sulfur in the desulfurized product. The computer time needed to simulate the reaction is decreased by combining superior features of LOTUS 1-2-3 and FORTRAN language, such that input/output and graphic operations are implemented with LOTUS 1-2-3 and numerical calculations are executed in FORTRAN.

Abstract: In an on-line annealing process for rigid laminated sheets of reinforced thermoplastic material wherein an annealing chamber is maintained at a desired temperature by introducing heated air to impinge on a deflection plate within the annealing chamber, annealing of the thermoplastic sheets is improved by introducing heated air through a pair of elongated perforated tubes within the annealing chamber so that heated air is diffused so as to flow evenly across both sides of the rigid thermoplastic sheet as the sheet passes through the annealing chamber.

Abstract: Sludge is removed from a reboiler while the reboiler is supplying heat to a fractionator, by using sludge removal apparatus added to the reboiler. The reboiler to which the sludge removal apparatus is added comprises an evaporative type shell and tube heat exchanger in which sludge can accumulate as a residue from evaporated liquid, and further in which unevaporated liquid is withdrawn from the reboiler as a product. Sludge removal is accomplished by drawing a relatively small liquid flush stream from the reboiler liquid product stream, pressuring the flush stream through a pump, and then recycling the flush stream to a sparger appropriately disposed in the heat exchanger shell. Sludge dislodged by the sparger is removed along with the reboiler liquid product in a flow path along the bottom surface of the shell through cut-outs provided in the lower edge of the weir and baffle plates in the reboiler which without the cut-outs would block the flow path for the sludge.

Abstract: The alcohol, ether and hydrocarbon components of the reaction effluent from various etherifications of C.sub.4 or C.sub.5 isoolefins with an alcohol such as methanol or ethanol which produce MTBE, ETBE, TAME, or TAEE are separated using identical process equipment. The components are recovered by first removing a portion of the alcohol in a first water extraction step, then fractionating the ether, followed by the removal of additional alcohol in a second water extraction step and then fractionating the alcohol. Hydrocarbons are recovered from a extract stream of the second water extraction step.

Abstract: A crystal, which is mounted in a rotatable support for use in tuning the wavelength of an optical parametric oscillator, is maintained at a desired temperature by positioning a heating sleeve to thermally coupled to the crystal and its support in such a way that the crystal is still free to rotate. The heating sleeve has an embedded heating element for connecting to an electronic controller whose dynamic output response matches the dynamic temperature characteristics of the combination of components including the crystal, it rotatable holder and the heating sleeve, so as to quickly stabilize changes in the crystal temperature with a minimum amount of overshoot.

Abstract: In a steam generator for recovering heat in a hot fluidized bed of solid particles, wherein coils of the steam generator make a 180.degree. U-bend, the U-bend portion of the coils are protected from overheating by installing an open top insulating box around the U-bend portion of the coil. In use solid particles from the circulating fluidized bed accumulate in the insulating box thus providing a non-moving layer of solid particles surrounding the U-bend which thermally insulates the U-bend portion of the coil from the higher temperature encountered in the moving fluidized bed.

Abstract: In a steam generator for recovering heat in a hot fluidized bed of solid particles, wherein generally horizontally oriented coils of the steam generator make a 180.degree. U-bend, the U-bend portion of the coils are protected from overheating by installing an open top insulating box around the U-bend portion of the coil. In use solid particles from the circulating fluidized bed accumulate in the insulating box thus providing a non-moving layer of solid particles surrounding the U-bend which thermally insulates the U-bend portion of the coil from the higher temperature encountered in the moving fluidized bed.

Abstract: A charge dissipating article having a poly(arylene sulfide) polymer surface with a semiconductive layer for static charge dissipation and/or induction shielding made by forming a laminate of a poly(arylene sulfide) substrate against a copper foil sheet at a temperature above the melting point of the PAS substrate, wherein the copper foil sheet has been treated with a silane selected from a specific group. When the laminate is cooled and the copper foil peeled away, a poly(arylene sulfide) substrate having a semiconductive surface coating is obtained.

Abstract: An analyzer system for improving quality of a reaction product, wherein a liquid sample must be maintained at an elevated temperature to prevent precipitation of titratable species, comprises a heated sample and dilution section, an autotitrator and a programmable controller. In operation a liquid sample to be analyzed is withdrawn from a reactor and maintained at reactor temperature while being diluted. The diluted sample is then cooled and passed to an autotitrator for analysis. The analyzer system includes a programmable controller for automatic unattended dilution of successive samples.

Abstract: In a fractional distillation process which performs a binary or limited multicomponent separation, and in which it is desired to maintain composition set points for dual product streams, a computer is programmed for applying model based control. Multivariable, noninteracting control of the distillation process is achieved by utilizing a nonlinear model, which calculates process vapor and distillate flow rates required to maintain product set points. The model, which applies tray-to-tray calculation essentially derived from a McCabe-Thiele analysis, is periodically updated by adjusting tray efficiency based on steady state composition measurements to keep the model in pace with changing process conditions.

Abstract: Preparing an arylene sulfide polymer surface for improved bonding to another surface includes molding the initially smooth polymer surface to fit the contours of a metallic foil having a high topographical surface configuration so as to form a laminate; etching away the metallic foil from the laminate, and thereby imparting the desired high topographical configuration of the metallic foil onto the polymer surface, so as to improve adhesive bonding characteristics of the polymer surface.

Abstract: In a steam active catalytic process employing a fixed catalyst bed for the dehydrogenation of alkanes to alkenes wherein reaction temperatures above about 500.degree. C. (932.degree. F.) must be maintained for commercially feasible conversions, the decline in catalyst activity druing a production period is slowed by maintaining a substantially constant temperature for the reaction effluent while allowing the average temperature of the fixed catalyst bed to rise during a production period.

Abstract: Purification of crude sulfolane to remove color imparting and turbidity imparting impurities therefrom is achieved by a two-pass distillation process wherein purified sulfolane is withdrawn from the bottom of a column in the second distillation pass.

Abstract: An analyzer system for improving quality of a reaction product, wherein a liquid sample must be maintained at an elevated temperature to prevent precipitation of titratable species, comprises a heated sample and dilution section, an autotitrator and a programmable controller. In operation a liquid sample to be analyzed is withdrawn from a reactor and maintained at reactor temperature while being diluted. The diluted sample is then cooled and passed to an autotitrator for analysis. The analyzer system includes a programmable controller for automatic unattended dilution of successive samples.