In a method for oxidizing 1,1-bis-(3,4-dimethylphenyl)-alkane with nitric acid in a pressure vessel to produce 3,3′,4,4′-benzophenone tetracarboxylic acid with concurrent formation of nitric oxide, passing nitric oxide from the pressure vessel into an absorption vessel and reacting nitric oxide in the absorption vessel with molecular oxygen and water to produce an aqueous nitric acid solution prevents discharge of nitric oxide, avoids the risk of oxygen inhibiting the nitric acid oxidation and reduces nitric acid consumption when the nitric acid from the absorption vessel is used for oxidizing the 1,1-bis-(3,4-dimethylphenyl)-alkane.

In a method for oxidizing 1,1-bis-(3,4-dimethylphenyl)-alkane with nitric acid in a pressure vessel to produce 3,3′,4,4′-benzophenone tetracarboxylic acid with concurrent formation of nitric oxide, passing nitric oxide from the pressure vessel into an absorption vessel and reacting nitric oxide in the absorption vessel with molecular oxygen and water to produce an aqueous nitric acid solution prevents discharge of nitric oxide, avoids the risk of oxygen inhibiting the nitric acid oxidation and reduces nitric acid consumption when the nitric acid from the absorption vessel is used for oxidizing the 1,1-bis-(3,4-dimethylphenyl)-alkane.

A valve assembly having a conical valve needle axially displaceable in a bore of a valve body wherein a portion of the larger diameter of the valve needle seats downstream at an annular ring when the valve is closed. There is an open area between one end of the valve body to the annular ring even at closure and nozzles for the input of a liquid. The inner wall of the valve body comprises at least one opening for the entry of a liquid under pressure following output of a slurry or liquid from a tube or pipe. The valve assembly is particularly useful in maintaining a semi-continuous or continuous pressurized flow of biomass from an extruder.

A process for performing a continuous gas/liquid biphasic high-pressure reaction, wherein a gas and a liquid are introduced into a backmixed zone of a reactor and in the backmixed zone the gas is dispersed in the liquid by stirring, injection of gas and/or a liquid jet, a reaction mixture consecutively traverses the backmixed zone and a zone of limited backmixing, and a liquid reaction product is withdrawn at a reaction product outlet of the zone of limited backmixing, wherein the reactor comprises: an interior formed by a cylindrical vertically oriented elongate shell, a bottom and a cap, wherein the interior is divided by means of internals into the backmixed zone, the zone of limited backmixing and a cavity, a first cylindrical internal element which in the interior extends in the longitudinal direction of the reactor and which delimits the zone of limited backmixing from the backmixed zone, backmixing-preventing second internal elements in the form of random packings, structured packings or liquid-permeable trays arranged in the zone of limited backmixing and a third internal element which in the interior extends in the longitudinal direction of the reactor and is open at the bottom, wherein the third internal element forms the cavity in which gas bubbles collect and do not escape upwards, thus preventing the volume of the cavity from being occupied by liquid and reducing the reaction volume. The reaction volume of the reactor used in the process can be reversibly reduced in simple fashion. The invention further relates to a process for adapting the reaction volume of a reactor suitable for performing a gas/liquid biphasic high-pressure reaction having an outlet for a liquid reaction product in which an internal element is arranged so as to form a cavity open at the bottom in which gas bubbles collect and do not escape upwards, thus preventing the volume of the cavity from being occupied by liquid and reducing the reaction volume.

A process for performing a continuous gas/liquid biphasic high-pressure reaction, wherein a gas and a liquid are introduced into a backmixed zone of a reactor and in the backmixed zone the gas is dispersed in the liquid by stirring, injection of gas and/or a liquid jet, a reaction mixture consecutively traverses the backmixed zone and a zone of limited backmixing, and a liquid reaction product is withdrawn at a reaction product outlet of the zone of limited backmixing, wherein the reactor comprises: an interior formed by a cylindrical vertically oriented elongate shell, a bottom and a cap, wherein the interior is divided by means of internals into the backmixed zone, the zone of limited backmixing and a cavity, a first cylindrical internal element which in the interior extends in the longitudinal direction of the reactor and which delimits the zone of limited backmixing from the backmixed zone, backmixing-preventing second internal elements in the form of random packings, structured packings or liquid-permeable trays arranged in the zone of limited backmixing and a third internal element which in the interior extends in the longitudinal direction of the reactor and is open at the bottom, wherein the third internal element forms the cavity in which gas bubbles collect and do not escape upwards, thus preventing the volume of the cavity from being occupied by liquid and reducing the reaction volume. The reaction volume of the reactor used in the process can be reversibly reduced in simple fashion. The invention further relates to a process for adapting the reaction volume of a reactor suitable for performing a gas/liquid biphasic high-pressure reaction having an outlet for a liquid reaction product in which an internal element is arranged so as to form a cavity open at the bottom in which gas bubbles collect and do not escape upwards, thus preventing the volume of the cavity from being occupied by liquid and reducing the reaction volume.

Disclosed are a method and system for propylene polymerization utilizing a loop slurry reactor. The method can include polymerizing propylene in a loop slurry reactor under bulk polymerization conditions to produce polypropylene. The propylene polymerization system can include i) a loop slurry reactor and a heat exchange system that is configured to cool the legs of the loop slurry reactor and/or ii) an inlet manifold that is configured to connect flashline heaters to a separator.

A process for performing a continuous gas/liquid biphasic high-pressure reaction, wherein a gas and a liquid are introduced into a backmixed zone of a reactor and in the backmixed zone the gas is dispersed in the liquid by stirring, injection of gas and/or a liquid jet, a reaction mixture consecutively traverses the backmixed zone and a zone of limited backmixing, and a liquid reaction product is withdrawn at a reaction product outlet of the zone of limited backmixing, wherein the reactor comprises: an interior formed by a cylindrical vertically oriented elongate shell, a bottom and a cap, wherein the interior is divided by means of internals into the backmixed zone, the zone of limited backmixing and a cavity, a first cylindrical internal element which in the interior extends in the longitudinal direction of the reactor and which delimits the zone of limited backmixing from the backmixed zone, backmixing-preventing second internal elements in the form of random packings, structured packings or liquid-permeable trays arranged in the zone of limited backmixing and a third internal element which in the interior extends in the longitudinal direction of the reactor and is open at the bottom, wherein the third internal element forms the cavity in which gas bubbles collect and do not escape upwards, thus preventing the volume of the cavity from being occupied by liquid and reducing the reaction volume. The reaction volume of the reactor used in the process can be reversibly reduced in simple fashion. The invention further relates to a process for adapting the reaction volume of a reactor suitable for performing a gas/liquid biphasic high-pressure reaction having an outlet for a liquid reaction product in which an internal element is arranged so as to form a cavity open at the bottom in which gas bubbles collect and do not escape upwards, thus preventing the volume of the cavity from being occupied by liquid and reducing the reaction volume.

A process for performing a continuous gas/liquid biphasic high-pressure reaction, wherein a gas and a liquid are introduced into a backmixed zone of a reactor and in the backmixed zone the gas is dispersed in the liquid by stirring, injection of gas and/or a liquid jet, a reaction mixture consecutively traverses the backmixed zone and a zone of limited backmixing, and a liquid reaction product is withdrawn at a reaction product outlet of the zone of limited backmixing, wherein the reactor comprises: an interior formed by a cylindrical vertically oriented elongate shell, a bottom and a cap, wherein the interior is divided by means of internals into the backmixed zone, the zone of limited backmixing and a cavity, a first cylindrical internal element which in the interior extends in the longitudinal direction of the reactor and which delimits the zone of limited backmixing from the backmixed zone, backmixing-preventing second internal elements in the form of random packings, structured packings or liquid-permeable trays arranged in the zone of limited backmixing and a third internal element which in the interior extends in the longitudinal direction of the reactor and is open at the bottom, wherein the third internal element forms the cavity in which gas bubbles collect and do not escape upwards, thus preventing the volume of the cavity from being occupied by liquid and reducing the reaction volume. The reaction volume of the reactor used in the process can be reversibly reduced in simple fashion. The invention further relates to a process for adapting the reaction volume of a reactor suitable for performing a gas/liquid biphasic high-pressure reaction having an outlet for a liquid reaction product in which an internal element is arranged so as to form a cavity open at the bottom in which gas bubbles collect and do not escape upwards, thus preventing the volume of the cavity from being occupied by liquid and reducing the reaction volume.

A reactor for coating particles includes one or more motors, a rotary vacuum chamber configured to hold particles to be coated, wherein the rotary vacuum chamber is coupled to the motors, a controller configured to cause the motors to rotate the rotary vacuum chamber about an axial axis of the rotary vacuum chamber such that the particles undergo tumbling agitation, a vacuum port to exhaust gas from the rotary vacuum chamber, a paddle assembly including a rotatable drive shaft extending through the rotary vacuum chamber and coupled to the motors and at least one paddle extending radially from the drive shaft, such that rotation of the drive shaft by the motors orbits the paddle about the drive shaft in a second direction, and a chemical delivery system including a gas outlet on the paddle configured inject process gas into the particles.

The invention discloses a method for producing bio-fuel (BF) from a high-viscosity biomass using thermo-chemical conversion of the biomass in a production line (10) with pumping means (PM), heating means (HM) and cooling means (CM). The method has the steps of 1) operating the pumping means, the heating means and the cooling means so that the production line is under supercritical fluid conditions (SCF) to induce biomass conversion in a conversion zone (CZ) within the production line, and 2) operating the pumping means so that at least part of the production line is in an oscillatory flow (OF) mode. The invention is advantageous for providing an improved method for producing biofuel from a high-viscosity biomass. This is performed by an advantageous combination of two operating modes: supercritical fluid (SCF) conditions and oscillatory flow (OF).