A method for measuring the concentrations of species present at at least one point of a separation unit operating in simulated moving bed (SMB) mode, or a hybrid separation unit employing a step for simulated moving bed (SMB) separation and a step for crystallization, by calibration by inline acquisition of Raman spectra for different mixtures; analysis by inline signal processing of the Raman spectrum.

A system for separating components of a fluid containing at least a first component and a second component includes a device having an inlet for introducing the fluid into the device, a first outlet for directing the first component of the fluid from the device, and a second outlet for directing the second component of the fluid from the device. A material that has a gradient in properties is located in the device between the inlet and the first and second outlets. The material has a first portion with an affinity for the first fluid component and a second portion with an affinity for the second fluid component. The first portion is positioned with relation to the first outlet such that the first component is directed from said device through the first outlet. The second portion is positioned with relation to the second outlet such that the second component is directed from the device through the second outlet.

The present invention relates to dual extract flush for feeds for xylene extraction processes. More specifically, the present invention relates to dual extract flush for feeds for simulated moving bed extraction processes. It decouples line flush in and line flush out, providing a means for optimizing each flush independently. This scheme will allow for minimizing each bedline and flushing each according to its own bedline volume, which will minimize any additional non-ideal compositions added to the chambers or downstream fractionation.

The present invention describes a device for supplying or collecting from a column forming part of an assembly of columns in series, for use in a simulated moving bed separation process. The present device can be used to very substantially reduce the non-selective volumes in each column.

A valve block includes a fluid-transfer plate with multiple inlet bores connecting to a common inlet channel, and multiple outlet bores connecting to a common outlet channel. The inlet bores and the outlet bores are arranged in a curved shape. The valve block also includes a pressure plate and diaphragm aligned and connected to the fluid-transfer plate in a way that allows pressurized material in the pressure plate to control the state of the channels formed by the inlet and outlet bores.

Certain embodiments described herein are directed to devices that can be used to control fluid flow through one or more detectors. In some configurations, the device can be configured as a manifold that can receive a positive pressure to decouple the flow of fluid through a chromatography column from fluid flow through a detector. In certain configurations, sample flow can be accelerated into a detector cell comprising one or more filaments.

A method for measuring the concentrations of species present at at least one point of a separation unit operating in simulated moving bed (SMB) mode, or a hybrid separation unit employing a step for simulated moving bed (SMB) separation and a step for crystallization, by calibration by inline acquisition of Raman spectra for different mixtures; analysis by inline signal processing of the Raman spectrum.

Disclosed is a continuous process for the purification of steviol glycosides extracted from the dried stevia leaves using continuous simulated moving bed processes and nanofiltration without the addition of organic solvents to obtain a purified steviol product comprising sweet steviol glycosides. The sweet steviol glycosides can be used as substitutes for caloric sweeteners in beverages and in other food items.

Provided herein in some embodiments is a column including a housing assembly and a cartridge assembly. The housing assembly can include a housing top, a housing bottom, and a housing siding. The housing siding can be fixedly coupled to the housing top and the housing bottom forming hermetic seals therebetween. The cartridge assembly can include a cartridge top, an outer frit, and an inner frit disposed within the outer frit. A toroidal space can defined by the cartridge top, the outer frit, the inner frit, and the housing bottom. The toroidal space can be configured to hold a stationary phase for radial flow column chromatography. Also provided herein in some embodiments is a process including assembling the cartridge assembly, assembling the housing assembly about the cartridge assembly, and pressure testing the column. In some embodiments, the process can further include charging the toroidal space with a stationary phase.

A simulated moving bed process using dual, parallel rotary valves configured or plumbed to be operated independently in which the step times of the rotary valves are staggered. In embodiments, the second rotary valve is programmed to step about halfway through the step time of the first rotary valve. Staggering the step time of the parallel rotary valves, rather than utilizing simultaneous stepping, results in increased net composite paraxylene concentration of the extract stream, allowing for increased capacity of the simulated moving bed process and/or reduced energy consumption.