Sequential batch mode

Further, the authors were able to perform similar reactions on p- and /n-dibro-mobenzenes at 20°C, which is a significant improvement in comparison to batch mode conditions that demand temperatures below —48°C. They have applied the same four-membered system for sequential introduction of two lithium atoms to the... 

Constant-volume batch diafiltration is the most efficient process mode. Sequential batch diafiltration is a series of dilution-concentration steps. Continuous diafiltration practiced in one or more stages of a cascade system has the same volume turnover relationship for overall recoveries as sequential batch diafiltration. The residence time however is dramatically reduced. If recovery of permeable solids is of primary importance, the permeate from the last stage may be used as diafiltration fluid for the previous stage. This countercurrent diafiltration arrangement results in higher permeate solids at the expense of increased membrane area. 

Reliability. The robustness of SFE as a routine technique is shown in Table XIV. These data were generated by loading a sample tray and the samples were run overnight with the help a robotic manipulator. The celite was spiked with the water in batch mode but extracted sequentially. It can be seen from the data that having the samples sitting at room temperatures had no deleterious effects upon... 

Laboratory scale-up in single-mode reactors to produce gram amounts of material can be performed either by the above-mentioned sequential batch processing using various vessel sizes (up to 50 mL) or by employing CF or SF reaction cells (5-50 mL). Conversely, multimode instruments allow for parallel synthesis or applications in large batches up to 1 L total volume and even CF and SF approaches utilizing > 300 mL cells (see below). 

We give only a short description of the three supply chain configurations and their simulation models for details we refer to Persson and Olhager (2002). At the start of our sequential bifurcation, we have three simulation models programmed in the Taylor II simulation software for discrete event simulations see Incontrol (2003). We conduct our sequential bifurcation via Microsoft Excel, using the batch run mode in Taylor II. We store input-output data in Excel worksheets. This set-up facilitates the analysis of the simulation input-output data, but it constrains the setup of the experiment. For instance, we cannot control the pseudorandom numbers in the batch mode of Taylor II. Hence, we cannot apply common pseudorandom numbers nor can we guarantee absence of overlap in the pseudorandom numbers we conjecture that the probability of overlap is negligible in practice. 

Most PTC reactions are carried out on an industrial scale in the batch mode in mixer-settler arrangements. In view of the reactor design in the liquid-solid-liquid PT-catalyzed reaction, Ragaini and coworkers [147-149] reported the use of fixed-bed reactors with a recycling pump or with a recycling pump and an ultrasonic mixer, and emphasized the importance of effluent recycle concept. Schlunt and Chau [150] reported the use of a cyclic slurry reactor, which allowed the immiscible reactants to contact the catalyst sites in controlled sequential steps. However, for triphase reactions in liquid-liquid systems where... 

Bioreactors are operated in discontinuous mode, with a sequential or continuous feed of the substrate (fed-batch operation) or in continuous mode. The choice of the operating mode depends mainly on the reaction characteristics ... 

Sometimes batch and continuous flow modes can be used together in two stage processes, each stage can be operated differently. This is easy to carry out for two stage processes operated sequentially using storage tanks. Combinations of flow modes for processes with an integrated recycle are less easy, but modifications are possible. 

The CMR and MBRs provided the basis for modern commercial microwave reactors, including robotically operated automated systems that are now widely employed in synthetic research and pilot-scale laboratories in academia and industry [13]. Since 2000, commercial microwave reactors have become available. Batch systems, produced by three major companies in Italy and Germany, Sweden and the United States, typically operate on a scale from 0.5 mL up to 2 L. Other companies based in Austria, Poland and Japan have also recently entered the market. Systems possessing either multimodal or monomodal cavities are produced with one recent addition being a single unit capable of performing in either mode as required. Microwave reactors are employed extensively in chemical discovery where successive reactions can be performed rapidly in parallel or sequentially. One manufacturer recently estimated that about 10000 reactions per week were performed in its systems alone. This indicates the extent to which microwave chemistry in closed vessels has dramatically influenced approaches to synthesis. 

There are many variants of analytical flow systems, e.g., segmented flow analysis, flow injection analysis, sequential injection analysis, multisyringe flow injection analysis, batch injection analysis, mono-segmented flow analysis, flow-batch analysis, multi-pumping flow analysis, all injection analysis and bead injection analysis, all of which have acronyms [176]. In view of the existence of several common features, however, all flow analysers can be broadly classified as either segmented or unsegmented, with the most common example of the later mode being the flow injection analyser. 

Although batch emulsion polymerization is not frequently used, it will be discussed first because it is easier to imderstand as the fundamental processes occur in a sequential way, whereas in the semicontinuous and continuous modes the processes occur simultaneously. 

COD (chemical oxygen demand) removed [27]. The process can be operated in either a batch [28] or continuous [29] mode within a single unit, where adsorption, separation, and regeneration occur either continuously within different zones of the unit or sequentially in batch operation. 

The polymerisation reaction is carried out in a batch or in a continuous mode depending on the specific process (details in Section 8.2). The reactor is charged with solvent and catalyst. Depending on the targeted polymer, monomers are added simultaneously or sequentially. Where a random copolymer is required, a structure modifier, usually an ether, is added. These chemicals have the additional benefit of increasing the amount of 1.2 polymerisation of the butadiene, i.e. they increase the vinyl content. 

---