Reactors Corning

Figure 12.6 Darcy coefficient of pressure drop versus the Reynolds number in a Corning reactor.

CORNING, Reactor Technologies (2009) Corning Advanced-Flow ... 

Scientists from Politecnico di Milano and Ineos Vinyls UK developed a tubular fixed-bed reactor comprising a metallic monolith [30]. The walls were coated with catalytically active material and the monolith pieces were loaded lengthwise. Corning, the world leader in ceramic structured supports, developed metallic supports with straight channels, zig-zag channels, and wall-flow channels. They were produced by extrusion of metal powders, for example, copper, fin, zinc, aluminum, iron, silver, nickel, and mixtures and alloys [31]. An alternative method is extrusion of softened bulk metal feed, for example, aluminum, copper, and their alloys. The metal surface can be covered with carbon, carbides, and alumina, using a CVD technique [32]. For metal monoliths, it is to be expected that the main resistance lies at the interface between reactor wall and monolith. Corning... 

In the following part, four reactors that have been extensively studied in our lab are described the open plate reactor (OPR) - the Alfa-Laval reactor technology (ART ) plate reactor, the Shimtec reactor from Chart Industries, the Corning (glass reactor), and the DeanHex reactor which has been constructed with SiC and stainless steel. 

Pressure drops have been measured in a Corning glass H EX reactor with pressure sensors located on reactive and utiHty Hnes and estimated for different fluids (water, glucose solutions) at various flow rates, from 2 to 101 h, and various temperature levels (from 20 to 50°C). The results are presented in Figure 12.6. 

Glass Reactors. Available on www.corning.com/r d/emerging tech-nologies/reactors.aspx (accessed March 2009). 

For enzyme uptake studies, 0.1 g of substrate (corn flour or carboxym-ethylcellulose) and 24 mL of buffer were added to a 40-mL jacketed reactor. The temperature was maintained at 52 2°C using a water bath. A 1.5-mL "blank" sample was collected from the reaction mixture and added to 3 mL of the dinitrosalicylic acid (DNS) reagent. Then 500 pL of the soluble enzyme was added to the reactor to initiate the reaction. Samples were collected every 3 min, and the DNS assay (4) was performed for all the samples. One unit of enzyme releases 1 pmol of reducing groups/min, the absorbance of which can be measured at 540 nm. Thus, the amount of activity transferred to the support can be determined from the sugar pro-... 

Kinetics studies were conducted at 65 1°C in a jacketed batch reactor. Five hundred milliliters or 1 L of buffer was added to the reactor and heated to the assay temperature. The buffer pH was chosen according to the optima specified by the enzyme manufacturers. Corn flour (100-300 g/L) was then added to the reactor, along with a specified quantity of either soluble or immobilized amylase to initiate hydrolysis. Samples were collected at regular intervals over 30-60 min, and centrifuged to separate solids. The supernatant was analyzed for sugar content by measuring the %Brix with an optical refractometer. 

Stirred tanks are typically used for the thermochemical pretreatment. To simulate flow of corn stover slurries in stirred tanks, the rheologic properties of these suspensions must be known. The corn stover slurries in stirred tank reactors typically range from 10 to 40% solids (3). 

Every 4 d, the reactor s contents are sent to a series of pressure filters to remove residual solids from the product sugar stream. In the batch configurations, the filter cake is discarded and the saccharification vessels are charged with fresh pretreated corn stover and enzyme. In the semibatch configuration, the filter cake is returned to the saccharification vessels, and fresh corn stover (either with or without additional cellulase at 5 FPU/g of cellulose) is added to restore the mass of products removed as filtrate. After every third filtration, the filter cake is discarded and the saccharification vessels are loaded with fresh pretreated corn stover and enzyme. 

Corn steep liquor (CSL), a byproduct of the com wet-milling process, was used in an immobilized cell continuous biofilm reactor to replace the expensive P2 medium ingredients. The use of CSL resulted in the production of 6.29 g/L of total acetone-butanol-ethanol (ABE) as compared with 6.86 g/L in a control experiment. These studies were performed at a dilution rate of 0.32 hr1. The productivities in the control and CSL experiment were 2.19 and 2.01 g/(Lh), respectively. Although the use of CSL resulted in a 10% decrease in productivity, it is viewed that its application would be economical compared to P2 medium. Hence, CSL may be used to replace the P2 medium. It was also demonstrated that inclusion of butyrate into the feed was beneficial to the butanol fermentation. A control experiment produced 4.77 g/L of total ABE, and the experiment with supplemented sodium butyrate produced 5.70 g/L of total ABE. The butanol concentration increased from 3.14 to 4.04 g/L. Inclusion of acetate in the feed medium of the immobilized cell biofilm reactor was not found to be beneficial for the ABE fermentation, as reported for the batch ABE fermentation. 

The reactor consisted of a 300-mL stainless steel pressure vessel (Parr, Moline, IL) (Fig. 1). The vessel was loaded with prewetted corn stover (at desired moisture content). The vessel was topped up with stainless steel spheres (approx 1 mm in diameter) to occupy the void space and thus minimize transformation of the ammonia from liquid to gas during loading. 

Impact of Fluid Velocity on Hot Water Only Pretreatment of Corn Stover in a Flowthrough Reactor... 

Figure 2 presents total dissolved mass yields as a function of reaction time for hot water only pretreatment of com stover in the smallest-diameter and largest-diameter reactors. Total dissolved mass yields increased with reaction times with about 45% of the original total mass dissolved after 20 min for hot water only flowthrough pretreatment of corn stover at 200°C. 

Scheme 26 Selective nitration investigated under flow by DSM using a Corning Incorporated glass reactor.

Off-gas analyses were done by mass spectrometry and reactor effluent samples were analyzed by glc. Most of the glc work was done with an 8-foot 1/4-inch OD column containing 10% SE-30 on acid washed Chromsorb W. However, the separation of n-propyl-benzene from cumene had to be done with a dual 3/16-inch copper column consisting of a 12-foot section having 10% Bentone 34 and 10% Dow Corning silicone gum 550 on 60-80 mesh acid washed Chromsorb W and a 6-foot section containing 20% Apiezon L on 60-80 mesh acid washed Chromsorb P. 

Altshuller, D. Design equations and transient behaviour of the counter current moving bed chromatographic reactor, Chem. Eng. Corn-man., 1983, 19, 363-375. 

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