Theoretical balance yield

Theoretical balance yield BA, is given by the ratio between the moles of the target product and the total moles of the primary raw materials (PRM), including all reactants involved in the stoichiometry of the synthesis route. 

The calculation shows that the stoichiometric yield RY is acceptable, but the theoretical balance yield BAt poor, because catalyst complex lost after reaction. A significant improvement would be the use of solid catalyst. Other alternative is regeneration of A1C13 complex by recycling. The two solutions would lead to the same theoretical yield, but with different costs. Therefore, a deeper investigation should take into account a cost flow analysis too. More details can be found in Christ [2]. 

Material Flow Analysis (MFA). It is possible however to estimate a productivity parameter based on the reaction equation (ideal model). This parameter is the theoretical balance yield BA, defined as follows ... 

BA (real balance yield) and BA, (theoretical balance yield) play a central role in material flow analysis MFA (Trade Mark of BTC Dr. Dr. Steinbach GmbH, Mannheim, Germany). 

Therefore, BA can be seen as a productivity function that should be maximised by design. For example, the excess of reactant can give higher stoichiometric yield RY, but lower real balance yield BA. Increasing EAp to the theoretical limit of one is an objective of process design. This can be achieved by replacing steps involving unrecoverable auxiliary chemicals with operations where the recycle of materials is possible. 

Example This equation is obtained in distillation problems, among others, in which the number of theoretical plates is required. If the relative volatility is assumed to be constant, the plates are theoretically perfect, and the molal liquid and vapor rates are constant, then a material balance around the nth plate of the enriching section yields a Riccati difference equation. 

The filtrates are combined, cooled, and extracted with three successive 200 cc portions of ether. The pH of the filtrate is then raised to 3.5 with sodium hydroxide and the filtrate extracted with six successive 200 cc portions of ether to yield the balance of the product. The crude para-aminobenzoic acid product is recovered by evaporation of ether and is suspended in hot benzene, cooled and filtered to remove benzoic and toluic acids together with small amounts of impurities soluble in the filtrate. Recrystallization of the product from 200 cc of water yields 14.5 grams of light tan needles of para-aminobenzoic acid having an acid number of 411 (theoretical value 409). 

The component with the lowest equilibrium constant is called the key component in the stripping process, because it yields the largest value of Vnjm- This largest value is the true minimum air flowrate, whereas the actual air flowrate should be selected at 1.20 to 2.0 times the minimum. This becomes a balance between fewer theoretical stages at actual air flowrate, yet requires a larger diameter column to carry out the operation. 

To calculate percentage yield, one needs to know the theoretical value that can be obtained, based on material balance, and if 100% of the reactant(s) is converted to product. After obtaining the experimental value (actual yield), divide it by the theoretical value, then multiply by 100 to get percentage yield.8... 

The percent yield is 100 times the amount of a product actually prepared during a reaction divided by the amount theoretically possible to be prepared according to the balanced chemical equation. (Some reactions are slow, and sometimes not enough time is allowed for their completion some reactions are accompanied by side reactions which consume a portion of the reactants some reactions never get to completion.) If 3.00g C6H,Br is prepared by treating 3.00g ChHl2 with excess Br2, what is the percent yield The equation is... 

Astronomical Observatory, were used to carry out the calculations of theoretical equivalent widths of lines, synthetic spectra and a set of plane parallel, line-blanketed, flux constant LTE model atmospheres. The effective temperatures of the stars were determined from photometry, the infrared flux method and corrected, if needed, in order to achieve the LTE excitation balance in the iron abundance results. The gravities were found by forcing Fe I and Fe II to yield the same iron abundances. The microturbulent velocities were determined by forcing Fe I line abundances to be independent of the equivalent width. For more details on the method of analysis and atomic data see Tautvaisiene et al. (2001). 

Balanced equation PC13 + Cl2 - PC15 Step 1. Calculate the theoretical yield of PC15. 

Hirano, A., Hon-Nami, K., Kunito, S., Hada, M., and Ogushi, T. (1998). Temperature Effect on Continuous Gasification of Microalgal Biomass Theoretical Yield of Methanol Production and its Energy Balance, Catalysis Today 45. pp. 399-404. 

Theoretical analyses of interfacial debonding and frictional pull-out in the fiber pull-out test were initially modeled for ductile matrices (e.g. tungsten wire-copper matrix (Kelly and Tyson, 1965, Kelly, 1966)) assuming a uniform IFSS. Based on the matrix yielding over the entire embedded fiber length, as a predominant failure mechanism at the interface region, a simple force balance shown in Fig. 4.19 gives the fiber pull-out stress, which varies directly proportionally to the cylindrical surface area of the fiber... 

According to the balanced equation, 1 mol of product is produced per mol of reactant, so we know that 0.470 mol of isobutylene can theoretically yield 0.470 mol of MTBE. To find the mass of this MTBE, we do a mole-to-mass conversion ... 

Because we started with 0.870 mol of ethyl alcohol, and because the balanced equation indicates that 2 mol of ethyl alcohol yield 1 mol of diethyl ether, we can theoretically obtain 0.435 mol of product ... 

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