Feedstock specification

Under typical chlorination conditions, most elements are chlorinated. Therefore, for every metric ton of titanium tetrachloride produced, lower grade feedstocks requite more chlorine. Minor impurities such as alkaline-earths, where the chlorides are relatively involatile, may either inhibit bed-fluidization or cause blockages in the equipment and requite particular consideration regarding feedstock specification. 

The first commercial trialkyl phosphate esters (TAP) were tricresyl phosphate (TCP) and trixylenyl phosphate (TXP), referred to as "natural" phosphate esters because the cresols and xylenols used as raw materials are derived from petroleum oil or coal tar (Marino and Placek 1994). These products are not commercially significant at present however, at waste disposal sites, contaminants from older product formulations may be encountered, particularly those containing the neurotoxic tri-o/T/io-cresyl phosphate isomer. "Synthetic" phosphate esters are derived from synthetic feedstocks. Specific synthetic reactions have been developed to produce triaryl, trialkyl, and alkyl Aryl esters. The triaryl phosphates are currently... 

Cf compression ratio that should be used for a lower density feedstock resin Cpeiiets compression ratio used for a pellet feedstock specific heat of the solid resin diameter at the barrel wall local diameter at the screw core... 

It is also worth noting that although the IFP group reported on different mixed oxide catalytic systems, namely Ti and A1 mixed oxides [6], Bi, Ti and A1 mixed oxides [7], Sb and A1 [8] and Zn, Ti and A1 [9], none of them is able to convert the FFAs eventually present in the oil. Feedstock specifications are therefore demanding also for these basic catalytic systems. 

In chemical reaction engineering, data and models obtained from applied chemical kinetics are used to design, optimize and control a chemical reactor by taking into account the feedstock specifications and the technical and economic constraints (Table 2). Whereas, in applied... 

The degree zero in empirical reaction modelling consists of plotting commercial indicators of interest, such as yields, selectivities, costs, profits, etc., versus more or less independent (i.e. adjustable) variables, such as feedstock specifications, reactor characteristics, operating conditions and so on. This approach needs an extensive data basis and can be used only in interpolation. 

Materials (ASTM).94 In addition, the National Renewable Energy Laboratory95 (NREL) has developed and validated a collection of standard laboratory analytical procedures specifically for the compositional analysis of biomass including, but going beyond those of the ASTM. These wet chemical methods of analysis are based on the fractionation of the biomass sample and the isolation of purified fractions that can be quantified using conventional analytical instruments.96 These methods are primarily used in feedstock-specific portfolios containing analysis methods for each of the relevant constituents. In most cases, these portfolios enable the identification and quantification of greater than 95 percent of the dry mass of biomass feedstock and biomass-derived materials. 

Plastic feedstock specifications are extremely important in order to obtain satisfactory and consistent fuel quality (see Table 15.2). A rigid incoming feedstock specification (IFS) ensures that limits are placed on critical contaminants. The critical contamination is based around the so-called hetero-atoms . These are listed below in order of priority ... 

Operation of the biomass fast pyrolysis pilot plant with DC-III and woody feedstocks, specifically mixed softwoods (mainly pine) and hardwoods, revealed the following ... 

A feedstock specification or product specification provides the data that give adequate control of feedstock behavior in a refinery or product quality. Thus a specification offers the luxury of predictability of feedstock behavior in a refinery or predictability of product quahty (therefore, product behavior) relative to market demand. Ultimately, feedstock behavior and/or product quality is judged by an assessment of performance. And it is performance that is the ultimate criterion of quality. It is therefore necessary to determine those properties, the values of which can be established precisely and relatively simply by inspection tests in a control laboratory, that correlate closely with the important performance properties. 

Although carbon black in some form can be made from any hydrocarbon refinery stream, many years of experience and experimentation have narrowed the feedstock specifications greatly from the standpoint of both quality and yield of product. Typical inspection tests are listed in Table II. 

Carbon monoxide purity requirements vary considerably depending on end products. By-products formed during the production of phosgene can have a deleterious effect on downstream products formed by the phosgenation reaction. In general, the requirements for polycarbonates are more stringent then for isocyanates. The recommended CO feedstock specifications for each downstream product are given in the section for each product. 

The feedstock specifications for carbon monoxide used in production of polycarbonates by the phosgenation route are shown in Table 3 [3]. 

The use of zeolites in the organic chemical industry took a great step forward with their adoption in the isomerization of w-xylene to p- and o-xylenes used in the manufacture of terephthalic acid and phthalic anhydride, respectively. The ZSM-5 catalysts developed by Mobil Corporation became the prime catalysts for this process all over the world. Remember, however, that catalysts are developed specifically to meet certain criteria and to suit a given feedstock specification. We illustrate this through the following example. 

Ballestra assumes organic feedstock specifications as outlined in chapter 3, raw materials For linear alkylbenzene see 3.6.1. alkylbenzene quality ... 

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