Raw Materials and Their Preparation

M. J. Kocurek and C. F. B. Stevens, "Properties of Fibrous Raw Materials and Their Preparation," Pulp and Paper Manufacture, 3rd ed., Vol. 1, TAPPI Press, Atlanta, Ga., 1983. 

Fig. 6.11-15 is a diagram of these routes indicating the applicable raw materials and their preparations, the web forming and bonding, the post-treatments (processing of non-wovens) and the type of products [B.107]. 

Ester sulfonates will become more and more interesting in the future because the raw materials for their preparation are fatty acid esters which can be prepared from oils and fats, and thus from renewable resources. They can be used as possible substitutes for surfactants based on petrochemicals. 

Raw Materials and Their Carbonization. The original materials are vitrain-enriched fractions of three different rank caking coals (Table I) and two pitches of different types (Table II), from which certain mixtures have been prepared. 

In the war of 1914-18 these substances had a limited use. On the one hand, the raw material for their preparation (toluol) was too costly, and on the other their lachrymatory power was soon surpassed by that of other substances. 

Ester sulfonates will become more and more interesting in the future because the raw materials for their preparation are fatty acid esters which can be prepared from oils and rats, and thus from renewable resources. They can be used as possible substitutes for surfactants based on petrochemicals. Even today renewable resources play a dominant role as raw materials for surfactants, but only because of the great contribution made by soaps to the production of surfactants. If the soaps are left out of consideration as native surfactants, petrochemistry holds 65-70% of the production of synthetic surfactants [2], But for the future a further increase in the use of renewable raw materials is expected to occur in surfactant production [3]. The main reason for this development is the superior digestibility in the environment of products produced from natural materials. The future importance of the renewable raw materials becomes evident from the fact that even now new plants are cultivated or plants are modified to obtain an improved yield. A new type of sunfiower has been cultivated to obtain a higher proportion of monounsaturated oleic acid compared with doubly unsaturated linoleic acid [4]. 

Activated carbons are made by first preparing a carbonaceous char with low surface area followed by controlled oxidation in air, carbon dioxide, or steam. The pore-size distributions of the resulting products are highly dependent on both the raw materials and the conditions used in their manufacture, as maybe seen in Figure 7 (42). 

Preparation and Properties of Organophosphines. AUphatic phosphines can be gases, volatile Hquids, or oils. Aromatic phosphines frequentiy are crystalline, although many are oils. Some physical properties are Hsted in Table 14. The most characteristic chemical properties of phosphines include their susceptabiUty to oxidation and their nucleophilicity. The most common derivatives of the phosphines include halophosphines, phosphine oxides, metal complexes of phosphines, and phosphonium salts. Phosphines are also raw materials in the preparation of derivatives, ie, derivatives of the isomers phosphinic acid, HP(OH)2, and phosphonous acid, H2P(=0)0H. 

Owing to their numerous actual and potential applications, several ternary and complex systems of these metals, especially of aluminium, have been investigated a few examples of the systematics of Al-Me-X alloys are presented in 5.18 and in Fig. 5.41. Recent contributions to this subject have been given with the study of the systems R-Al-Cu (Riani et al. 2005, and references there in). These rare earth alloys, characterized by the formation of several intermediate phases, are interesting also as raw materials for the preparation of amorphous alloys. Regularities in the trends of their properties have been underlined. The experimental and calculated data relevant to the binary systems Al-Fe, Al-Ni and Fe-Ni have been examined and discussed in a paper concerning the assessment of the ternary Al-Fe-Ni system (Eleno et al. 2006). 

Phospholipid concentration was determined using our modification of Bartlett s procedure (49,53). Cholesterol concentration and purity were determined by HPLC or enzymatically by cholesterol oxidase (49,53). Purity of phospholipids as raw materials, and the extent of their hydrolysis during various steps of liposome preparation and liposome storage, were assessed by TLC and enzymatic determination of the increase in level of nonesterified fatty acids (10,38,49-51,53). 

Molecular spectroscopic techniques have been widely used in pharmaceutical analysis for both qualitative (identification of chemical species) and quantitative purposes (determination of concentration of species in pharmaceutical preparations). In many cases, they constitute effective alternatives to chromatographic techniques as they provide results of comparable quality in a more simple and expeditious manner. The differential sensitivity and selectivity of spectroscopic techniques have so far dictated their specihc uses. While UV-vis spectroscopy has typically been used for quantitative analysis by virtue of its high sensitivity, infrared (IR) spectrometry has been employed mainly for the identihcation of chemical compounds on account of its high selectivity. The development and consolidation of spectroscopic techniques have been strongly influenced by additional factors such as the ease of sample preparation and the reproducibility of measurements, which have often dictated their use in quality control analyses of both raw materials and finished products. 

One would also think that saccharides are more attractive starting raw materials for direct preparation of epoxy resins than hydrocarbons since they already possess oxygen atoms needed for the epoxy rings. Such diepoxy derivatives of hexitols are known compounds, for instance 1,2 5,6-dianhydro-3,4-0-isopropylidene-D-mannitol (XIX). Their preparation, however is difficult and requires 15 to 18 steps which proceed in very low overall yield (17-19). 

Specifications are normally written by QC personnel. They detail the exact qualitative and quantitative requirements to which individual raw materials or product must conform. For example, specifications for chemical raw materials will set strict criteria relating to the percentage active ingredients present, permitted levels of named contaminants, etc. Specifications for packing materials will, for example, lay down exact dimensions of product packaging cartons specifications for product labels will detail label dimensions and exact details of label text, etc. Specifications for all raw materials are sent to raw material suppliers and, upon their delivery, QC personnel will ensure that these raw materials meet their specifications before being released to production (the raw materials are held in quarantine prior to their approval). Final product specifications will also be prepared. As most products are manufactured to conform with pharmacopoeial requirements, many of the specifications set for raw materials/finished product are simply transcribed from the appropriate pharmacopoeia. 

Two studies with raw materials used to prepare parenteral formulations were carried out to show their content of aluminum and arsenic [15,16]. It is possible to see in Figures 2 and 3 that aluminum and arsenic were present in all investigated raw materials. There were also different levels of contamination among the substances. While salts such as NaCl and KC1 presented low aluminum contaminations, phosphates, gluconate, and also citric acid were relatively contaminated. The authors attributed this difference to the affinity of aluminum to the latter substances. Arsenic showed a more uniform distribution of contamination. With the exception of the amino acid tyrosine, the arsenic level in all substances was below 1 qg/g, not exceeding the limits prescribed by pharmacopeias. 

The behavior of the material during the processes is strongly dependent on the characteristics of the starting materials. Their characteristics must also then be measured and quantified. This includes not only the quality of the starting raw materials and excipients, but also in the preparation and packaging before placing the product into the lyophilizer. 

As can be seen from the Global Reactive Chemicals Standard, all existing chemical processes will have a Reactive Chemicals/Process Hazard Analysis review on a predefined periodic basis. In addition, every new plant Production Leader should review their process with the Reactive Chemicals Committee within 90 days of assuming responsibility for a pilot or production plant. Prior to the review, the Leader should acquire training on the chemistry and processes that they are working with. This should include an evaluation of raw materials, processes, products and waste to understand any potential reactive chemical hazards. They should review and be prepared to answer questions from the completed and updated RC/PHA protocol questionnaire as well as other relevant materials in their plant Process Safety Folder, such as F EI, CEI, etc. The review should cover all auxiliary operations to the process such as raw material and product storage drum, tank car and truck loading. 

Examples of some typical prepolymer materials and their raw material derivatives are given in Table I. Polymer manufacture schemes for radiation curable and conventional coatings are in Figures I and II. Qualitative comparison of a relative energy input intensity for preparation of radiation curable and conventional coatings are given in Tables II, III, and IV,... 

Because of their increasing use worldwide, plant materials used in over-the-counter preparations, home remedies, or as raw materials for pharmaceutical preparations are receiving more and more attention. In 1998, WHO published a book. Quality Control Methods for Medicinal Plant Materials to fulfill the needs of quality control laboratories and to provide a basis for the development of national standards. ... 

The structure of foods comes from nature or it is imparted through processing, storage, or during preparation. The structure of processed foods evolved throughout the centuries, mostly by trial-and-error, based on a few raw materials and simple transformations induced by mankind. Structure is important in foods because it can be related to physical properties and, by extension, to their quality and acceptability. 

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