Abstract:
Process for adiabatically hydrofluorinating hydrochlorocarbons and hydrochlorofluorocarbons in the gaseous phase in the presence of a catalyst that is active at the initial reaction temperature and remains highly selective at the maximum reaction temperature, e.g., a Cr catalyst. The molar ratio of HF to starting compound is at least about 2.5:1. The initial reaction temperature is selected such that the HF in the feed is partially associated but not completely (HF)₆. The catalyst may be unsupported or supported.
Abstract:
Linear C₄+ alkyl mercaptans of high purity are prepared by the reaction of a di-linear(C₄+) alkyl sulfide with hydrogen sulfide at elevated temperature in the presence of an alumina material selected from gamma/eta alumina or gamma/eta alumina impregnated with up to 20% w/w of titania or rhenium oxide.
Abstract:
A process is disclosed for the efficient production of high purity alkane sulfonic acid and/or alkane sulfonyl chloride product wherein a compound of the formula RSX, where X is hydrogen or -SR¹ and R and R¹ are alkyl radicals is continuously reacted with chlorine in aqueous hydrochloric acid to produce a turbulent evolution of hydrochloride gas, passing the reactants through stationary mixing elements to promote plug-flow, and separately withdrawing a product. Apparatus for this process is also disclosed.
Abstract:
This invention relates to novel UV absorbers, their methods of preparation, their use in stabilizing polymers and polymers so stabilized against the degradative effects of UV light. The novel compounds of formula I are oxamides which are substituted on one or both nitrogens with a 2-hydroxy-3-(2H-benzotriazol-2-yl)benzyl group. The 2-hydroxy-3-(2H-benzotriazol-2-yl)benzyl groups are efficient UV absorbing groups and the oxamide group contributes additional light stabilizing, heat stabilizing and metal complexing properties to the compounds. The compounds have low-volatility and are especially useful as UV stabilizers for engineering resins processed at high temperatures.
Abstract:
Shaped, dust-free dry wire drawing compound lubricants having at least one reproducibly controlled dimension and methods for their preparation comprising the steps of conglutinating and pressure forming the lubricant composition.
Abstract:
On prépare un article de verre enrobé en faisant appel à la technique de dépôt en phase gazeuse par procédé chimique, d'un mélange d'un précurseur de l'oxyde d'étain, d'un précurseur du dioxyde de silicium et d'un agent d'accélération tel que le phosphite de triéthyle, à des vitesses de dépôt supérieures à 350Å/sec. sur du verre ayant une température comprise entre 450 et 650 °C. On peut associer la couche de matériau déposée à d'autres couches, de façon à obtenir un article possédant des propriétés spécifiques relatives à l'émittance contrôlée, l'indice de réfraction, la résistance à l'abrasion ou l'aspect.