Imperial Chemical Industries Limited

Other

John Graham Allen

Michael John McDermott

Thomas A Ryan

Keith Jones

John A Stott

Daniel Howard Legg

Massimino Ugo Pilotti

Helen Marie Schoelzel

Peter Gordon Wright

Process for the recovery of hydrogen fluoride (HF) from a mixture, preferably an azeotropic mixture, of HF with water and/or an organic compound such as 134a, 125 or 133a, which comprises contacting the mixture with lithium fluoride or an alkaline earth metal fluoride to form a metal fluoride-hydrogen fluoride compound (e.g. lithium bifluoride, LiHF.sub.2), separating the compound and decomposing it to liberate hydrogen fluoride therefrom. The process is useful for recovering HF from azeotropic or azeotropic-like mixtures.

Hydrogen fluoride recovery process

Catalyst production for use in a process for fluorination of hydrocarbons

A process for the treatment of acidic fluoride-containing solutions to neutralize them and to remove fluoride ion in the form of a readily filterable precipitate which comprises mixing the acidic solution with a suspension of an alkaline earth metal oxide or hydroxide, wherein a flocculating agent is incorporated in the acidic solution before mixing thereof with the alkaline earth metal oxide or hydroxide.

Treatment of dilute acidic solutions

A payload can be transferred between two relatively movable stations for example two ships using a winch system having an inhaul winch and an outhaul winch. The barrel of the outhaul winch is driven by an outhaul motor through a torque convertor such that the outhaul winch provides pull on the trolley 16 regardless of the sense of rotation of the outhaul winch barrel. A control system is used to control the speed of the inhaul winch barrel either to retrieve cable or to pay out cable. Thus, the speed of the trolley 16 is controlled by the speed at which the inhaul winch barrel is driven. The outhaul winch either can be at the same station as the inhaul winch or can be at the opposite station to the inhaul winch.

Winch system

Photosensitive polymeric compositions comprising a copolymer of (a) vinyl alcohol units and (b) vinyl ester units derived from the structure ##STR1## in which R is a divalent organic group, R.sup.1, R.sup.2 and R.sup.3 are organic substituents and X is an anion are disclosed. The ratio of (a) to (b) units is from 1:100 to 1000:1, units (a) and (b) together forming at least 80% of the copolymer. These copolymers are useful in forming films sensitive to ultra-violet radiation.

Radiation sensitive vinyl hydrophilic copolymers

Salts of N,N'-bis(p-cyanophenyl)-4,4'-bipyridylium are prepared by contacting an N,N'-bis(2,4-dinitrophenyl)-4,4'-bipyridylium salt with p-cyano-aniline in an inert polar medium.

Method of preparing an N,N'-bis(p-cyanophenyl)-4,4'-bipyridylium salt

An electrochromic medium and electrochromic devices containing such mediums comprising an electrochromically active material, an auxiliary redox system comprising reversibly oxidizable metallic ions, for example iron, a complexing agent for the metallic ions, particularly a carboxylic acid such as tartaric acid, and an inert solvent.

Electrochromic device and medium therefor

A device for the control of light transmission or reflection comprises one or more working electrodes, preferably arranged to form a display and having radiation transmission or reflection properties, an active material comprising an N(p-cyanophenyl) substituted derivative of a compound, usually bicyclic, having two conjugated nitrogen-containing rings in contact with the working electrode surface, a counter electrode, also in contact with the active material and ferrous ammonium sulphate as an auxiliary redox system.

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Warrington, United Kingdom

John Graham Allen