Another new zeolite catalyst

299 to Conversion" and Dr. P. A. Jacobs on "Recent Catalvsis Develooments". In addition to papers on methods of coal liquefaction and gasification, many of the papers are concerned with catalytic routes for the conversion of coal-derived materials to useful chemicals. The progranme also includes a Workshop (by invitation) on Heterogeneous Catalysis and visits are being arranged to the Sasol Two and Three Fischer-Tropsch plants at Secunda, to the AECI olant at Modderfontein for the'production of ammonia from coal and to the AECI Plant at Sasolburo for the oroduction bf PVC. It is hoped that a'full report on the Conference will appear in Applied Catalysis in due course.

Another

New Zeolite

Catalyst

Imperial Chemical Industries have applied for a patent (European Application 42, 226) for a new zeolite for hydrocarbon processes, especially hydrocarbons from methanol. The preferred formulation is 0.5 - 1.5 Na20 : Al203 : 70 (or more) Si02. The Na cations can be replaced by any other monovalent metal or hydrogen, Al by Fe, Ga or B and Si by Ge. A wide range of shape selective catalysts may be prepared from a variety of metals by ion exchange or impregnation.

Fixed Fluidised Reactor

Bed Fischer-Tropsch

When designing "dry" (as distinct from "slurry") fluidised catalyst reactors one has the choice between the circulating fluidised bed (CFB) and the fixed fluidised bed (FFB). The Synthol reactors at Sasol are of the CFB type and are commercially proven. During the 1950's, FFB reactors were built for the Fischer-Tropsch demonstration plant at Brownsville in the USA. Initially these reactors were beset by catalyst fluidisation problems and, although these were reputedly solved, the reactors were not commercially proven because the plant was shut down for other (economic) reasons. Believing the FFB reactor system to have merit and realising that good catalyst fluidisation is a key factor, research was and still is being carried

out at Sasol to study the fluidisation characteristics of the heavy powdered iron catalyst used commercially. Cold model studies were carried out on reactors varying from 5 to 65 cm ID and the influence of fluidisation promoter, gas distribution nozzle design and of internal surfaces (e.g. heat exchange tubes) on the quality of fluidisation was studied. Based on these studies, it was decided to build a demonstration FFB reactor. The design was carried by the Badger Company and the reactor will be on line early in 1983 in the Sasol One plant at Sasolburg. The Conversion of Gasification to Motor Fuels

Tars

The Lurgi coal gasifiers produce as a byproduct tars which range from light naphtha to nondistillable pitch. In the Sasol process, the highly aromatic light tar naphtha has always been catalytically hydrofined and added to the gasoline pool, where it is a welcome component since the straight run Synthol Fischer-Troosch qasoline onlv contains ca 15% ring-compounds.The heavy tar distillates (creosotes) have been sold as such but, with the huge expansion of the Sasol process, the local market cannot absorb the additional creosote production. Pilot-plant runs at Sasol showed that the creosote was readilv hvdrofined over typical Ni-Mo-Al2b3 catalysts to produce an in-soecification diesel fuel. As long'as only distillates were fed, the catalyst deactivation rates were low. This process is now being connnercialised and the creosote hydrogenation process, designed by Union Oil, is due to come on stream in 1983.

Organo-polysiloxane Inorganic Complexes

Supports

for

Degussa AG (Frankfurt-am-Main) have announced a new series of hetergenised complex catalysts containing Rh, Ir, Ru and Pt which can be used in place of homogeneous catalysts. Compared with homogeneous catalysts, these catalysts are more easy to separate and recycle and the noble metals can readily be recovered from them; in addition,