Titanium chloride-Magnesium

When the flowsheet is complex and involves numerous process steps, a low-energy efficiency will result. The metals titanium and magnesium are difficult to reduce, and their production involves chloride intermediates which are produced from the oxide raw materials. Titanium requires magnesium or sodium as the reducing agent, and these metals are themselves obtained by electrolytic processes which are energy-intensive. Another feature which may add to the complexity of the process flowsheet is the need to separate impurities and by-products using special processes this is the case with copper, lead, and nickel. 

Fig. 2. Sequential extraction of Arsenic (MG-magnesium chloride, PHOS-sodium hypo phosphate, HCL-hydrocihoric acid, OX-oxalic acid, ToCEB- titanium chloride with EDTA, NIT- nitric acid).

In Figure 23—6, polymer grade ethylene and any comonomers are blown into the-base of a fluidized bed reacton A very reactive catalyst (based on-titanium and magnesium chlorides) is injected and admixes with the ethylene. Polymerization takes place at 150-212 F and 300 psi, and polymer particles stay in the fluidized state as the ethylene swirls through the reactor. Since the temperature is controlled at or below the melting point, the particles form a white powder. 

Major constituents (greater than 5 mg/L) Minor constituents (O.Ol-lO.Omg/L) Selected trace constituents (less than 0.1 mg/L) Bicarbonate, calcium, carbonic acid, chloride, magnesium, silicon, sodium, sulfate Boron, carbonate, fluoride, iron, nitrate, potassium, strontium Aluminum, arsenic, barium, bromide, cadmium, chromium, cobalt, copper, gold, iodide, lead, Uthium, manganese, molybdenum, nickel, phosphate, radium, selenium, silver, tin, titanium, uranium, vanadium, zinc, zirconium... 

Solutions of low-valence titanium chloride (titanium dichloride) are prepared in situ by reduction of solutions of titanium trichloride in tetrahydrofuran or 1,2-dimethoxyethane with lithium aluminum hydride [204, 205], with lithium or potassium [206], with magnesium [207, 208] or with a zinc-copper couple [209,210]. Such solutions effect hydrogenolysis of halogens [208], deoxygenation of epoxides [204] and reduction of aldehydes and ketones to alkenes [205,... 

Methylmagnesium chloride Magnesium, chloromethyl- (8, 9) (676-58-4) Chloromethyltitanocene Titanium, chlorodi-Ti-cyclopentadienylmethyl- (8) Titanium, Chlorobis(Ti -2,4-cyclopentadien-1-yl)methyl- (9) (1278-83-7)... 

It may be interesting, in connection with the ethylene/propylene copolymers mentioned above, to present here some homogeneous Ziegler-Natta catalysts formed by soluble complexes of titanium and magnesium chlorides with alkyl phosphates as catalyst precursors and alkylaluminium compounds as activators (TiCl4)x.(MgCl2)r [0=P(0Bu)3]3-A1(/-Bu)3 and Cl3TiOMgCl-[0 = P(0Bu)3]3- A1(z -Bu)3 (Al/Ti molar ratio of ca 10 1). These catalysts have been used for random ethylene/propylene copolymerisation [73],... 

HC Mixture-hexachloroethane, zinc, inorg perchlorate amm chloride FM-titanium tetrachloride BM Mixture-zinc, carbon tetrachloride, sodium chloride, amm chloride magnesium carbonate... 

The activity of the catalyst in the olefin polymerization changes a wide range mainly with the variation of the number of ACs. This number depends on the nature and crystalline structure of the transition metal compound, the presence of a support and catalyst modifier, the nature of a cocatalyst, and the polymerization conditions. The most pronounced increase of the number of active centers (up to nearly half of the total content of titanium in the catalyst) is achieved by supporting titanium chlorides on anhydrous highly dispersed magnesium chloride. Catalysts of this type show the highest activity amongst all known catalytic systems used for olefin polymerization. 

As a catalyst for the ring condensation Lewis acids such as for instance zinc chloride, zinc bromide, boron trifluoride, ferric chloride, stannic chloride, titanium chloride or iodine are used, zinc chloride and zinc bromide having proved to be more particularly suitable. Water binding substances such as neutral substances as for instance magnesium sulfate, sodium sulfate, calcium sulfate or molecular sieves may be used, the last-named having proved more particularly suitable. 

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