Abstract: Dimethyl carbonate and methyl tert-butyl ether are prepared by a continuous integrated process comprising:a) feeding methanol, carbon monoxide and oxygen into a reaction environment maintained under methanol oxidative carbonylation conditions, to form a liquid reaction mixture containing dimethyl carbonate and unaltered methanol;b) at least partly eliminating the water from the reaction mixture of stage a);c) feeding the dehydrated mixture of stage b) and isobutene, or a hydrocarbon fraction containing isobutene, into a reaction environment maintained under etherification conditions, to form a liquid reaction mixture containing dimethyl carbonate and methyl tert-butyl ether; andd) recovering the dimethyl carbonate and methyl tert-butyl ether from the reaction mixture of stage c).

Abstract: Methyl tert-butyl ether of high purity is prepared by reacting methanol with isobutylene in the presence of an acid ion exchange resin in two stages by feeding methanol and isobutylene mixed with other hydrocarbons to the respective members of a pair of interconnected reactors so that the quantity of alcohol present in one of the reactors is in excess of the stoichiometric equivalent of the quantity of isobutylene therein, while the quantity of isobutylene present in the other reactor is in excess of the stoichiometric equivalent of the quantity of methanol therein, and the methyl tert-butyl ether so formed is recovered through distillation.

Abstract: Isobutylene is separated from a stream of C.sub.4 hydrocarbons containing it and remarkable amounts of butadiene, and methyl tert-butyl ether is prepared, by feeding that stream of hydrocarbons and methanol to a reactor containing a catalyst consisting of an acid ion-exchange resin, maintained at a temperature in the range of from 60.degree. to 120.degree. C, at a space velocity (LHSV) in the range of from 5 to 35, the relation between the space velocity (LHSV) and temperature being correlated to correspond to the formula: LHSV = 1/2t - 25, wherein t is the temperature in degrees C, so that the isobutylene and methanol are caused to react, and then separating the methyl tert-butyl ether thus formed from the reaction mixture by distillation.

Abstract: Methyl tert-butyl ether is prepared, and a stream of hydrocarbons containing isobutylene is freed therefrom, by reacting the isobutylene with methanol in a two stage process wherein, in the first stage, a stream of hydrocarbons containing isobutylene and methanol is fed to a primary reaction zone where the isobutylene and methanol partially react in the temperature range of from 50.degree. to 90.degree.C and at a pressure of from 10 to 30 atmospheres in the presence of a catalyst to form methyl tert-butyl ether which is separated by distillation from the residue of isobutylene and methanol and all other hydrocarbons in the feed stream, and, in a second stage, the residue of isobutylene and methanol and other hydrocarbons is fed to a secondary reaction zone where the residue of isobutylene and methanol react in the vapor phase, at a temperature in the range of 60.degree. to 100.degree.