A process includes reacting, in a reactor having a fixed bed containing a solid catalyst which contains a heterogeneous ion exchange resin, hydrogen sulfide and ethylene oxide in the presence of the solid catalyst to yield a reaction product which contains beta-mercaptoethanol. A reactor system includes the reactor, an ethylene oxide stream, a hydrogen sulfide stream, a fixed bed containing the solid catalyst placed in the reactor, and an effluent stream containing the reaction product. During steady state operation of the reactor in the process and the reactor system, the hydrogen sulfide and the ethylene oxide are present in a mole ratio in a range of about 9:1 to about 20:1.

A process includes reacting, in a reactor having a fixed bed containing a solid catalyst which contains a heterogeneous ion exchange resin, hydrogen sulfide and ethylene oxide in the presence of the solid catalyst to yield a reaction product which contains beta-mercaptoethanol. A reactor system includes the reactor, an ethylene oxide stream, a hydrogen sulfide stream, a fixed bed containing the solid catalyst placed in the reactor, and an effluent stream containing the reaction product. During steady state operation of the reactor in the process and the reactor system, the hydrogen sulfide and the ethylene oxide are present in a mole ratio in a range of about 9:1 to about 20:1.

A process includes reacting, in a reactor having a fixed bed containing a solid catalyst which contains a heterogeneous ion exchange resin, hydrogen sulfide and ethylene oxide in the presence of the solid catalyst to yield a reaction product which contains beta-mercaptoethanol. A reactor system includes the reactor, an ethylene oxide stream, a hydrogen sulfide stream, a fixed bed containing the solid catalyst placed in the reactor, and an effluent stream containing the reaction product. During steady state operation of the reactor in the process and the reactor system, the hydrogen sulfide and the ethylene oxide are present in a mole ratio in a range of about 9:1 to about 20:1.

Disclosed are methods which comprise the preparation of beta-lactones which provide for shorter reaction times with lower by-product formation. The method comprises contacting carbon monoxide with an epoxide in the presence of a carbonylation catalyst to form a reaction mixture under conditions such that the carbon monoxide distributed throughout the reaction mixture and the reaction mixture is substantially saturated with carbon monoxide. The reaction conditions and reactor designs are chosen to distribute the carbon monoxide throughout the reaction mixture and to maintain the reaction mixture as substantially saturated with carbon monoxide. Under these conditions the formation of beta-lactones over the formation of by-products is favored.