Abstract: Exhaust gas emissions from an internal combustion engine are controlled through the use of a heat exchanger, a sulfur oxide absorbent, and two catalytic converter zones. The exhaust gas is passed sequentially through: (1) a first catalytic converter zone, (2) the sulfur oxide absorbent, and (3) a second catalytic converter zone. The heat exchanger is used to transfer heat from the first catalytic converter zone to the second catalytic converter zone.

Abstract: Exhaust gas emissions from an internal combustion engine are controlled through the use of a heat exchanger, a sulfur oxide absorbent, and a catalytic converter. The exhaust gas is contacted with the sulfur oxide absorbent before it is passed to the catalytic converter, and the heat exchanger is used to extract heat from the exhaust gas before the exhaust gas is contacted with the sulfur oxide absorbent. The heat extracted from the exhaust gas by the heat exchanger is then used to heat the catalytic converter. In a preferred embodiment, the exhaust gas is also contacted with a hydrocarbon adsorbent which: (1) adsorbs organic compounds, such as hydrocarbons, from the exhaust gas at the low temperatures which are typical of an engine cold-start, and (2) desorbs them at the higher temperatures which are reached after sustained engine operation.

Abstract: A contact material composition containing an intimately mixed, mixed oxide of at least one cationic species of a naturally occurring Group IIIB element, at least one cationic species of a Group IIA metal of magnesium, calcium, strontium, and barium and a cationic species of aluminum, as well as methods for hydrocarbon conversion using such contact material compositions are provided.

Abstract: A contact material composition of an intimately mixed halogen-containing mixed oxide of at least one cationic species of a naturally occurring Group IIIB element, at least one cationic species of a Group IIA metal of magnesium, calcium, strontium and barium and at least one cationic species of germanium and gallium, as well as methods for hydrocarbon conversion using such contact material compositions are provided.

Abstract: A contact material composition containing an intimately mixed, mixed oxide of at least one cationic species of a naturally occurring Group IIIB element, at least one cationic species of a Group IIA metal of magnesium, calcium, strontium, and barium and at least one additional metal cationic species of zirconium and hafnium, as well as methods for hydrocarbon conversion using such contact material compositions are provided.

Abstract: A contact material composition of an intimately mixed halogencontaining mixed oxide of at least one cationic species of a naturally occurring Group IIIB element, at least one cationic species of a Group IIA metal of magnesium, calcium, strontium and barium and at least one cationic species of germanium and gallium, as well as methods for hydrocarbon conversion using such contact material compositions are provided.

Abstract: A contact material composition containing an intimately mixed, mixed oxide of at least one cationic species of a naturally occurring Group 111B elment, at least one cationic species of a Group IIA metal of magnesium, calcium, strontium, and barium and at least one additional metal cationic species of zirconium and hafnium, as well as methods for hydrocarbon conversion using such contact material compositions are provided.

Abstract: A contact material composition containing an intimately mixed, mixed oxide of at least one cationic species of a naturally occurring Group IIIB element, at least one cationic species of a Group IIA metal of magnesium, calcium, strontium, and barium and a cationic species of aluminum, as well as methods for hydrocarbon conversion using such contact material compositions are provided.

Abstract: An oxidative coupling catalyst composition for converting methane to a higher hydrocarbon comprising a mixed oxide of: a) a Group IIIB metal selected from the group consisting of yttrium, scandium and lanthanum; b) a Group IIA metal selected from the group consisting of barium, calcium and strontium; and c) a Group IVA metal selected from the group consisting of tin, lead and germanium and wherein the cationic species are present in the approximate ratio of 1:0.5-3:2-4, respectively, and an improved process employing same.