Abstract: A process for recovering elemental sulfur from volcanic and non-volcanic ores is disclosed. Ore is processed by crushing the ore to a coarse particle size autoclaving to separate the sulfur from the ore, mild grinding to selectively reduce the size of the liberated sulfur particles, flotation and sulfur separation/filtration steps to produce a sulfur of at least 99% purity. The process recovers at least 90% of the elemental sulfur contained in the ore. The particular crushing of the ore and selective grinding techniques for reducing sulfur particles for reducing sulfur particles size are important factors in the efficiency of the process since the grinding techniques inhibit the formation of fine gangue which is difficult to separate from the liberated sulfur.

Abstract: An agglomerative heap leaching method for recovering gold, silver or other metals from low grade refractory ores. Hypochlorite compounds are incorporated directly into the ore agglomerates as they are formed. This provides ample time and opportunity for the hypochlorite to destroy, modify or passivate refractory components of the ore thereby improving metal recovery in the subsequent cyanide leaching step.

Abstract: Addition agents are blended with a modified tall oil pitch binder and briquetted, extruded, molded, pelletized, or tabletized into a unitary composition. This compacted composition is then fed into a metallurgical operation, such as steel-making, at an appropriate stage in the operation to effect a desirable composition or property. The tall oil pitch binder being modified chemically with either a polycarboxylic acid, a polyamine, a polyisocyanate, an epoxy resin or a polyol.