TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The aqueous acidic stream comprises sulfuric acid and ammonium-rich stream comprises ammonium sulfate. Preferred Process: The method further involves contacting off-gas stream (160) with an aqueous alkaline stream (460) in a hydrogen sulfide-removal zone, to obtain off-gas stream (270) comprising carbon dioxide and hydrogen sulfide-comprising aqueous stream (260), passing the hydrogen sulfide-comprising aqueous stream through a flash vessel (350) to a bio-reactor (400) comprising sulfide-oxidizing bacteria in presence of oxygen, to generate sulfur slurry and regenerated aqueous alkaline, separating at least a portion of sulfur slurry from the sulfur slurry and regenerated aqueous alkaline stream (420), to obtain a sulfur slurry stream (470) and an aqueous alkaline stream, recycling the aqueous alkaline stream to hydrogen sulfide-removal zone, generating sulfuric acid stream from the sulfate in the sulfur slurry, passing the sulfuric acid stream to the ammonia scrubber as the aqueous acidic stream, passing condensed water stream comprising water, ammonia, carbon monoxide and hydrogen sulfide to sour water stripper, to obtain sour water stripper off-gas stream comprising ammonia, hydrogen sulfide and carbon dioxide and sour water stripper water stream and passing the sour water stripper off-gas stream to the off-gas stream (110). The slurry bleed stream is provided by further process which involves gasifying hydrocarbon feed in a gasification zone, to obtain a hot syngas stream comprising carbon monoxide, hydrogen, particulate solids, hydrogen cyanide, ammonia, hydrogen sulfide, carbon dioxide and optionally carbonyl sulfide or carbon disulfide, cooling the hot syngas stream in a cooling zone, to obtain a cooled syngas stream, separating the cooled syngas stream in a dry solid removal unit, to obtain fly ash and a wet solid syngas stream comprising carbon monoxide, hydrogen, particulate solids, water, hydrogen cyanide, ammonia, hydrogen sulfide, carbon dioxide and optionally carbonyl sulfide and/or carbon disulfide, separating the wet solid syngas stream in a wet scrubbing column, to obtain the slurry bleed stream and a raw syngas stream comprising carbon monoxide, hydrogen, hydrogen cyanide, ammonia, hydrogen sulfide, carbon dioxide and optionally carbonyl sulfide and/or carbon disulfide, passing the raw syngas stream to a high pressure hydrolysis unit to hydrolyze the hydrogen cyanide and carbonyl sulfide and/or carbon disulfide, to obtain a hydrolyzed syngas stream comprising carbon monoxide, hydrogen, ammonia, hydrogen sulfide and carbon disulfide and a condensed water stream comprising ammonia, carbon dioxide and hydrogen sulfide. Preferred Apparatus: The apparatus further comprises a hydrogen sulfide-removal zone to separate hydrogen sulfide from off-gas stream (160), where hydrogen sulfide-removal zone has primary inlet for off-gas stream (160) connected to the primary outlet of the low pressure hydrolysis unit, secondary inlet for an aqueous alkaline stream, a primary outlet for off-gas stream (270) comprising carbon dioxide and secondary outlet for hydrogen sulfide-comprising aqueous stream, bio-reactor to oxidize hydrogen sulfide in the hydrogen sulfide-comprising aqueous stream, where the bio-reactor comprises sulfide-oxidizing bacteria in presence of oxygen and has primary inlet for the hydrogen sulfide-comprising aqueous stream, which can be passed through flash vessel, primary outlet for sulfur slurry and regenerated aqueous alkaline stream and a primary solid/liquid separator (450) to separate the sulfur slurry from the regenerated aqueous alkaline, where the primary solid/liquid separator has primary inlet for the sulfur slurry and regenerated aqueous alkaline stream, connected to the primary outlet of the bio-reactor and primary outlet for sulfur slurry stream and secondary outlet for aqueous alkaline stream, sour water stripper to separate a condensed water stream comprising water, ammonia, carbon dioxide and hydrogen sulfide into a sour water stripper off-gas stream comprising ammonia, hydrogen sulfide carbon dioxide and sour water stripper water stream, where the sour water stripper has primary inlet for condensed water stream and primary outlet for sour water stripper off-gas stream, where primary outlet is in fluid communication with the primary inlet of the ammonia scrubber and the sour water stripper has secondary outlet for the sour water stripper stream.