C4 Hydrocarbon Fuel Additive Production via Selective Hydrogenation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The conversion of crude hydrocarbon streams to fuel additives is inefficient and costly, resulting in products with high impurities and low octane numbers, failing to meet market quality requirements.
Innovation Solution
A method involving passing a feed stream of C4 hydrocarbons through a cracker unit, followed by a methyl tertiary butyl ether unit with methanol, then a selective butadiene hydrogenation unit, and finally a hydration unit, where the molar ratio of isobutylene to methanol and temperature and pressure conditions optimize the production of fuel additives like 1-butanol, 2-butanol, and tert-butyl alcohol with high octane numbers and low impurities.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If crude hydrocarbon streams are converted to fuel additives through conventional processes, then fuel additive products are produced, but the products have high impurities and low octane numbers, failing to meet market quality requirements
Solution Approach 1:
The conversion process is divided into multiple sequential unit operations: cracker unit, MTBE unit, selective hydrogenation unit, and hydration unit. Each unit performs a specific function to progressively purify and transform the crude hydrocarbon stream, with intermediate separation and purification steps that remove impurities at different stages, ultimately producing high-quality fuel additives with low impurities and high octane numbers
Solution Approach 2:
The crude hydrocarbon stream undergoes preliminary cracking and purification operations before the main conversion to fuel additives. The cracker unit pre-processes the feed stream to break down complex hydrocarbons, and the selective hydrogenation unit removes unwanted components like butadiene before the hydration reaction, ensuring that only suitable feedstocks enter the final conversion step
2Productivity
If conventional conversion processes are used, then fuel additives are produced, but the process is inefficient and costly
Solution Approach 1:
The process recovers and recycles valuable components from intermediate streams. The hydrogenation unit recovers hydrogen for reuse, and the selective removal of butadiene and other unwanted components allows for targeted conversion of desirable hydrocarbons to fuel additives, improving overall process efficiency and reducing waste
Solution Approach 2:
The process utilizes controlled changes in temperature, pressure, and catalyst composition across different units to optimize conversion efficiency at each stage. The hydration unit operates under specific conditions (temperature, pressure, catalyst type) that maximize the conversion of purified hydrocarbons to fuel additives while minimizing energy consumption and byproduct formation
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This method significantly improves the efficiency and quality of fuel additives, achieving high octane numbers and low Reid vapor pressures, thereby increasing their market value and reducing capital costs.
Implementation Method 1
a feed stream comprising C4 hydrocarbons through a cracker unit producing a cracked stream
Implementation Method 2
passing the cracked stream and methanol through a methyl tertiary butyl ether unit to produce a first process stream
Implementation Method 3
passing the first process stream through a selective butadiene hydrogenation unit to produce a second process stream
Implementation Method 4
passing the second process stream and water through a hydration unit producing a third process stream, wherein a temperature within the hydration unit is 30°C to 250°C, a pressure within the hydration unit is 500 kiloPascals to 20,000 kiloPascals
Data Source
AI summary
A method of producing a fuel additive includes passing a feed stream comprising C4 hydrocarbons through a methyl tertiary butyl ether unit producing a first process stream; passing the first process stream through a selective butadiene hydrogenation unit transforming greater than or equal to 90% by weight of the butadiene to 1-butene and 2-butene, preferably greater than or equal to 93%, preferably, greater than or equal to 94%, more preferably, greater than or equal to 95% producing a second process stream; passing the second process stream through a hydration unit producing a third process stream and the fuel additive; passing the third process stream through a total hydrogenation unit producing a hydrogenated stream; and passing the hydrogenated stream to a cracker unit.