Decarbonisation Technology May 2022 Issue

Aroforming a full-range naphtha with ethylene from FCC dry gas shows a large net margin at $247/t of naphtha based on US Gulf Coast long-range prices. The naphtha is co-processed with 0.27t of ethylene, priced at its fuel gas value. Aroformate yield is 92% at 90.3 RON, and LPG/C 4 yield is 34%. To what extent ethylene is the co-feed, the yield economics are improved by $100/t of naphtha. For a refinery with a 50K BPD FCC, this added benefit is worth $10 million/year. The Methaforming catalyst and process were developed and operating parameters optimised in three pilot plants with over 7,000 hours of processing. A fourth pilot plant, started up in 2019, has a 9 litre, three-stage reactor and capacity of a 320 l/d (2 BPD). It has confirmed the yields from the 100ml pilot plant, which has been used for 300 pilot plant tests on 50 different naphthas. NGTS is in active discussions with several refiners. A major refiner has included a 480K tpa (11K BPD) Aroformer into its long-range plan for 2024 based on extensive pilot plant testing. This unit will process aromatics extraction raffinate and a benzene precursor stream that is bypassed around reforming. Thanks to the pilot plant work with this refinery, our product offering has been enhanced by the flexibility to replace alcohol with FCC dry gas. Many potential customers are interested in quick delivery, low-cost, skid-mounted units. Most of these customers are in regions where there is not yet a significant value in CO2 emissions reductions. Their economics are driven by the availability of low-cost naphtha,

ton

$/t

Feeds

Naphtha Ethylene Products

1.00 0.27

530 230

Aroformate*

0.92 0.19 0.15 0.50

730 387 447

LPG

C 4

CO 2 reduction

Net margin

247

* 90.3 RON; higher severity to 95 RON may be achieved with somewhat lower Aroformate yield

usually because the facilities are located far from refineries, and there is a local demand for gasoline. An international EPC and NGTS have completed the detailed mechanical design for two versions. The contractor will build these at a fixed price of $1.2 million for a 6K tpa unit and $2.8 million for a 21K tpa unit. These can be delivered within six and 18 months, and include all of the equipment necessary inside battery limit. The outside battery limit is dependent on existing customer facilities. Much of this may already be available or available on an incremental cost basis. These low-cost modular Methaformers may be of interest to Western refiners who have converted primarily to biodiesel, which produces only a small amount of naphtha. Additionally, a modular Methaformer may be used to upgrade raffinate from aromatics extraction. In both of these situations, Table 3 Yield economics for Aroforming naphtha with ethylene

H O H H C

Dehydration: releases 135 kj per kg (283 BTU per lb) of naphtha*

H O H

H Methanol

Water

Benzene

Toluene

H H H H H H H H

Dehydrogenation: absorbs 129 kj per kg (269 BTU per lb) of naphtha

Hydrogen

N-hexane

Cyclohexane

Benzene

Figure 3 Methaforming dehydration of methanol and dehydrogenation of hexane, assuming 28.3 wt% share of alcohol co-feed