Leaves - Sumac
Leaves - Sumac
Mechotech designs and manufactures turnkey natural colour extraction plants for sumac leaves. In the Mechotech catalogue, Leaves - Sumac is listed in the Grey to Black Colour group alongside Galls - Oak Galls, Hulls - Walnut, Roots - Iris and the black bean, black rice and black carrot / black currant pages. According to Mechotech’s article on grey-to-black colour extraction from sumac leaves, sumac leaf is one of the richest natural sources of gallotannins. The extract is only pale tan on its own, and grey to black develops when the tannins react with iron. The plant is configured around that tannin extract.
Mechotech’s Leaves - Sumac plant is configured around the sumac leaf tannin extract. It is built in SS 316L with integrated solvent recovery, automation and full documentation, and is delivered as a commissioned turnkey system. The article describes a simple hot-water extraction of the dried, ground leaf, followed by filtration, vacuum concentration and either sale as a liquid or spray drying to a tannin-dye powder standardised on tannin content, with the iron reaction that develops the grey-to-black carried out by the dyer or tanner. The line is configured for that route, or for food-grade alcohol / aqueous extraction where the client prefers it, and whether an iron step is part of the supply scope is confirmed with the client. Final parameters are established during process development and pilot validation.
Technical Specifications
| Product | Leaves - Sumac Extraction Plant |
|---|---|
| Raw Material | Sumac leaves (catalogue name: Leaves - Sumac) |
| Botanical Name | Rhus spp. (the sumac genus, per Mechotech’s sumac article); the species is not stated in the catalogue and is confirmed with the client |
| Plant Part / Feed Form | Leaves, harvested from cultivated or wild stands, dried and ground (per the article); exact form confirmed with the client |
| Colour Group | Grey to Black Colour (see the Grey to Black Colour page) |
| Colour-forming Components | Hydrolysable tannins, chiefly gallotannins that release gallic acid. The extract alone is pale tan to light brown; grey to black forms when the tannins react with iron to give dark iron-gallate complexes (per the article) |
| Process Category | Natural Colour Extraction Plants |
| Extract Type | Sumac leaf tannin extract (liquid concentrate or dried powder, per specification) |
| Extraction Method | Hot-water extraction in closed jacketed SS 316L vessels (article reference: typically 70 to 95 °C), or food-grade alcohol / aqueous solvent; the route and conditions are confirmed during process development |
| Standardisation Basis | Tannin content and colour value, with solids and cleanliness, blended to a declared tannin strength (per the article); the target figure is agreed with the client |
| Product-contact Material | SS 316L |
| Filtration System | Plate-and-frame filter press with cartridge polish filters |
| Concentration System | Falling-film / vacuum evaporator with solvent recovery where a solvent is used |
| Drying System | Spray or vacuum dryer, where a powder is required |
| Automation | PLC-based |
| Plant Capacity | Configured to requirement |
| Utility Requirements | Steam, chilled/cooling water, compressed air and power (project-specific) |
| Compliance | GMP hygienic design; full documentation for qualification |
| Final Product Form | Sumac leaf tannin extract for grey-to-black colour development (liquid concentrate or dried powder) |
Plant Capacities
| Plant Scale | Raw Material Throughput | Typical Use |
|---|---|---|
| Pilot | Configured to your feedstock and trial plan | Product development, parameter validation |
| Semi-Commercial | Configured between pilot and commercial scale | Scale-up trials, contract manufacturing |
| Commercial | Configured to raw-material supply and confirmed buyer volume | Commercial production |
Capacity is configured to raw-material supply, confirmed buyer volume and investment timeline; a pilot plant is recommended to validate parameters before scaling.
Manufacturing Process
Raw Material Preparation
Sumac leaves are authenticated, tested for moisture, dried where required and ground, because the article notes that dried and milled leaf releases its tannins most efficiently; the particle size is set during process development.
Extraction
The ground leaf is extracted in closed jacketed SS 316L vessels at controlled temperature over several cycles, with hot water (the article’s reference range is typically 70 to 95 °C, as the tannins are water-soluble and heat-stable) or food-grade alcohol / aqueous solvent. The route and conditions are set during process development.
Filtration
The tannin liquor is separated from the spent leaf and clarified through a plate-and-frame filter press followed by cartridge polish filters.
Concentration & Solvent Recovery
The liquor is concentrated under vacuum in a falling-film / vacuum evaporator, with solvent recovered through the condenser return system where a solvent is used.
Standardisation
The concentrate is assayed for tannin content and colour value and blended to the declared tannin strength, which the article gives as the way to manage batch variation in leaf quality.
Drying & Quality Control
The standardised extract is supplied as a liquid or spray- or vacuum-dried to a tannin powder, per specification, then released after assay, residual-solvent (where a solvent is used), heavy-metal, microbial and moisture testing. In the article’s route the grey-to-black is developed afterwards by the dyer or tanner with an iron mordant or after-bath.
Major Plant Equipment
- Raw material cleaning, authentication and moisture testing
- Leaf drying and grinding (size-reduction) system
- Closed jacketed SS 316L extraction vessels
- Solvent storage tanks
- Plate-and-frame filter press
- Cartridge polish filtration
- Falling-film / vacuum evaporator
- Solvent recovery unit and condensers
- Standardisation / blending vessel
- Spray or vacuum dryer
- CIP system
- Automation and instrumentation
Plant Output
Applications
- Natural grey and black dyeing of wool, silk, cotton and linen with an iron mordant (per the article)
- Vegetable-tanning agent supply for leather (per the article)
- Traditional black ink and writing and art materials, in the manner of iron-gall ink (per the article)
- Cosmetic and personal-care tannin ingredient supply (the article notes the astringent character of sumac tannins)
Key Features
SS 316L Construction
Electropolished SS 316L product-contact surfaces with CIP operation between batches.
Closed-Loop Solvent Recovery
Where a solvent route is used, integrated condenser-return recovery reuses solvent between batches and reduces solvent loss.
Standardised to Specification
In-process and batch-release assay are used to check the finished extract against the agreed target specification, such as tannin content and colour value.
Water-Based Tannin Extraction
The article describes a simple hot-water extraction of the high-tannin leaf, which can be run without an organic solvent; an alcohol / aqueous route remains an option where the client prefers it.
Scalable Batch Capacity
Plants are configured to requirement from pilot scale upward, with modular expansion.
Frequently Asked Questions
Does Mechotech supply the complete machinery for Leaves - Sumac?
What specification can the Leaves - Sumac plant achieve?
What production capacities are available for the Leaves - Sumac plant?
Which industries use the Leaves - Sumac plant?
Why do sumac leaves give grey and black rather than a strong colour on their own?
How is the depth of grey-to-black controlled with sumac?
Which plant part and species are processed in the Leaves - Sumac plant?
How does the Leaves - Sumac extraction process work?
How does this page differ from Leaves - Tea / Sumac and Berries - Sumac?
Where does this page sit in the grey to black colour range?
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