Soxhlet quotations go wrong when buyers provide only: “I need a Soxhlet extractor, please quote.”
A quote becomes accurate only when the supplier can size:
extraction chamber and loading method
reflux rate & cycle frequency targets
condenser duty and cooling utilities
solvent recovery and reuse strategy
safety scope (explosion-proof, inerting, interlocks)
downstream integration (filtration, concentration, drying)
If you’re new to the method, read this first: Soxhlet Extraction: Lab vs Industrial, How It Works & When to Use It
Copy/Paste RFQ Checklist (send to suppliers)
A) Material & product goals (must-have)
Material name and description
plant/botanical name (or solid sample type)
form: cut / powder / granule / resinous chunks
moisture level (dry / semi-dry / wet; % if known)
Target compounds
what you want to extract (e.g., oils, resins, phenolics, caffeine, etc.)
any compounds you want to avoid (chlorophyll, waxes, sugars)
Final product form
crude extract / concentrated paste / dry powder / purified fraction
quality requirements: color, odor, impurity limits, residual solvent targets
B) Solvent system & constraints (must-have)
Preferred solvent(s)
single solvent or blend (if known)
solvent restrictions: food grade / pharma / local regulatory limits
Solvent selection intent
goal is “exhaustive extraction” or “selective extraction”?
any previous experience (too green, too viscous, low yield)
Safety notes
flammable/toxic solvent? special storage restrictions?
can you use nitrogen blanketing if required?
Related reading (solvent selection):
Soxhlet Solvent Selection: Polarity, Boiling Point & Safety
C) Capacity & throughput (must-have)
Batch size target
kg of dry material per batch (or liters of packed volume)
Daily throughput target
kg/day or batches/day and operating hours/day
whether you run 5 days/week or 24/7
Scale type
lab / pilot / industrial production
if pilot: is it for process validation or long-term small production?
D) Performance targets (highly recommended)
Extraction endpoint criteria
time-based (hours) OR preferred: cycle-based / assay-based endpoint
do you have assay method (HPLC/GC/UV) for “plateau” confirmation?
Target reflux rate or cycle frequency (if known)
If you have lab data, provide:
reflux rate (mL/min or drops/sec)
average cycle time (min/cycle)
cycles/hour and total cycles
If you don’t have this yet, ask supplier to propose a target based on your material and solvent.
Related reading (cycle control):
How to Control Soxhlet Cycle Time: Reflux Rate, Siphon Frequency & Yield
E) Utilities available (must-have for accurate sizing)
Electrical supply
voltage / phase / frequency (e.g., 380V/50Hz, 220V/60Hz)
Cooling source for condenser
tap water / chilled water / recirculating chiller
available cooling water temperature range and flow capacity (if known)
Vacuum availability (if downstream concentration is needed)
do you have a vacuum pump or need it included?
Related reading (downstream concentration):
vacuum concentration for botanical extracts
F) Solvent recovery & reuse (must-have for industrial)
Do you need solvent recovery?
yes/no
target recovery % expectation (if you have a goal)
Recovered solvent quality requirements
reuse in same batch? reuse across products?
water content limits? contamination concerns?
Solvent storage & transfer preference
open transfer vs closed transfer
storage tank requirements (volume, material)
G) Safety scope (critical for pilot/industrial)
Installation environment
indoor/outdoor, ventilation quality, room size
hazardous area classification (if defined)
Explosion-proof scope requirement
required by your site or local regulations? (yes/no/unknown)
Safety interlocks and automation
cooling interlock, low level shutdown, high temp trip, alarms, data logging
manual / semi-auto / PLC recipe operation
Related reading (safety):
Soxhlet Safety: Solvent Handling, Explosion-Proof Design & Interlocks
H) Materials of construction & cleanliness
Preferred material
SS304 / SS316L / glass (lab)
seal material preference if known (PTFE, FKM, etc.)
Cleaning requirement
manual cleaning acceptable?
do you need CIP-like cleaning logic? (rare for Soxhlet, but possible in integrated skids)
I) Documentation & services (avoid misunderstandings)
Documentation required
datasheet + GA drawing
PFD / P&ID
electrical drawings
interlock list
manuals (O&M), spare parts list
Factory testing & acceptance
FAT (factory acceptance test) required?
what performance must be demonstrated (cycle stability, leak test, recovery rate)
Installation/commissioning
remote guidance or on-site?
operator training required?
“Minimum RFQ” Template (if you want a short email)
Copy/paste this if you want the shortest message that still gets an accurate quote:
Material: ____ (form, moisture, particle size)
Target compound(s): ____ ; avoid: ____
Solvent preference/restriction: ____
Batch size: ____ kg/batch; throughput: ____ kg/day
Endpoint: ____ (hours or cycles or assay target)
Utilities: power ____; cooling water/chiller ____
Need solvent recovery: yes/no; reuse requirement: ____
Safety scope: indoor/outdoor; explosion-proof requirement: ____
Documentation: ____ (GA/PFD/P&ID/FAT/etc.)
FAQ (with answers)
1. Why do you need particle size and moisture for a Soxhlet quote?
They affect bed resistance, swelling behavior, and cycle time stability—critical for sizing chamber volume, thimble media, and target reflux rate.
2. Why do you ask about reflux rate and cycle time?
Because Soxhlet performance is driven by reflux–siphon cycles, not just total hours. Cycle metrics help ensure repeatable yield.
3. Why is cooling utility information required?
Condenser sizing and stable reflux depend on coolant temperature and flow. Insufficient cooling is a major failure cause (vapor escape, solvent loss).
4. Can you quote without solvent recovery details?
Only roughly. Industrial economics and safety depend heavily on solvent recovery design and reuse strategy.
5. What is the most common missing item that causes long back-and-forth?
Throughput rhythm (batches/day), solvent restrictions, and safety scope (explosion-proof/interlocks).