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                                                                   EXHIBIT 10.20

                                                           [LETTERHEAD OF SIPEX]

February 2nd, 2003

Mr. Phil Kagel
313 Windchime Drive
Danville, CA 94506

Dear Phil:

It is a pleasure to extend an offer of employment to join Sipex Corporation in
the position of Senior Vice President of Finance and Chief Financial Officer
reporting to Walid Maghribi, President and CEO of Sipex Corporation. Your total
base compensation package would be $4326.92/wk. ($225,000.00 annualized). In
accordance with our compensation plan, your performance and salary will be
reviewed on an annual basis. We will recommend to the Board of Directors that
you be issued 225,000 stock options at the fair market value at the time of
issuance. These options will be issued in accordance with our Stock Option
Policy. This offer is contingent upon the successful completion of a
satisfactory background check.

         If your employment with the Company terminates other than voluntarily
or for Cause, and you sign and do not revoke a standard release of claims with
the Company, then you shall be entitled to (i) receive continuing payments of
sevcrance pay (less applicable withholding taxes) at a rate equal to your Base
Salary rate, as then in effect, for a period of six (6) months from the date of
such termination, to be paid periodically in accordance with the Company's
normal payroll policies; and (ii) 50% of any unvested shares of any option shall
immediately vest and become exercisable until the earlier of (i) the original
term of the option or (ii) twelve (12) months from the date of termination.

If your employment with the Company terminates voluntarily by you or for Cause
by the Company, then (i) all vesting of the Option will terminate immediately
and all payments of compensation by the Company to you hereunder will terminate
immediately (except as to amounts already earned), and (ii) you will only be
eligible for severance benefits in accordance with the Company's established
policies as then in effect.

Notwithstanding the foregoing, in the event your employment with the Company
terminates voluntarily by you or other than for Cause by the Company in
connection with a "Change of Control" (as defined herein) that occurs within one
(1) year of the Effective Date, you shall be entitled to (i) receive continuing
payments (less applicable withholding taxes) at a rate equal to your Base Salary
rate, as then in effect, for a period of six (6) months from the date of
termination, to be paid periodically in accordance with the Company's normal
payroll policies; and (ii) 25% of the shares subject to the Option shall vest
and become exercisable. In the event your employment with the Company terminates
voluntarily by you or other than for Cause by the Company in connection with a
Change of Control that occurs more than one (1) year after the Effective Date
but within three (3) years of the Effective Date, you shall be entitled to (i)
receive continuing payments (less applicable withholding taxes) at a rate equal
to your Base Salary rate, as then in effect, for a period of six (6) months from
the date of termination, to be paid periodically in accordance with the
Company's normal payroll policies; and (ii) 50% of any unvested shares of any
option shall vest and become exercisable until the earlier of (i) the original
term of the option or (ii) twelve (12) months from the date of termination. In
the event your employment with the Company terminates voluntarily by you or
other than for Cause by the Company in connection with a Change of Control that
occurs more than three (3) years from the Effective Date, 100% of the any shares
of any option shall vest and become exercisable until the earlier of (i) the
original term of the Option or (ii) twelve (12) months from the date of
termination.

Sipex Corporation - 22 Linnell Circle - Billerica, MA 01821 - TEL: 978.667.8700
                              - FAX: 978.667.8310

    233 South Hillview Drive - Milpitas, CA 95035 - TEL: 408.934.7500 - FAX:
                                  408.935.7600

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For purposes of this letter, "Cause" is defined as (i) an act of material
dishonesty made by you in connection with your responsibilities as an employee,
(ii) your conviction of, or plea of nolo contendere to, a felony, (iii) your
gross misconduct, or (iv) your continued substantial violation of your
employment duties after you have received a written demand for performance from
the Company which specifically sets forth the factual basis for the Company's
belief that you have not substantially performed your duties.

For purposes of this letter, "Change of Control" of the Company is defined as:
(i) any "person" (as such term is used in Sections 13(d) and 14(d) of the
Securities Exchange Act of 1934, as amended) is or becomes the "beneficial
owner" (as defined in Rule 13d-3 under said Act), directly or indirectly, of
securities of the Company representing sixty percent (60%) or more of the total
voting power represented by the Company's then outstanding voting securities; or
(ii) a change in the composition of the Board occurring within a two-year
period, as a result of which fewer than a majority of the directors are
Incumbent Directors. "Incumbent Directors" will mean director who either (A) are
directors of the Company as of the date hereof, or (B) are elected, or nominated
for election, to the Board with the affirmative votes of at least a majority of
the Incumbent Directors at the time of such election or nomination (but will not
include an individual whose election or nomination is in connection with an
actual or threatened proxy contest relating to the election of directors to the
Company); or (iii) the date of the consummation of a merger or consolidation of
the Company with any other corporation that has been approved by the
stockholders of the Company, other than a merger or consolidation which would
result in the voting securities of the Company outstanding immediately prior
thereto continuing to represent (either by remaining outstanding or by being
converted into voting securities of the surviving entity) more than sixty
percent (60%) of the total voting power represented by the voting securities of
the Company or such surviving entity outstanding immediately after such merger
or consolidation, or the stockholders of the Company approve a plan of complete
liquidation of the Company; or (iv) the date of the consummation of the sale or
disposition by the Company of all or substantially all the Company's assets.
Notwithstanding the foregoing, a "Change of Control" shall not include any
transaction or series of transactions involving the Company's issuance of any
equity or debt securities to third parties for capital raising purposes.

Employment at Sipex Corporation will provide you with the opportunity to
participate in the employee fringe benefit program which includes your choice of
a medical and dental insurance program, term life insurance, disability income,
a tax deferred investment program (401K), Employee Stock Purchase Plan and paid
holiday and vacation plans. A Benefits Choices booklet is enclosed which
summarizes your benefits. Complete details on the plans will be available when
you sign up for benefits on your first day. If I can provide you with further
information regarding the position or the fringe benefits, please feel free to
contact me.

We are confident of the valuable contribution you will make toward the future
success of Sipex Corporation and we look forward to your joining us as soon as
possible. Please sign, date and return the original of the enclosed letter
confirming your concurrence with the terms of our offer as outlined above, and
indicating your start date. This offer is effective for three days from the date
of this letter. On your first day of work, please bring with you evidence of
your U.S. citizenship or proof of your legal right to live and work in this
country. We are required by federal law to examine documentation of your
employment eligibility within three days after you begin work.

This letter is not an employment agreement and does not constitute a guarantee
or promise of employment, it being your and our agreement, that you shall, at
all times, remain an employee at will and that your employment may be terminated
at any time by either the Company or you.

This letter (a duplicate original is enclosed for your records) along with any
agreements relating to proprietary rights between you and Sipex Corporation sets
forth the terms of your employment with Sipex Corporation

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and supersedes any prior representations or agreements, whether written or oral.
This letter may not be modified or amended except by written agreement, signed
by you and Sipex Corporation.

Sincerely,

/s/ Walid Maghribi
Walid Maghribi

President and Chief Executive Officer

I understand and accept the terms of this employment offer.

/s/ Phil Kagel
-----------------------
Phil Kagel

Date: 2/2/03               Start date: 2/10/03

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