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                                                                   EXHIBIT 10.36

                                                                    [SIPEX LOGO]

March 26, 2004

Mr. Ray Wallin
15288 Peach Hill Road
Saratoga, CA 95070

Dear Ray:

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 $3846.15/wk. ($200,000 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 200,000 stock options at the fair market value at the time of
issuance (the "Option"). The Option will be issued in accordance with our Stock
Option Policy. This offer is contingent upon the successful completion of a
satisfactory background check.

In the event your employment with the Company terminates other than voluntarily
by you or by the Company other than for "Cause" (as defined herein) and provided
that you sign and do not revoke a standard release of claims with 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 shall be entitled to receive
continuing payments of severance 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 polices.

In the event you terminate your employment with the Company voluntarily or the
Company terminates your employment for "Cause," 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 not be eligible for any severance benefits
unless otherwise specifically agreed to by the Company.

For the 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.

Notwithstanding the foregoing, in the event your employment with the Company
terminates for "Good Reason" in connection with a "Change of Control" (as
defined herein) that occurs within two (2) years of the Effective Date or in the
event that the Company shall terminate your employment other than for Cause
during such period, 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 such
termination, to be paid periodically in accordance with the Company's normal
payroll polices; and (ii) 50% of the shares subject to the Option shall vest and
become exercisable. In the event your employment with the Company terminates for
"Good Reason" in connection with a "Change of

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Control" that occurs more than two (2) years after 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) 100% 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 For the purposes of this letter, "Good Reason" shall
mean any of the following without your written consent: (i) any material
diminution or material change in your position with the Company, (ii) a material
reduction by the Company in your base salary, (iii) a material reduction in the
aggregate program of employee benefits and perquisites to which you are
entitled, and (iv) a required relocation by more than 50 miles from Sipex
headquarter.

For the 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 13-d3 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 two-year period,
as a result of which fewer than a majority of the directors are Incumbent
Directors. "Incumbent Directors" will mean Directors 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 the 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 the 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 (40IK), 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.

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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 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
Sipex Corporation
President and Chief Executive Officer

I understand and accept the terms of this employment offer.

/s/ Ray Wallin                         Date:  3/31/04
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Ray Wallin

                                              4/5/04
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                                       Effective Start Date